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1455 | Vaccination | vaccination | page | publish | <!-- wp:html --> <div class="blog-info">This article was first published in July 2015; last revised in October 2022.<br><em>We thank Stephanie Shendale, Sarah Loving, Anita Milicic, and Andy Pollard for helpful comments and suggestions on earlier draft versions of this entry.</em></div> <!-- /wp:html --> <!-- wp:owid/summary --> <!-- wp:paragraph --> <p>Since the invention of the smallpox vaccine, vaccines have greatly reduced the prevalence of diseases everywhere in the world. This research article explains which vaccines are available and where they are, what their impact on global health is, and how the world can make more progress against early death and disease with the help of vaccines.</p> <!-- /wp:paragraph --> <!-- wp:list --> <ul><li><a href="#not-every-child-who-should-be-vaccinated-is-vaccinated">Vaccination coverage has improved greatly over the past decades, but globally 13.5 million children were not vaccinated in 2018</a></li><li><a href="#vaccines-save-lives">Vaccines are one of the most successful and cost-effective ways to prevent diseases</a></li><li><a href="#progress-made-with-vaccination">Increased vaccine coverage has led to decline of diseases</a></li><li><a href="#public-support-and-skepticism">9 out of 10 people in the world think that vaccinating children is important</a></li><li><a href="#coverage-impact-and-potential">The coverage for many vaccines is still too low and we are missing out on saving many more lives</a></li></ul> <!-- /wp:list --> <!-- /wp:owid/summary --> <!-- wp:heading {"level":4} --> <h4>Related writing</h4> <!-- /wp:heading --> <!-- wp:list --> <ul><li><a href="https://ourworldindata.org/smallpox">Smallpox</a> — How has vaccination eradicated smallpox?</li><li><a href="https://ourworldindata.org/eradication-of-diseases">Disease eradication</a> — How and which diseases can be eradicated?</li><li><a href="https://ourworldindata.org/pneumonia#pneumococcal-vaccines">Child & </a><a href="https://ourworldindata.org/child-mortality#">infant</a><a href="https://ourworldindata.org/pneumonia#pneumococcal-vaccines"> mortality</a> — What are children dying from and how can we prevent it?</li></ul> <!-- /wp:list --> <!-- wp:heading --> <h2>Not every child who should be vaccinated is vaccinated</h2> <!-- /wp:heading --> <!-- wp:heading {"level":4} --> <h4>Global vaccine coverage</h4> <!-- /wp:heading --> <!-- wp-block-tombstone 28385 --> <!-- wp:paragraph --> <p>This chart shows the global vaccination coverage of one-year-olds with some of the most important vaccines recommended by the WHO. For many essential vaccines coverage is now much higher than 80%. However, the rates of vaccination are still not sufficient. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>If you click the play button you see that the coverage for most vaccines has increased substantially over time.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The vaccine against diphtheria, tetanus and pertussis, is often used as the key metric for global vaccination coverage because it is a good indicator for access to routine immunization services. In 2018, coverage of the third dose of DTP was 86%. This means that out of 135 million under-one-year-olds more than 19 million did not receive full immunization. The coverage of the first dose of DTP was 90% indicating that <strong>13.5 million children were not vaccinated</strong> in 2018. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In 2018, only 35% of children globally received the rotavirus vaccine, which protects children from <a href="https://ourworldindata.org/diarrheal-diseases">diarrheal diseases</a> — <a href="https://ourworldindata.org/child-mortality#what-are-children-dying-from">one of the leading causes</a> of child mortality. Similarly, pneumococcal vaccine that protects children from <a href="https://ourworldindata.org/pneumonia">pneumonia</a> — the leading cause of child mortality — only reached 47% of one-year-olds.{ref}This and other numbers in this entry are based on the estimates by the World Health Organisation. The coverage estimates are calculated by dividing the total number of vaccinations given by the number of children in the target population. Target population size is usually based on census population projections.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>This means that there may be children in the target population that for medical reasons should be exempt from vaccination. These medical reasons may include factors such as allergies to vaccine components or severe immunodeficiencies. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Notably, such cases are very rare and would have little effect on global coverage numbers. For example, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4783279/">a study</a> from 2003 identified severe allergic reaction in only 0.000063% of all vaccinations, that's 0.63 cases per million vaccinations. In addition, vaccines are always being improved with fewer ingredients that may cause allergic reactions. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Vaccination of children with immunodeficiencies generally needs to be assessed by a specialist. Especially, for vaccine that are based on a live pathogens. For example, <a href="https://www.who.int/immunization/policy/Immunization_routine_table1.pdf">WHO recommends</a> vaccinating HIV-positive children with measles vaccine if child's HIV infection is asymptomatic or not severe. Similarly, children with severe immunodeficiency syndrome (SCID), a genetic disorder that causes defects in immune system, are <a href="https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/severe-combined-immunodeficiency-scid">safely vaccinated</a> with many vaccines before SCID is even diagnosed, but it's recommended not to vaccinate them with live vaccines. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In fact, one of the reasons it is important to increase vaccination rates is that those children and adults who for medical reasons cannot be vaccinated would still be protected from diseases through <a href="https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity">herd immunity</a>.{/ref} </p> <!-- /wp:paragraph --> <!-- wp:quote --> <blockquote class="wp-block-quote"><p><strong>Related chart - the <em>number</em> of children vaccinated</strong>. <a href="https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds?time=1980..2015">This chart</a> shows how many one-year-olds were vaccinated globally.</p></blockquote> <!-- /wp:quote --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/global-vaccination-coverage" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Prosperity and vaccination coverage</h4> <!-- /wp:heading --> <!-- wp-block-tombstone 28754 --> <!-- wp:paragraph --> <p>Why do not all children in the world receive vaccinations?</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>This chart shows that it is in poor countries where vaccination coverage is low. The vaccine coverage against diphtheria, pertussis (whooping cough), and tetanus is a good marker of the strength of a country’s immunization programs since several administrations are required. All rich countries have vaccination coverage rates of more than 90%. It is in low- and middle-income countries where coverage is low – in some countries below 50%.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But the chart also shows that some poor countries – like Burundi, Rwanda, and Bangladesh – achieve high coverage rates. Similarly, countries in which a large share of the population is living in extreme poverty often – but not always – have lower immunization rates, as <a href="https://ourworldindata.org/grapher/vaccination-coverage-dpt-by-extreme-poverty?endpointsOnly=0">this chart shows</a>.</p> <!-- /wp:paragraph --> <!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/vaccination-coverage-by-income-in" width="300" height="150"></iframe></figure> <!-- /wp:html --> <!-- wp:heading --> <h2>Vaccines save lives</h2> <!-- /wp:heading --> <!-- wp:paragraph --> <p>We know that vaccines save lives. But how many lives vaccines have they saved? </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The World Health Organisation (WHO) suggests that vaccination prevents 2-3 million deaths each year.{ref} <a href="https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage">https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage</a>{/ref} However, while we are certain that vaccines have saved millions of lives, calculating a precise number is impossible. Also the quoted number from the WHO is in important ways a very low estimate.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The counterfactual world, in which vaccines would have never been developed, would be so different that an estimate of the impact of vaccines is impossible. One example that makes this clear is to consider the impact of the smallpox vaccine: <a href="https://owid.cloud/smallpox">Smallpox</a> was once an extremely common and deadly infectious disease, but it has been eradicated globally back in 1977 thanks to the vaccination against the disease. It is impossible to know exactly how many people would die of smallpox today if scientists had not developed the vaccine. Reasonable estimates are in the range of around 5 million lives per year, which implies that between 1980 and 2018 around 150 to 200 million lives have been saved.{ref}UNICEF (1996) and Hinman, A. R. (1998) estimate that in the absence of a vaccine the world would have seen 5 million deaths due to smallpox every year in the mid-1990s.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Assuming that the estimate for the mid-1990s provides a midpoint estimate for the period since 1980 and therefore multiplying the 5 million per year estimate by the number of years between 1980 and 2018 means that since the eradication of the disease 190 million people’s lives were saved.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>UNICEF (1996) – Vaccines bring 7 diseases under control. Online <a href="https://www.unicef.org/pon96/hevaccin.htm">here</a>.{/ref} This makes clear why it is so difficult to estimate the number of lives saved every year and why the WHO estimate is rather low.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>How vaccines work & herd immunity</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 28395 --> <!-- wp:paragraph --> <p>The basic mechanism by which vaccines work is simple: Vaccines create immunity in an individual by introducing a weakened or killed form of the pathogen that make us ill – such as bacteria or viruses – or its toxins or one of its surface proteins. The vaccine induces acquired immunity so that when your body encounters the real disease-causing agent it is ready to mount a defense.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There is a collective social benefit in a high vaccination coverage. For most diseases, the greater the proportion of people who are immunized, the better protected is everyone in the population as the disease transmission can be reduced or stopped. Herd immunity is a community protection that is created when a high percentage of the population is vaccinated, such that it less likely that the infectious disease spreads.{ref}See Oxford's Vaccine Knowledge Project for an explanation here: <a href="http://vk.ovg.ox.ac.uk/herd-immunity">http://vk.ovg.ox.ac.uk/herd-immunity</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Herd immunity provides a protective barrier, especially also for those who <em>cannot</em> be vaccinated. These include vulnerable groups such as babies too young to be vaccinated or immune-compromised children who are the first potential victims of low vaccination rates.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>When a person is immune to a disease they can act as a barrier to slow down or prevent the transmission of disease to other people. When the number of people in a population that are immune against a disease is reached, such that a disease no longer persists in the population, this is called the <em>herd immunity threshold</em> (HIT). The table shows the HIT for several diseases. Measles and pertussis are highly contagious airborne diseases and a larger share of people need to be vaccinated to stop the transmission. Because of this these diseases have the highest HIT rates that need to be reached. For example, two doses of measles vaccination offers 99% protection, while in the absence of immunization, the lifetime risk of infection is nearly 100%.{ref}Beutels P, Van Damme P, Van Casteren V, Gay NJ, De Schrijver K, Meheus A. <em>The difficult quest for data on "vanishing</em>"<em>vaccine-preventable infections in Europe: the case of measles in Flanders</em> (<em>Belgium</em>). Vaccine. 2002 Oct 4;20(29-<br>30):3551-9 <a href="https://www.ncbi.nlm.nih.gov/pubmed/12297401">here</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":6} --> <h6>Herd Immunity Thresholds of vaccine-preventable diseases{ref}This table is taken from <a href="https://en.wikipedia.org/wiki/Herd_immunity">Wikipedia's entry on Herd Immunity</a> – the original sources are listed there.{/ref}</h6> <!-- /wp:heading --> <!-- wp:shortcode --> <table><thead><tr><th scope="col" colSpan="1">Disease</th><th scope="col" colSpan="1">Transmission</th><th scope="col" colSpan="1">Basic reproduction number</th><th scope="col" colSpan="1">Herd Immunity Threshold</th></tr></thead><tbody><tr><td colSpan="1" rowspan="1">Measles</td><td colSpan="1" rowspan="1">Airborne</td><td colSpan="1" rowspan="1">12–18</td><td colSpan="1" rowspan="1">92–95%</td></tr><tr><td colSpan="1" rowspan="1">Pertussis</td><td colSpan="1" rowspan="1">Airborne droplet</td><td colSpan="1" rowspan="1">12–17</td><td colSpan="1" rowspan="1">92–94%</td></tr><tr><td colSpan="1" rowspan="1">Diphtheria</td><td colSpan="1" rowspan="1">Saliva</td><td colSpan="1" rowspan="1">6–7</td><td colSpan="1" rowspan="1">83–86%</td></tr><tr><td colSpan="1" rowspan="1">Rubella</td><td colSpan="1" rowspan="1">Airborne droplet</td><td colSpan="1" rowspan="1">6–7</td><td colSpan="1" rowspan="1">83–86%</td></tr><tr><td colSpan="1" rowspan="1">Smallpox</td><td colSpan="1" rowspan="1">Airborne droplet</td><td colSpan="1" rowspan="1">5–7</td><td colSpan="1" rowspan="1">80–86%</td></tr><tr><td colSpan="1" rowspan="1">Polio</td><td colSpan="1" rowspan="1">Fecal-oral route</td><td colSpan="1" rowspan="1">5–7</td><td colSpan="1" rowspan="1">80–86%</td></tr><tr><td colSpan="1" rowspan="1">Mumps</td><td colSpan="1" rowspan="1">Airborne droplet</td><td colSpan="1" rowspan="1">4–7</td><td colSpan="1" rowspan="1">75–86%</td></tr><tr><td colSpan="1" rowspan="1">SARS</td><td colSpan="1" rowspan="1">Airborne droplet</td><td colSpan="1" rowspan="1">2–5</td><td colSpan="1" rowspan="1">50–80%</td></tr><tr><td colSpan="1" rowspan="1">Ebola</td><td colSpan="1" rowspan="1">Bodily fluids</td><td colSpan="1" rowspan="1">1.5–2.5</td><td colSpan="1" rowspan="1">33–60%</td></tr><tr><td colSpan="1" rowspan="1">Influenza</td><td colSpan="1" rowspan="1">Airborne droplet</td><td colSpan="1" rowspan="1">1.5–1.8</td><td colSpan="1" rowspan="1">33–44%</td></tr></tbody></table> <!-- /wp:shortcode --> <!-- wp:heading --> <h2>Progress made with vaccination</h2> <!-- /wp:heading --> <!-- wp:paragraph --> <p>In total there are now at least 28 human diseases against which we have effective vaccines.{ref}Cholera, Dengue fever, Diphtheria, Haemophilus influenzae type b, Hepatitis A, Hepatitis B, Hepatitis E, Human papilloma-virus, Influenza, Japanese encephalitis, Malaria, Measles, Meningococcal disease, Mumps, Pneumococcal disease, Pertussis, Poliomyelitis, Rabies, Rotavirus gastroenteritis, Rubella, Tetanus, Tick-borne encephalitis, Tuberculosis, Typhoid fever, Varicella, Yellow fever, Shingles (Herpes Zoster), and Smallpox.<br>See <a href="https://en.wikipedia.org/wiki/Vaccine-preventable_diseases">https://en.wikipedia.org/wiki/Vaccine-preventable_diseases</a> and <a href="https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/">https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/</a>{/ref} The breakthrough that allowed us to get there was made in the late 18th century, the smallpox vaccine was the very first vaccine.</p> <!-- /wp:paragraph --> <!-- wp-block-tombstone 28389 --> <!-- wp:heading {"level":3} --> <h3>Smallpox and the origin of vaccination</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Vaccination has a long history. An early form of vaccination was referred to as 'variolation' or more broadly as 'inoculation'. Practised for a long time in Asia, this was an ancient technique of deliberate <a href="https://owid.cloud/smallpox">smallpox</a> infection in which dried smallpox scabs were blown up the nose to infect the person with a form of the disease which was often milder. By the 1700s variolation had spread to Africa, India and the Ottoman Empire, followed by the UK and America, where the method of infection more frequently used was a puncture to the skin.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Variolation did work, but there were large risks. Those variolated could contract the more severe form of smallpox and die, and they could also transmit the disease to others.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In 1796 English physician Edward Jenner demonstrated another method of inoculation in which he relied on cowpox. Cowpox is a similar disease to smallpox and it had previously been observed that an infection with cowpox can protect against smallpox. Jenner conducted an experiment using matter from a cowpox lesion to inoculate his gardener’s eight-year-old son James Phipps. Two months later Jenner exposed the boy to smallpox lesion matter and when Phipps did not develop smallpox he concluded that he was protected against the disease. Jenner called the procedure ‘vaccination’ after 'vacca' the Latin word for cow because of the origin of this first vaccination from the cowpox virus.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Following the findings of Jenner as the first scientific attempt to control disease by vaccination, the smallpox vaccine went through many iterations, with the newer vaccines produced by modern cell culture techniques (passing the virus through cell culture makes the vaccine safer). By the middle of the 20th century confidence grew that smallpox could be the first disease that humankind might be able to eradicate. In 1967 the WHO launched a <a href="http://www.who.int/csr/disease/smallpox/vaccines/en/">global eradication of smallpox program</a>. Mass vaccination of over 80% of a country's population ensued but people who were nomadic or lived in politically unstable regions posed particular problems. A number of innovations came in the development of foot-powered injector called the <a href="http://www.who.int/csr/disease/smallpox/vaccines/en/">“ped-o-jet” and then the bifurcated needle</a>, which was efficient and cost-effective to use.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In order to reach large sections of population, epidemiologist <a href="http://www.who.int/csr/disease/smallpox/vaccines/en/">William Foege</a> developed Eradication Escalation (E2) to contain smallpox outbreaks during October (the seasonal low point of smallpox transmission where prevention of just few cases could stop a smallpox chain transmission). <a href="http://www.who.int/csr/disease/smallpox/vaccines/en/">Other obstacles faced</a> included forcibly vaccinating an Indian religious leader to convince his followers to be vaccinated, negotiation of ceasefires for vaccine transport in war-torn Nigeria, vaccinating in concentric rings around an outbreak, and cash bounties to reward the reporting of smallpox cases. Finally in 1977 the last case of naturally contracted smallpox was reported in Somalia, in Ali Maow Maalin, and in 1980 the <a href="http://www.who.int/csr/disease/smallpox/vaccines/en/">WHO announced that smallpox had been eradicated</a>. We cover the history of smallpox, including the vaccination and eradication, in more detail in our entry on <a href="https://owid.cloud/smallpox">smallpox</a>.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>Vaccine innovation</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The chart here shows a timeline of innovation in the development of vaccines. Each bar begins in the year in which the pathogenic agent was first linked to the disease and the bar ends in the year in which a vaccination against that pathogen was licensed in the US.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>For some diseases there has been a relatively short timespan between when the infectious agent was linked to the disease and when a vaccine was developed. Before 2020 the quickest development was that for measles. The agent was linked to the disease in 1953 and the vaccine was licensed in the U.S. in 1963. In 2020 this record was broken when <a href="https://owid.cloud/covid-vaccinations" data-type="page" data-id="38102">several vaccines</a> were developed within just one year to fight the <a href="https://owid.cloud/coronavirus" data-type="page" data-id="30223">coronavirus pandemic</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><a href="https://ourworldindata.org/malaria/">Malaria</a> is proving harder as it has been over a century since the agent was linked to the disease. Alphonse Laveran discovered in 1880 that the Plasmodium parasite is the cause for malaria.{ref}See Francis EG Cox (2010) – History of the discovery of the malaria parasites and their vectors. In <em>Parasites and Vectors</em>. Online <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2825508/#!po=8.33333">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Early vaccines developed in the last several decades were insufficiently effective and until recently none of the scientific efforts led to a licensed vaccine. Recently there has been new hope for a malaria vaccine as we document in <a href="https://ourworldindata.org/malaria#a-vaccine-against-malaria">the relevant section in our entry on malaria</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Vaccine innovation has followed both scientific and political-economic developments:</p> <!-- /wp:paragraph --> <!-- wp:list --> <ul><li>Bacterial culture techniques which allowed the development of bacterial vaccines for diphtheria, tetanus, and pertussis in the early 1900s.</li><li>The first and second world wars prompted combined efforts by universities, governments, and private companies.</li><li>By the 1950s viral tissue culture techniques allowed the development of vaccines against <a href="https://owid.cloud/polio">polio</a>, measles, mumps, rubella, and varicella (chickenpox).</li><li>New technologies in molecular biology and advanced chemistry techniques have most recently led to vaccines against hepatitis B, influenza, and pneumococcus, which causes pneumonia and meningococus, which causes meningitis and septicaemia.</li></ul> <!-- /wp:list --> <!-- wp:image {"id":42922,"sizeSlug":"full","linkDestination":"none"} --> <figure class="wp-block-image size-full"><img src="https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart.png" alt="" class="wp-image-42922"/></figure> <!-- /wp:image --> <!-- wp:paragraph --> <p></p> <!-- /wp:paragraph --> <!-- wp-block-tombstone 28383 --> <!-- wp:heading {"level":3} --> <h3>Progress against vaccine-preventable diseases in the US</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The visualization here shows the reduction in cases and deaths from vaccine-preventable diseases in the United States after the introduction of each vaccine. This data was published by Roush and Murphy (2007){ref}Roush and Murphy (2007) – Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155–2163. <a href="https://www.ncbi.nlm.nih.gov/pubmed/18000199">here</a>{/ref} and the data can be viewed in a table <a href="https://ourworldindata.org/roush-and-murphy-2007-data/">here</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>For several diseases the US has achieved a 100% reduction of cases and deaths and for many other diseases the reduction is often very substantial as well.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":6} --> <h6>Reduction of cases and deaths of vaccine-preventable diseases in the United States after the introduction of the vaccine.{ref}These data are taken from the research paper Roush and Murphy (2007) – Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155–2163 <a href="https://www.ncbi.nlm.nih.gov/pubmed/18000199">here</a>.<br> The vaccines against the diseases up till ‘Tetanus’ were vaccines licensed or recommended before 1980. The vaccines against the last 5 diseases were only licensed or recommended between 1980 and 2005.{/ref}</h6> <!-- /wp:heading --> <!-- wp:image {"align":"center","id":35037,"sizeSlug":"full"} --> <div class="wp-block-image"><figure class="aligncenter size-full"><img src="https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths.png" alt="" class="wp-image-35037"/></figure></div> <!-- /wp:image --> <!-- wp:heading {"level":4} --> <h4>The development of the vaccine against measles and the history of measles in the US</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The introduction of a vaccine was not the only reason for progress against these diseases, as the visualization shows. The case-fatality rates of measles was falling in high income countries such as the US prior to the introduction of the vaccine in 1960 – this is best seen by switching from the linear to the logarithmic axis. Improved living conditions, nutrition, and medical advancements meant that contracting measles was less and less likely to be fatal.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The rate of cases however was virtually unchanged until after the measles vaccine was introduced – as our visualization shows.{ref}See also 'Graphical proof that vaccines work (with sources)' in <em>Medium</em> online <a href="https://medium.com/@visualvaccines/graphic-proof-that-vaccines-work-with-sources-61c199429c8c">here</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>To account for such long-term changes, Roush and Murphy (2007) report data from the period shortly before the introduction of the respective vaccine. <a href="https://www.ncbi.nlm.nih.gov/pubmed/18000199">here</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>A visualization showing the total number of cases and deaths can be seen <a href="https://ourworldindata.org/grapher/measles-cases-and-death">here</a>.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/measles-cases-and-death-rate" width="300" height="150"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Global decline in vaccine-preventable diseases</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">The WHO estimates that </span><a rel="noopener noreferrer" href="http://www.who.int/mediacentre/news/releases/2017/infants-worldwide-vaccinations/en/" target="_blank"><span style="font-weight: 400;">2 to 3 million deaths</span></a><span style="font-weight: 400;"> are prevented every year through immunization against diphtheria, tetanus, whooping cough, and measles.</span>{ref}In our graphics and visualizations we rely on the <em>Institute for Health Metrics</em> (IHME) ‘<a href="http://ghdx.healthdata.org/gbd-results-tool">Global Burden of Disease Study 2016</a>’ estimates of child death rates from individual VPDs (compared with other causes), TB death rates across countries, and death rates from individual VPDs; this dataset extends back to 1990 and therefore provides a longer-term perspective on these changes over time. However, lack of estimates from the IHME on the role of vaccination in the prevention of deaths means we rely on WHO data for the number of deaths prevented each year through vaccination and the total amount of deaths VPDs are responsible for.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The rates reported by the WHO and IHME are in a similar range but do differ slightly. WHO data on individual disease death rates can be found here: <a href="http://www.who.int/gho/mortality_burden_disease/en/" target="_blank" rel="noreferrer noopener">http://www.who.int/gho/mortality_burden_disease/en/</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">Nonetheless, the WHO also estimates that VPDs are still responsible for </span><a href="http://www.who.int/mediacentre/commentaries/vaccine-preventable-diseases/en/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400;">1.5 million deaths</span></a><span style="font-weight: 400;"> each year. </span></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">In the chart we see the global number of deaths of children younger than 5 years per year from 1990 to 2017. The number of deaths which are wholly or partially preventable by vaccines are shown in color.{ref}Note that, as discussed later in this post, the role of vaccines in prevention varies between these causes of death. Measles, for example, has the capacity to be eliminated through vaccination. Diarrheal deaths, in contrast, cannot be eliminated through vaccination alone; hygiene, water services, and nutrition must also be prioritised.{/ref} The chart shows that the reductions in child deaths over this 25-year period were primarily achieved by a reduction of the number of deaths from vaccine-preventable diseases: The decline in causes which are not vaccine preventable has been modest, while the number of child deaths caused by diseases for which vaccines are available declined from 5.1 million deaths in 1990 to 1.8 million deaths 27 years later.</span></p> <!-- /wp:paragraph --> <!-- wp:image {"align":"center","id":23891,"linkDestination":"custom"} --> <div class="wp-block-image"><figure class="aligncenter"><a href="https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019.png"><img src="https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019-715x550.png" alt="" class="wp-image-23891"/></a></figure></div> <!-- /wp:image --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">Two vaccines are responsible for saving millions each year: ‘DTP’ against diphtheria, tetanus, and pertussis (whooping cough) and ‘MMR’ against measles, mumps, and rubella.{ref}Some countries only give measles vaccines combined with rubella (MR) or with varicella in addition (MMRV).{/ref} Before the measles vaccine was introduced in 1963, measles caused a large number of deaths globally, estimated at </span><a href="http://www.who.int/mediacentre/factsheets/fs286/en/" target="_blank" rel="noopener noreferrer"><span style="font-weight: 400;">2.6 million each year</span></a><span style="font-weight: 400;">. Because about 86% of the </span><a href="http://www.who.int/mediacentre/factsheets/fs378/en/"><span style="font-weight: 400;">world population is immunized today,</span></a><span style="font-weight: 400;"> the number of people killed by measles have been cut dramatically to an estimated 95,000 deaths in 2017. Tetanus and pertussis were also previously much bigger killers, with pertussis affecting especially children younger than 5 years and tetanus striking newborns (</span><a href="http://www.who.int/immunization/diseases/tetanus/en/"><span style="font-weight: 400;">killing an estimated 787,000 newborns</span></a><span style="font-weight: 400;"> in 1988, compared with 49,000 in 2013</span><span style="font-weight: 400;">).</span></p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>The way ahead</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">However, the gains in global vaccination coverage have slowed down slightly in the last few years. The WHO estimates that </span><a href="http://www.who.int/mediacentre/factsheets/fs378/en/"><span style="font-weight: 400;">19.5 million infants</span></a><span style="font-weight: 400;"> worldwide are still at risk of VPDs because they miss out on basic vaccines.</span>{ref}Highlighted are 10 countries <a href="http://www.who.int/mediacentre/factsheets/fs378/en/">where approximately 60%</a> of these infants live in: Angola, Brazil, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan, and South Africa.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">In addition, all the recommended doses of a vaccine need to be received for it to be most effective. In the case of measles three vaccine doses are recommended. Even though an estimated </span><span style="font-weight: 400;">85% of children receive their first dose of the vaccine, <a href="http://www.who.int/mediacentre/factsheets/fs378/en/" target="_blank" rel="noopener noreferrer">this drops to 64%</a> for the second dose.</span> <span style="font-weight: 400;">Therefore, it is not only lack of vaccination that is a problem, but it is under-vaccination that leads to deaths from VPDs.</span></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">What then are the most deadly VPDs? Which diseases continue to kill the most people? </span></p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>The most deadly diseases</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p><b>Tuberculosis:</b><span style="font-weight: 400;"> Determining which are the most deadly VPDs requires acknowledging that some vaccinations are more effective than others. While most vaccines included in national routine schedules are highly effective, a better vaccine for tuberculosis (TB) is desperately needed. It is Sub-Saharan Africa and parts of Asia in particular that <a href="https://ourworldindata.org/grapher/tuberculosis-death-rates">are affected by TB</a>, as the world map shows.</span></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">The vaccine for TB – Bacillus Calmette–Guérin (BCG) – has been in use for nearly 100 years. It protects against severe forms of TB but is </span><a rel="noopener noreferrer" href="https://wellcome.ac.uk/news/world-immunisation-week-seven-vaccine-challenges" target="_blank"><span style="font-weight: 400;">not effective against pulmonary TB</span></a><span style="font-weight: 400;"> (in the lungs) and has variable effectiveness against TB in adults.</span>{ref}Zwerling A, Behr MA, Verma A, Brewer TF, Menzies D, Pai M. The BCG World Atlas: A Database of Global BCG Vaccination Policies and Practices. <em>PLoS Medicine</em>. 2011;8(3):e1001012. doi:10.1371/journal.pmed.1001012. Available <a href="http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001012">here</a>.{/ref}<sup>,</sup>{ref}For a detailed commentary on why we do not yet have an effective TB vaccine see: Davenne T, McShane H. Why don’t we have an effective tuberculosis vaccine yet?<em> Expert Review of Vaccines</em>. 2016;15(8):1009-1013. doi:10.1586/14760584.2016.1170599. Available <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4950406/">here.</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Furthermore, resistance of antibiotics used to treat TB is increasing, meaning some people can no longer be cured by drugs. The estimated number of people in 2016 with <a href="http://www.who.int/features/qa/79/en/"><span style="font-weight: 400;">multi-drug resistant TB was 490,000</span></a><span style="font-weight: 400;">. </span></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">The fact that there is not a fully effective vaccine and that antibiotic treatment is facing serious difficulties makes TB the most deadly VPD.</span></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><span style="font-weight: 400;">Meningococcal meningitis and hepatitis B are also deadly VPDs. </span></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><b>Meningococcal Meningitis: </b><span style="font-weight: 400;">Despite the introduction of <em>MenAfriVac</em> in 2010, an effective vaccine against the most common type of meningitis in that region, meningococcal meningitis killed almost 130,000 people in 2016. Many cases occur in the so-called ‘meningitis belt’ of sub-Saharan Africa, crossing from Senegal to Ethiopia. Not all the countries in the meningitis belt have implemented mass vaccination campaigns for <em>MenAfriVac</em> and also do not benefit from the expensive <em>MenACWY</em> vaccine introduced into richer countries to protect against other types of meningococcal meningitis.</span>{ref}An affordable <em>MenACWYX</em> vaccine is being developed to cover all the types of meningococcal disease (with the exception of meningitis B, which is available through a separate vaccine) and will also have the ability to be transported at higher temperatures. It is currently in phase 1 clinical trial, with the hope that it will be available for use in 2020–2022.{/ref}<sup>,</sup>{ref}See Meningococcal disease in the Middle East and Africa: Findings and updates from the Global Meningococcal Initiative, Borrow, Ray et al. <em>Journal of Infection</em>, Volume 75 , Issue 1 , 1 - 11. Available <a href="http://www.journalofinfection.com/article/S0163-4453(17)30114-7/abstract">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><b>Hepatitis B:</b><span style="font-weight: 400;"> The vaccine against hepatitis B is also very effective (</span><a rel="noopener noreferrer" href="http://www.who.int/mediacentre/factsheets/fs141/en/" target="_blank"><span style="font-weight: 400;">an estimated 95% effectiveness</span></a><span style="font-weight: 400;"> in preventing disease), meaning increased vaccination could lead to a significant reduction in deaths. Still, global coverage of the hepatitis B vaccine is lagging. In 2015, while <a rel="noopener noreferrer" href="http://www.who.int/mediacentre/factsheets/fs141/en/" target="_blank">84% coverage was reached</a> for the third dose of the vaccine, the coverage for the birth dose was only 39%. Estimates from mathematical models have shown that if infant coverage would reach 90%, and the first dose administered at birth, 84% of global hepatitis B-related deaths could be prevented.</span>{ref}Susan T Goldstein, Fangjun Zhou, Stephen C Hadler, Beth P Bell, Eric E Mast, Harold S Margolis; A mathematical model to estimate global hepatitis B disease burden and vaccination impact, <em>International Journal of Epidemiology</em>, Volume 34, Issue 6, 1 December 2005, Pages 1329–1339, <a href="https://doi.org/10.1093/ije/dyi206">https://doi.org/10.1093/ije/dyi206</a>. Available <a href="https://www.ncbi.nlm.nih.gov/pubmed/16249217">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>Eradication of diseases through vaccination</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Eradication is the ultimate goal of vaccination against a disease.</p> <!-- /wp:paragraph --> <!-- wp:owid/prominent-link {"title":"How do we eradicate diseases?","linkUrl":"https://owid.cloud/eradication-of-diseases","mediaId":18598,"mediaUrl":"https://owid.cloud/app/uploads/2018/04/Costs-of-controlling-vs-eradicating-a-disease-1.png","mediaAlt":"","className":"is-style-thin"} --> <!-- wp:paragraph --> <p>One of the greatest successes that we can imagine for humanity is the complete eradication of a disease. For one human disease – smallpox – this has actually been achieved. The disease was fully eradicated in 1980. For other diseases we are getting close, as we show in our entry on the eradication of disease.</p> <!-- /wp:paragraph --> <!-- /wp:owid/prominent-link --> <!-- wp:heading {"level":4} --> <h4>On the way to the eradication of polio</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Polio is targeted for global eradication. This has become possible through the polio vaccine that was developed in 1955. The WHO estimates that in 2015, <a href="https://ourworldindata.org/polio/#polio-prevalence-in-the-developing-world-and-the-global-spread-of-the-polio-vaccine">85% of infants around the world</a> received three doses of polio vaccine. And the number of paralytic polio cases have <a href="https://ourworldindata.org/polio/#the-number-of-reported-polio-cases-by-world-region">decreased by over 99%</a> since the 1980s, from an estimated 350,000 to 400,000 paralytic cases per year to <a href="http://www.who.int/mediacentre/factsheets/fs114/en/">22 reported cases in 2017</a>.</p> <!-- /wp:paragraph --> <!-- wp:owid/prominent-link {"title":"Polio","linkUrl":"https://ourworldindata.org/polio/","mediaId":14021,"mediaUrl":"https://owid.cloud/app/uploads/2017/10/the-number-of-reported-polio-cases-by-world-region.png","mediaAlt":"","className":"is-style-thin"} --> <!-- wp:paragraph --> <p>We present the empirical evidence on the effort to eradicate poliomyelitis in an entry entirely dedicated to polio.</p> <!-- /wp:paragraph --> <!-- /wp:owid/prominent-link --> <!-- wp:heading {"level":4} --> <h4>Eradication of smallpox</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>While the benefits might possibly be forgotten as vaccine-preventable diseases have lost their threat thanks to the introduction of the vaccines it is still true that people around the world – including those in richer countries – continue to benefit from vaccinations.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>One of the greatest successes of global health is eradication of smallpox. Smallpox, which just decades ago killed several hundred thousand people every year was successfully eradicated in 1980 thanks to the global vaccination program.{ref}Smallpox is the only disease that affects humans which has been eradicated through vaccination. Rinderpest, a disease that affected cattle, has also been eradicated. Polio is getting close to being eradicated.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:owid/prominent-link {"title":"Smallpox","linkUrl":"https://owid.cloud/smallpox","mediaId":28152,"mediaUrl":"https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-scaled.png","mediaAlt":"","className":"is-style-thin"} --> <!-- wp:paragraph --> <p>You find more detail about the disease and its eradication in our entry on smallpox.</p> <!-- /wp:paragraph --> <!-- /wp:owid/prominent-link --> <!-- wp:heading --> <h2>Public support and skepticism</h2> <!-- /wp:heading --> <!-- wp-block-tombstone 28381 --> <!-- wp:heading {"level":3} --> <h3>People do not know how well we actually do in global vaccination</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Today vaccines protect millions of people around the world from infectious diseases. In this fight we are much, much further ahead than most people realize.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The first chart shows the evidence for this misperception. In this chart we plotted the survey responses that people gave when they were asked <em>“How many of the world’s 1-year old children today have been vaccinated against some disease?”</em>. The correct answer was 85.8%; this is the share of 1-year olds that received the third dose of the combination vaccine that protects against Diphtheria, Tetanus, and Pertussis (whooping cough).</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But in all countries in which people were surveyed people were much too pessimistic about the global coverage. Americans think that only 35% of the world's children are vaccinated, the true coverage is 50 percentage points higher.{ref}This survey result is in line with the finding of the <em>Gapminder Ignorance Project</em>, which studied Americans' perception of global vaccination efforts. Just as in the Ipsos Mori survey, the answers that most Americans gave were far off from the truth.</p> <!-- /wp:paragraph --> <!-- wp:image {"align":"center","id":15353,"linkDestination":"custom"} --> <div class="wp-block-image"><figure class="aligncenter"><a href="https://ourworldindata.org/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage.png"><img src="https://ourworldindata.org/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage-750x396.png" alt="" class="wp-image-15353"/></a></figure></div> <!-- /wp:image --> <!-- wp:paragraph --> <p>More information on the Gapminder 'Ignorance Test' can be found <a href="http://www.gapminder.org/ignorance/">here</a>. The results for the US are <a href="http://www.gapminder.org/news/ignorance-survey-in-the-usa-2013/">here on Gapminder's site</a>.<br> {/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In Japan people were even more pessimistic and thought that only 18% were vaccinated. As it is often the case in questions on global development we again see that people in poorer countries have a <a href="https://owid.cloud/wrong-about-the-world">more accurate view of the world</a>: in Kenya and Senegal people thought that vaccines reach around two thirds of all children in the world, but even these highest estimates are 20 percentage points too low.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":6} --> <h6>We hugely underestimate global vaccination coverage{ref}<br> The survey results are from Chris Jackson (2017) – Global Perceptions of Development Progress: ‘Perils of Perceptions’ Research’, published by Ipsos MORI, 18 September 2017. Online <a href="https://www.ipsos.com/en/global-perceptions-development-progress-perils-perceptions-research">here</a>.{/ref}</h6> <!-- /wp:heading --> <!-- wp:image {"align":"center","id":20057,"linkDestination":"custom"} --> <div class="wp-block-image"><figure class="aligncenter"><a href="https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage.png"><img src="https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage-404x550.png" alt="" class="wp-image-20057"/></a></figure></div> <!-- /wp:image --> <!-- wp:heading {"level":4} --> <h4>People’s view on vaccination coverage is outdated by more than three decades</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The chart here illustrates how outdated people's answers are. Most individuals think that the global vaccination coverage today is as low as it was in the 1980s or even earlier.{ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><strong>Terminology: <em>vaccination</em> and <em>immunization</em></strong></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There is a technical difference between vaccination and immunization, as the National Health Service (NHS) <a href="http://www.shb.scot.nhs.uk/board/publichealth/immunisation.asp">explains</a>: “Vaccination means having a vaccine – that is actually getting the injection, or nasal spray or oral vaccine. Immunization means both receiving a vaccine and then becoming immune to a disease”. The distinction is made because in a very small number of those who are vaccinated the vaccination will not ‘take’ and therefore that vaccinated person will not be immunized (i.e. will not be immune to the disease). However, as this refers to a very small number of people both terms are often used interchangeably across the academic literature and in media reporting and we follow this convention in this entry.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The World Health Organization recommends routine vaccinations to prevent illness, death and disability from diseases including diphtheria, pertussis (whooping cough), tetanus, polio, measles, and hepatitis B.{ref}For the WHO recommendations see <a href="http://www.who.int/ith/vaccines/en/">http://www.who.int/ith/vaccines/en/</a></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The Bacille Calmette-Guerin (BCG) vaccine for tuberculosis (TB) is recommended in countries where TB is common. BCG policies and practices have varied considerably across time and countries. The <a href="http://www.bcgatlas.org/">BCG World Atlas</a> is an online resource that tracks these changes comprehensively.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>We have created a <a href="https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds">chart</a> that shows the absolute number of one-year-olds who have received the vaccinations.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Where the biggest gap in vaccination lies is with all children being fully vaccinated and protected as much as possible from infectious diseases. Gavi, the Vaccine Alliance, has analysis that suggests only <a href="https://www.nature.com/articles/d41586-017-05923-8">7% of infants in the 73 poorest countries are fully immunized (that is, receiving all doses of all recommended vaccines)</a>.</p> <!-- /wp:paragraph --> <!-- wp-block-tombstone 26483 --> <!-- wp:heading {"level":3} --> <h3>How many people support vaccination across the world?</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The London-based research charity <em>The Wellcome Trust</em> published their <a href="https://wellcome.ac.uk/what-we-do/our-work/wellcome-global-monitor">Wellcome Global Monitor</a> in 2019 on attitudes to science and major health challenges. It is the world’s largest study of its kind, surveying over 140,000 people from over 140 countries. As part of the <em>Gallup World Poll</em>, the 30-question survey ran during 2018.{ref}It provides data on topics such as trust in science and scientists; trust in sources of information about health; public understanding of the word ‘science’; the intersection between religious teachings and science; and attitudes to vaccines. In this post, we focus on how attitudes to vaccination vary across the world.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The Wellcome Trust survey asked three core questions related to attitudes to vaccines: do people think that vaccines are important for children to have; do they think vaccines are safe; and do they believe vaccines are effective.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Most people in the world think vaccines are important for children to have</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>More than 9-in-10 people in the world (92%) think that vaccines are important for children to have.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>How support varies across the world is shown in the map. We see high support for vaccination across almost all countries. In most countries over 80% of respondents think child vaccination is important, in many countries it is over 90% who think so.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There is a visible North-South divide in attitudes: support is highest across South Asia at 98%; 97% in South America; 94% in Northern Africa; and 92% in Southern Africa. Support is still high, but lower across North America (87%); Western Europe (83%) and Eastern Europe (80%).</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Of those surveyed in Venezuela, Palestine, Ethiopia and Northern Cyprus thought vaccines were most important: 100% were in favour.{ref}This is a stark result for Venezuela in particular (although perhaps unsurprising) since the availability and coverage of child vaccination <a href="https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1">has fallen significantly</a> over the last few years.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/share-agrees-vaccines-are-important-wellcome"></iframe></figure> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Most people in the world think vaccines are safe, but mistrust is high in some countries</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Some parents may not agree for children to be vaccinated if they think vaccines are unsafe or could potentially cause side-effects which are worse than the benefits. How prevalent are these safety concerns?</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Globally, a small share of people disagree that vaccines are safe. Only 7% of respondents across the world said they “strongly disagree” or “somewhat disagree” with the statement ‘Vaccines are safe’.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In many countries these concerns are very low: in Bangladesh, for example, less than 1% disagree that vaccines are safe. In neighbouring India, only 2% disagree. We see this distribution across the world in the map.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Trust in vaccines is not high everywhere. There are some clear outliers. The French were most skeptical: 1-in-3 disagreed that vaccines were safe. Many in neighbouring Switzerland and Belgium were also very skeptical: more than 20% disagreed. Other countries with high mistrust of vaccine safety were Gabon (26%); Togo (25%); Russia (24%); Austria (21%), and Iceland (21%).</p> <!-- /wp:paragraph --> <!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/share-disagree-vaccines-are-safe-wellcome-trust"></iframe></figure> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Only 5% of respondents globally disagree that vaccines are effective but skepticism is much higher in some countries</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>In response to the statement ‘Vaccines are effective’, only 5% of respondents across all surveyed countries said they “strongly disagree” or “somewhat disagree”. The vast majority of people do not think of vaccines as ineffective.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But, as with the other surveyed questions, this varies significantly across countries. We see this in the map. In some countries, very few respondents disagreed: less than 1% in Bangladesh and Egypt; 2% in India and Ethiopia; and 3% in China, Germany and the UK.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Liberia is most skeptical with 28% disagreeing that vaccines are effective. But skepticism was also high in France (18%); Namibia (16%); Nigeria (16%); and Peru (15%).</p> <!-- /wp:paragraph --> <!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/share-disagrees-vaccines-are-effective"></iframe></figure> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>In some countries many people are undecided on vaccination</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The finding of the Wellcome Trust of mostly very positive attitudes towards vaccines – a health intervention that <a href="https://ourworldindata.org/vaccination#how-is-the-world-doing-in-its-fight-against-vaccine-preventable-diseases">saves millions of lives</a> and <a href="https://ourworldindata.org/smallpox">eradicated one of the worst diseases</a> humanity ever faced – is a very positive finding.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But there is a concerning finding which is hidden when we look only at agreement and disagreement to the questions in the Global Monitor.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Take Japan as one example. Only 66% of Japanese respondents thought vaccines were important for children to have – very low in comparison to other countries. But few disagreed that vaccines were safe (only 8%) and disagreed that they’re effective (only 3%). If few people thought they were unsafe and ineffective, why would support for vaccines be so low?</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Many Japanese respondents did not answer either way. 28% answered “neither agree nor disagree” to <a href="https://ourworldindata.org/grapher/share-neither-agrees-disagrees-vaccines-important">whether child vaccination is important</a>; 55% to the question regarding the <a href="https://ourworldindata.org/grapher/share-neither-agree-disagree-vaccines-are-safe">safety of vaccines</a>; and one-third were undecided on their effectiveness. It's difficult here, without further questions, to fully interpret the opinions of those in this undecided category: maybe they had no opinion; or they thought vaccines could be safe or effective in some cases, but not all; or some vaccines were safe but others were not. With this data, it's impossible to fully understand their reasoning.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>This stance was common across several other countries, as we see in the map.</p> <!-- /wp:paragraph --> <!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/share-neither-agrees-nor-disagrees-vaccines-effective"></iframe></figure> <!-- /wp:html --> <!-- wp:paragraph --> <p>While being undecided or divided is perhaps less concerning than denialism on the importance, safety and effectiveness of vaccination, it nonetheless suggests that many are unaware of the massive role vaccines have played in <a href="https://ourworldindata.org/vaccination#eradication-of-diseases-through-vaccination">eradicating diseases</a>, and <a href="https://ourworldindata.org/vaccination#diseases-preventable-through-vaccination">saving lives across the world</a>. The success story of vaccines is one we don’t tell often enough.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>It’s also true that people in the 'neither' group may be more likely to be convinced by arguments that are put forward by those who deny the safety, effectiveness and importance of vaccination.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In a <a href="http://ourworldindata.org/vaccine-skepticism"><strong>related post</strong></a> we take a look at why denialism around vaccination exists, and what is effective in addressing it.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>Does vaccine skepticism affect immunization coverage?</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 26495 --> <!-- wp:paragraph --> <p>The crucial question to ask when considering the importance of vaccine skepticism is: does it actually have an effect on behaviour? Does it really affect the share of children who are vaccinated?</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In the chart we see the comparison of vaccination rates – here as the share of children who were immunized against diphtheria, pertussis and tetanus (DTP) in 2015, the latest year available – to the share of respondents in a given country who disagreed that vaccines are safe.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>You can also <a href="https://ourworldindata.org/grapher/immunization-measles-vs-vaccine-safety">see this relationship</a> for measles vaccine coverage.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Overall we see that widespread public concern for vaccine safety does not appear to be strongly correlated with vaccination rates. While one-third of the French public disagrees with their safety, 97% of children in France are vaccinated.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There are numerous other reasons, however, why vaccination rates in some countries are low: in low-to-middle income countries the availability, affordability and access to vaccines can be poor. Having low coverage rates often doesn’t reflect the population’s view of them. As the chart shows, in many poor countries the situation is the opposite as in France: the vast majority of the population considers vaccine safe, but only about every second child receives the DTP vaccine.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>One country which stands out is Ukraine: there we see that vaccination rates are uncharacteristically low for <a href="https://ourworldindata.org/grapher/gdp-per-capita-worldbank">its income level</a> – less than 1-in-4 children receive the DTP vaccine. Skepticism of vaccine safety in Ukraine is high at 15%.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Is there evidence that skepticism is reflected in cases and deaths from vaccine-preventable diseases? Over the last few years there has been <a href="https://www.who.int/csr/don/06-may-2019-measles-euro/en/">a reported rise</a> in the number of measles cases in countries which had previously been close to eliminating the disease. In Europe, for example, there were more than <a href="https://www.who.int/csr/don/06-may-2019-measles-euro/en/">34,000 cases of measles</a> in the first two months of 2019 alone. Ukraine <a href="https://www.who.int/csr/don/06-may-2019-measles-euro/en/">accounted for the majority</a> (more than 70%) of these cases. And here as well as in Albania and Romania some measles cases led to the death of children.</p> <!-- /wp:paragraph --> <!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/perception-of-the-safety-of-vaccines-vs-vaccine-coverage"></iframe></figure> <!-- /wp:html --> <!-- wp:columns --> <div class="wp-block-columns"><!-- wp:column --> <div class="wp-block-column"><!-- wp:paragraph --> <p>The visualization shows the relationship between the share of people who trust doctors and nurses in their country and share who disagree that vaccines are safe. Overall we see that countries with higher levels of distrust in the safety of vaccines tend to also have less trust in health professionals.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There are however some outliers: France has relatively high trust in health staff, but are most mistrusting of vaccine safety.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Health officials are worried that skepticism of vaccination will begin to translate to lower vaccination rates. One reason being attributed to higher skepticism is the spread of misinformation on social media.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Social media firms do have a responsibility for dealing with misinformation and need to consider how to react carefully. Currently, social and online media companies are being asked by politicians in the US and UK to ban or control anti-vaccination messaging. Banning or strict control could reduce the exposure to such messages but does not solve the root problem: the public are asking questions about vaccines and are looking to find answers online. A worry is that banning certain sorts of information and groups will fuel suspicion and only drive activity elsewhere.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Nonetheless, demands on social media firms to act is increasing. A request for action by <a href="https://schiff.house.gov/news/press-releases/schiff-sends-letter-to-google-facebook-regarding-anti-vaccine-misinformation">Adam Schiff to the CEOs of Google and Facebook</a> sparked a cascade of responses. In an open letter, he asked for action against vaccine misinformation and similar demands have been made since, from the UK Health Secretary Matt Hancock among others.</p> <!-- /wp:paragraph --></div> <!-- /wp:column --> <!-- wp:column --> <div class="wp-block-column"><!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/trust-healthcare-vs-vaccine-safety"></iframe></figure> <!-- /wp:html --></div> <!-- /wp:column --></div> <!-- /wp:columns --> <!-- wp:paragraph --> <p></p> <!-- /wp:paragraph --> <!-- wp:heading --> <h2>Vaccine policy</h2> <!-- /wp:heading --> <!-- wp-block-tombstone 28400 --> <!-- wp:heading {"level":3} --> <h3>What determines if vaccinations are compulsory?</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Countries vary in whether vaccination is compulsory, mandatory (required according to specific mandates), or voluntary. Navin and Largent (2017) provide a helpful distinction between these policies. A compulsory policy is when refusing vaccination is illegal, while mandatory vaccination when certain goods and services are limited for not vaccinating.{ref}Navin M. Largent, improving non-medical exemption vaccine policies: three case studies. Public Health Ethics. 2017; 10: 225–234. Available <a href="https://philpapers.org/rec/NAVINV">here</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Which policy is followed has depended much on historical legacy, which becomes clear when one considers some of the different regulations and their history around the world:</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><em>Compulsory vaccination:</em> Many Eastern Bloc countries introduced compulsory vaccination during the communist era. Vaccination was previously compulsory in Romania for example and after a drop in vaccination rates the country is going through the process of reintroducing compulsory vaccination. The same is true for Italy and also France, which had compulsory vaccination for three diseases but increased this number to 11 in January 2018 in response to a drop in vaccination rates.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><em>Mandatory vaccination:</em> Some countries, such as the United States, have mandates for vaccination where a child is required to be vaccinated to enter state school or daycare. An early case in the US paved the way for state jurisdiction to protect public health in light of personal liberty.{ref}See: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/</a>{/ref} In Jacobson v. Massachusetts (1905) the Supreme Court ruled that states have the authority to require vaccination against smallpox during a smallpox epidemic. Since then the US has had a history of school vaccination requirements. The increased number of children in public schools as a result of the compulsory school attendance law led to an increased risk of smallpox outbreaks, through close contact in large crowded classrooms.{ref}Stern, M., Alexandra. (2010). Better Off in School: School Medical Inspection as a Public Health Strategy During the 1918-1919 Influenza Pandemic in the United States{/ref} Similarly in Australia two policies penalize parents for not vaccinating their children. The 'No jab no play' policy removed unvaccinated children from state-sponsored childcare. The 2016 'No jab no pay' policy removes state welfare by not providing the universal 'Family Allowance' welfare payments for parents who are conscientious objectors of vaccination.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><em>Voluntary vaccination:</em> Some countries where vaccination is voluntary had early pushback against vaccination, as in the UK and the Netherlands. In 1853 a law was passed in England and Wales requiring universal vaccination against smallpox, but opposition from anti-vaccinationists led to laws being passed to allow for conscientious objection.{ref}Amin, A.N.E., Parra, M.T., Kim-Farley, R. et al. (2012) – Ethical Issues Concerning Vaccination Requirements. In <em>Public Health Reviews</em> (2012) 34: 14. <a href="https://doi.org/10.1007/BF03391666">https://doi.org/10.1007/BF03391666</a>. Online here: <a href="https://link.springer.com/article/10.1007/BF03391666">https://link.springer.com/article/10.1007/BF03391666</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><em>Vaccination requirements for country entry:</em> For countries in Africa and South America where yellow fever is endemic or where the mosquito vector is present a certificate of proof of vaccination is required. Only then will the country issue a visa upon entry to that country to prevent importation of this disease (particularly if travellers come from, or have visited other yellow fever endemic areas).{ref}See: <a href="http://www.who.int/csr/ihr/icvp/en/index.html">http://www.who.int/csr/ihr/icvp/en/index.html</a>{/ref} In past centuries (17th to 19th), yellow fever was transported to North America and Europe, causing large outbreaks that disrupted economies and development, and in some cases decimated populations. Throughout the 18th and 19th century, yellow fever was among the most feared diseases in the ports of the Old and New World. Saudi Arabia is the only country that requires the <a href="http://www.who.int/ith/updates/20170408/en/">additional vaccinations of meningococcal disease and polio</a> for pilgrims visiting Mecca.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Does it work to make vaccinations compulsory?</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Whether compulsory vaccination results in improved vaccination rates is not a straightforward question to tackle because it is highly dependant on country context, historical circumstance, cultural and social norms, as well as the practicalities of implementing and enforcing such a law. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Certainly in <a href="https://theconversation.com/despite-scepticism-europe-has-high-vaccination-rates-but-it-shouldnt-be-complacent-75169">Eastern Bloc countries</a> when the vaccination law was compulsory, vaccination rates have been high but it is unclear whether to attribute this to the law or the behaviours and mechanisms of compliance under communist rule. Certain vaccinations have historically been compulsory such as smallpox, polio, and yellow fever. Here vaccination rates have also been high but it also encouraged organised opposition to vaccination and public discontent. This is a major concern for public health authorities that a relationship of trust, between governments and citizens is threatened (particularly for health where a rhetoric of self-responsibility, personalisation, and choice is encouraged). </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There are countries with high vaccination rates without compulsory vaccination and governments do not want to disrupt public trust and self-responsibility by making vaccination compulsory, particularly if it is not seen as needed. It has been argued that high coverage has been achieved through "other approaches or efforts" and so acceptance of compulsory vaccination might be problematic in countries such as Sweden, Norway, Denmark, the Netherlands, and the UK.{ref}Salmon, Daniel A et al., Compulsory vaccination and conscientious or philosophical exemptions: past, present, and future, The Lancet, Volume 367, Issue 9508, 436 - 442{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In recent years governments have acted in response to epidemics to make vaccinations compulsory, as we have seen for 2017-18 with compulsory vaccinations in France, Italy, Germany, and Romania.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>One country where we can see the effect of variation in vaccination policy is the US. In the US states decide what vaccine exemptions are permitted for children who receive education in schools or use daycare. Public schooling unfortunately means that schools are sites of epidemics for childhood diseases, which is the reason such vaccination laws are required.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In individual states exemptions are granted for medical reasons but many states also allow for philosophical, personal belief or religious exemptions. Only three states – Mississippi, West Virginia, and California – only allow for medical exemption. <a href="https://ourworldindata.org/app/uploads/2017/11/Screen-Shot-2017-11-10-at-15.31.35.png">Californian immunization rates have increased</a> following a new Senate Bill SB 277 in 2015 to remove non-medical exemptions to vaccination. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The chart here shows vaccination coverage and what exemptions are allowed for each state. Fewer exemptions generally mean higher vaccine coverage. Indeed, Mississippi does often top the list as having the highest vaccination rates because only medical exemptions are allowed in the state. But starkly, Mississippi residents are also consistently the <a href="http://www.businessinsider.de/unhealthiest-states-in-the-us-health-rankings-2017-12?r=US&IR=T">unhealthiest</a> and <a href="https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/">poorest</a> in the entire country. Health outcomes are very poor and many residents cannot afford healthcare (<a href="https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/">the state has the highest percentage without health insurance in 2017</a>). So perhaps it is unsurprising that residents accept subsidized vaccinations that are required for access to childcare and state schools.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":6} --> <h6>Vaccination coverage of children, by US state in 2016/17{ref}The data source for vaccination coverage: School Vaccination Assessment Report, 2016-17 school year.<br> Estimated vaccination coverage with 5 doses of Childhood Diphtheria toxoid, Tetanus toxoid, acellular Pertussis (DTaP) vaccination for kindergartners (typical age range is 4–6 years).<br><br>The data source for exemptions is: Immunization Action Coalition, "Exemptions Permitted for State Immunization Requirements," 2017; LexisNexis; StateNet 2017<br><br>Regarding the school vaccination coverage and exemption methods the source notes: "Each school year, school nurses, other school personnel, or health department personnel check the vaccination and exemption status of kindergartners enrolled in public and private schools as required by state law or regulation. State and local immunization programs measure vaccination coverage among children entering kindergarten annually. This may be done for every student or for a sample of students.<br><br>State and local areas set the vaccination requirements. Immunization information systems (IISs) may be used as one source of data for school vaccination assessment. The school-level data are reported to the health department. The aggregate data are reported to CDC for public and private schools. Data for home-schooled students are not routinely reported to CDC."<br><br>The types of permitted exemptions vary by state. For specific details refer to <a href="https://www.cdc.gov/vaccines/imz-managers/coverage/schoolvaxview/requirements/index.html">School Vaccination Requirements and Exemptions</a>.{/ref}</h6> <!-- /wp:heading --> <!-- wp:image {"align":"center","id":15521,"linkDestination":"custom"} --> <div class="wp-block-image"><figure class="aligncenter"><a href="https://ourworldindata.org/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1.png"><img src="https://ourworldindata.org/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1-521x550.png" alt="" class="wp-image-15521"/></a></figure></div> <!-- /wp:image --> <!-- wp:heading {"level":3} --> <h3>Vaccine supply</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 28393 --> <!-- wp:paragraph --> <p>Supply constraints have caused problems for country access to vaccination. One-third of 194 countries have run out of a vaccine for a month or longer – according to <a href="http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health">data</a> submitted to WHO and UNICEF – and this includes both high- and low-income countries. In the US, the Centers for Disease Control and Prevention (CDC) <a href="https://www.cdc.gov/vaccines/hcp/clinical-resources/shortages.html">stated</a> that reasons for shortages were multi-factoral and included "...companies leaving the vaccine market, manufacturing or production problems, and insufficient stockpiles". In 2018, it <a href="http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health">was reported</a> that shortages where supplies of vaccines were critically low included those that target yellow fever, hepatitis B, cholera, meningitis C, diphtheria, whooping cough, tetanus, hepatitis A, and tuberculosis.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Concerns about the supply of vaccines in an epidemic or pandemic have been raised. For example, the supply of yellow fever vaccine was limited for the outbreak in Angola in 2016 leading to the recommendation of a fractional dose to extend existing supplies.{ref}See the WHO <a href="http://www.who.int/emergencies/yellow-fever/mediacentre/qa/en/">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><a href="http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health">Laurie Garrett argues</a> that because the drug had become so cheap (60 cents for each vaccine 2008) few companies had an incentive to produce it and world stocks of the vaccine were nearing zero, forcing the WHO to dilute donated vaccines from countries like Brazil (which sent 18 million doses) by 5 to 1 with the hope they would still be sufficiently effective. Romania experienced a situation of parallel vaccine exports in 2016 where more vaccines were exported than was supplied to meet the country's needs. A shortage of the measles, mumps, and rubella (MMR) vaccine was partly responsible for the measles outbreak in 2016-17.{ref}See <a href="https://www.euractiv.com/section/health-consumers/news/romania-cuts-vaccine-exports-as-measles-outbreak-takes-hold/">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In Venezuela, a country experiencing an economic crisis, there are severe <a href="https://www.bbc.co.uk/news/resources/idt-sh/Venezuela_bridge">shortages of medicines, including vaccines</a>, which has led to an <a rel="noopener noreferrer" href="https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1" target="_blank">estimated one million</a> unvaccinated children and the re-emergence of diseases such as diphtheria and measles.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>The cost of vaccines</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>There are five big pharmaceutical companies{ref}According to MacKenzie, D. (2011) – Vaccines enjoy a healthy return. <em>New Scientist</em>. Available <a href="https://www.newscientist.com/article/dn20877-vaccines-enjoy-a-healthy-return/">online</a>.{/ref} that account for 80% of vaccine production: Sanofi Pasteur, GlaxoSmithKline, Merck, Pfizer, and Novartis.{ref}In 2014 their vaccine business was acquired by GlaxoSmithKline, as reported <a href="https://www.telegraph.co.uk/finance/newsbysector/pharmaceuticalsandchemicals/11444023/GSK-and-Novartis-complete-deals-to-reshape-both-drugmakers.html">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Many vaccines are only provided by one or two suppliers. For newer vaccines there are often particularly few suppliers due to the high investment needed to develop a vaccine.{ref}There are exceptions however. A vaccine for tetanus and diphtheria (td) for example, has a large number of suppliers (13, and 7 for the paediatric formulation).{/ref} As one would expect from competition, the WHO reports that when vaccines are produced by a greater number of suppliers it leads to a decline of the prices of those vaccines.{ref}Review of vaccine price data. Submitted by WHO European Region Member States through the WHO/UNICEF. Joint Reporting Form for 2013. Online <a href="http://www.euro.who.int/__data/assets/pdf_file/0009/284832/Review-vaccine-price-data.pdf?ua=1">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph {"className":"p2"} --> <p class="p2">In the past vaccines were often viewed as less profitable products for pharmaceutical companies, which led to a lack of investment and some companies pulling out of production altogether.{ref}The Economist. (2010). A smarter jab. Available <a href="http://www.economist.com/node/17258858#print">online</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But this has changed as the revenue of the global vaccines market has increased and richer country governments and insurance companies have been willing to pay more for new vaccines.</p> <!-- /wp:paragraph --> <!-- wp:paragraph {"className":"p2"} --> <p class="p2">In addition, growing economies such as India and China are investing more in vaccines as well as developing their domestic manufacturing capacity. Poorer countries now have Gavi to help governments pool resources and make advance purchase commitments.{ref}The Economist. (2010). A smarter jab. Available <a href="http://www.economist.com/node/17258858#print">online</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Gavi is an international organisation created in 2000 to bring together public and private sectors, with the goal of equal access to new and underused vaccines for children in poorer countries. It subsidizes vaccines that otherwise would not be affordable for low-income countries. In addition to subsidizing vaccines themselves, Gavi offers <a href="https://www.gavi.org/about/programme-policies/health-system-and-immunisation-strengthening-support-framework/">vaccine introduction grants</a>, which help to cover the costs of introduction of new vaccines into routine immunization schedules. The map here shows which countries are eligible for GAVI support. </p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/gavi-supported-countries" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:paragraph --> <p>Some vaccines still remain expensive. For example, the pertussis vaccine is available in two versions: whole cell (wP) containing the whole pertussis bacterium or acellular (aP) which contains a part of the pertussis bacterium. The pertussis vaccine is often combined with diphtheria and tetanus to produce either a DTwP or DTaP vaccine.{ref}See WHO guidance for more information at: <a href="https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf">https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <cite class="iUh30"><br></cite> <!-- /wp:html --> <!-- wp:paragraph --> <p>DTaP is slightly more expensive; it is sometimes called 'the painless vaccine' because it causes less of a local reaction and pain but should not be given to children over the age of seven. However, DTwP has been shown to be more efficacious at preventing the transmission and spread of disease to unvaccinated people and to those with weak immunity.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>New vaccines tend to be more expensive as they are under patent protection. For example when the HepB vaccine was developed many lower income countries could not afford to pay $30 per dose.{ref}Jaffe, A. B., Lerner, J., Stern, S., & National Bureau of Economic Research. Innovation Policy and the Economy Group. (2006). <em>Innovation policy and the economy</em>. MIT Press. <a href="https://books.google.co.uk/books/about/Innovation_Policy_and_the_Economy.html?id=9I7KowFvI9oC&source=kp_cover&redir_esc=y">here</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Today there is often a differentiation between the prices paid by countries as shown in the small table.</p> <!-- /wp:paragraph --> <!-- wp:html --> <h6>Price differences for vaccines between the US and developing countries{ref}The source of the data is the <a href="http://mshpriceguide.org/en/home/">International drug price indicator guide</a>{/ref}</h6> <!-- /wp:html --> <!-- wp:table --> <figure class="wp-block-table"><table class=""><tbody><tr><td><strong>Vaccine</strong></td><td><strong>Cost per dose in a developing country</strong></td><td><strong>Cost per dose in the US</strong></td></tr><tr><td>HepB</td><td>$0.58 - 13.20</td><td>$50 - 100</td></tr><tr><td>BCG</td><td>$0.16 - 1.11</td><td>$100 - 200</td></tr><tr><td>Yellow fever</td><td>$4.30 - 21.30</td><td>$50 - 100</td></tr></tbody></table></figure> <!-- /wp:table --> <!-- wp:heading {"level":3} --> <h3>Which countries include vaccines in their immunization schedules?</h3> <!-- /wp:heading --> <!-- wp:columns --> <div class="wp-block-columns"><!-- wp:column --> <div class="wp-block-column"><!-- wp:paragraph --> <p>Several vaccines, including rubella, mumps, and rotavirus, are included in immunization schedules in many countries around the world. This means these vaccines are provided and recommended through routine services.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>This doesn't necessarily tell us how many children <em>receive</em> these vaccines in each country. The vaccines may or may not be mandatory and their coverage rates may vary widely. Similarly, when countries do not have a vaccine in their schedule, this does not mean that the vaccine is completely unavailable in those countries, as it may be optional or available commercially.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In the chart you can see which countries include rubella vaccines in their national immunization schedules. Rubella vaccines became available for the first time in 1969, starting in the United States, where it was developed.{ref}Lanziera, T., Haber, P., Icenogle, J. P., & Patel, M. (n.d.). Rubella. In <em>Epidemiology and Prevention of Vaccine-Preventable Diseases</em>. Communication and Education Branch, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention.<a href="https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html"> https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html</a>{/ref} It was included in the schedules of the United States and most European countries as early as 1994 (the first year of this dataset). Over time, more countries included it in their schedule.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But this took many years for some countries: for example, it took until 2018 for it to be included in countries such as Uganda and Congo.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>As of 2021 some countries, such as Nigeria and South Africa, still do not include it in their schedules.{ref}World Health Organization. (2021). <em>New and underutilized vaccines introduction</em>.<a href="https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html"> https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In the links below, you can see these charts for other vaccines.</p> <!-- /wp:paragraph --></div> <!-- /wp:column --> <!-- wp:column --> <div class="wp-block-column"><!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/rubella-vaccine-immunization-schedule" loading="lazy" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --></div> <!-- /wp:column --></div> <!-- /wp:columns --> <!-- wp:columns --> <div class="wp-block-columns"><!-- wp:column --> <div class="wp-block-column"></div> <!-- /wp:column --> <!-- wp:column --> <div class="wp-block-column"><!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/haemophilus-influenzae-b-vaccine-immunization-schedule","className":"is-style-thin"} /--> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/hepatitis-b-vaccine-immunization-schedule","className":"is-style-thin"} /--> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/hepatitis-b-birth-dose-vaccine-immunization-schedule","className":"is-style-thin"} /--> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/human-papillomavirus-vaccine-immunization-schedule","className":"is-style-thin"} /--> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/inactivated-poliovirus-vaccine-immunization-schedule","className":"is-style-thin"} --> <!-- wp:paragraph --> <p></p> <!-- /wp:paragraph --> <!-- /wp:owid/prominent-link --> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/mcv2-vaccine-immunization-schedule","className":"is-style-thin"} /--> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/mumps-vaccine-immunization-schedule","className":"is-style-thin"} /--> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/pneumococcal-conjugate-vaccine-immunization-schedule","className":"is-style-thin"} /--> <!-- wp:owid/prominent-link {"linkUrl":"https://ourworldindata.org/grapher/rotavirus-vaccine-immunization-schedule","className":"is-style-thin"} /--></div> <!-- /wp:column --></div> <!-- /wp:columns --> <!-- wp:heading {"level":3} --> <h3>Why do vaccine schedules differ?</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 28391 --> <!-- wp:heading {"level":4} --> <h4>The chickenpox example</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Chickenpox (varicella) is an example of a vaccine that some countries adopt into their routine childhood vaccination schedules, while others do not. The question that follows is why there is a difference in opinion for introducing widespread uptake of a vaccine or not. Japan was one of the first countries to adopt universal chickenpox vaccination.{ref}Bonanni et al. 2009; Bonanni P., Breuer J., Gershon A., Gershon M., Hryniewicz W., Papaevangelou V., et al. (2009) – Varicella vaccination in Europe - taking the practical approach. BMC Med 7: 26 <a href="https://www.ncbi.nlm.nih.gov/pubmed/19476611">here</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Australia, Canada, Germany, Qatar, Republic of Korea, Saudi Arabia, Taiwan, Uruguay, U.S., Italy (Sicily only) and Spain (Madrid only) followed afterwards and adopted universal chickenpox vaccination. When extreme cases of chickenpox have occurred there have been calls for the vaccine to become <a href="http://www.bbc.co.uk/news/uk-england-cambridgeshire-36952432">available for free</a> through the National Health Service in the UK. However, most European countries do not vaccinate against chickenpox, except for 'at risk' groups. The main reason for not adopting universal vaccination is the high cost. Additional supporting justifications are that it is usually a <a href="http://www.nhs.uk/chq/Pages/1032.aspx?CategoryID=62">mild disease</a> and the benefit of fewer cases of shingles – as explained <a href="https://theconversation.com/everything-you-need-to-know-about-chickenpox-and-why-more-countries-dont-use-the-vaccine-63473">here</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The Centers for Disease Control and Prevention in the US ran the <a href="https://www.cdc.gov/chickenpox/surveillance/vasp.html">Varicella Active Surveillance Project</a> (VASP) from 1995 through to 2010 to monitor the impact of the varicella vaccination program and the key finding is shown in the chart. The coverage of the vaccine in Los Angeles County rose from 37.9% in 1997 to 95.1% in 2010, and in Philadelphia from 41.2% in 1997 to 94.6% in 2010 (one-dose vaccinations for children between 19 and 35 months of age). By 2010, varicella incidence declined by 98% in Antelope Valley (California) and West Philadelphia (Pennsylvania) compared with 1995. Outbreaks and hospitalizations also decreased rapidly. From 1995 to 1998, hospitalization rates ranged from 2.2 to 3.3 per 100,000 population but by 2006-2010 this had declined to 0.2 per 100,000 in Antelope Valley and 0.5 per 100,000 in Philadelphia.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Chickenpox is an example that can also help to answer the question of whether better hygiene or vaccination are in fact responsible for the reduced rates of disease. Although both are important, a more recently adopted vaccination such as chickenpox can demonstrate the effects of vaccination in reducing the rate of disease after the importance of hygiene was discovered and became a preventative measure against disease. As hygiene standards already reached high levels, the additional benefit of the vaccine is confirmed. The impact on disease rates demonstrate it is not hygiene but vaccination that reduced the incidence of chickenpox so dramatically in the US.</p> <!-- /wp:paragraph --> <!-- wp:image {"id":28812,"sizeSlug":"large"} --> <figure class="wp-block-image size-large"><img src="https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-786x550.png" alt="" class="wp-image-28812"/></figure> <!-- /wp:image --> <!-- wp:heading {"level":3} --> <h3>Which countries have mandatory childhood vaccination policies?</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 43443 --> <!-- wp:paragraph --> <p>With the widespread rollout of <a href="http://ourworldindata.org/covid-vaccinations">COVID-19 vaccines</a> globally, some countries have started to consider mandatory vaccination, although no country has yet to make vaccines mandatory for its population.{ref}Gostin, L. O., Salmon, D. A. and Larson, H. J. (2021) ‘Mandating COVID-19 Vaccines’, <em>JAMA</em>. American Medical Association, 325(6), p. 532. doi: 10.1001/jama.2020.26553.{/ref} While COVID-19 has resurfaced the debate on vaccination policies, it has been an important topic for many other diseases. The World Health Organization (WHO) estimates that vaccines save two to three million lives each year (excluding COVID). The development of vaccines against vaccine-preventable childhood diseases has been a key driver in the decline of <a href="http://ourworldindata.org/child-mortality">child mortality</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Despite it being such an important topic, it is surprising that information about which countries have mandatory vaccine policy is lacking, and it is childhood vaccines under a country’s national immunization schedules that are most commonly made mandatory.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In this article we present a new global dataset which looks at childhood vaccination policies across the world.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>How do childhood vaccination policies vary across the world?</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>We recently charted mandatory childhood vaccine policies worldwide as they are becoming an increasingly important policy intervention for governments trying to address low vaccination rates.{ref}Vanderslott, S., & Marks, T. (2021). <a href="https://www.sciencedirect.com/science/article/pii/S0264410X21005478">Charting mandatory vaccination policies worldwide</a>. <em>Vaccine</em>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The term ‘mandatory’ and ‘mandates’ are taken to mean quite different things across countries. Whilst the term is commonly used it is poorly defined.{ref}Attwell, K. and C. Navin, M. (2019) ‘Childhood Vaccination Mandates: Scope, Sanctions, Severity, Selectivity, and Salience’, <em>The Milbank Quarterly</em>, 97(4), pp. 978–1014. doi: 10.1111/1468-0009.12417.{/ref} Mandates require vaccination for a certain purpose, most commonly related to school entry for children. While definitional disagreements still persist, it remains important to better understand what policies are in place across countries and the reasons driving changes in policy over time.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Our list indicates whether a country has a mandatory vaccination policy for one or more vaccine and the strictness of the mandate on a scale ranging across three levels: mandatory, mandatory for school entry, or recommended. The childhood vaccines include the vaccines that protect from <a href="https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide">measles,</a> mumps, rubella, <a href="https://ourworldindata.org/grapher/immunization-coverage-against-diphtheria-tetanus-and-pertussis-dtp3-vs-gdp-per-capita">diphtheria, tetanus, pertussis</a>, <a href="https://ourworldindata.org/grapher/polio-rate-of-cases-vs-vaccination-coverage">polio</a>, rabies, hepatitis B, <a href="https://ourworldindata.org/rotavirus-vaccine">rotavirus</a>, <a href="https://ourworldindata.org/grapher/hib-vaccine">haemophilus influenzae type B</a>, and <a href="https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds?country=~OWID_WRL">tuberculosis</a> – some of which are administered as combined vaccines. We have classified a country as having a mandatory policy if they mandate for at least one vaccine. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The differences in vaccination policy across the world are shown in the map. By covering 149 countries we could identify some trends around where and why vaccines are mandatory today.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/mandatory-childhood-vaccination" loading="lazy" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:owid/help --> <!-- wp:heading {"level":4} --> <h4></h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p><em>Note: this is a live dataset that relies on crowdsourcing to note policy changes. If you are aware of any new policies or policy changes for any country please do get in touch at: [email protected].</em></p> <!-- /wp:paragraph --> <!-- /wp:owid/help --> <!-- wp:heading {"level":3} --> <h3>How do mandatory vaccination policies vary by region?</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>We found that assessing policies across WHO regions – European, Americas, Western Pacific, African, and Eastern Mediterranean – was a useful way to break down our analysis of policies worldwide.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In the chart you see a breakdown of the number of countries with a given policy mandate. You can view this by region by using the "Change region" toggle on the interactive chart.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Europe has a mixture of mandatory and recommended policies. But most European countries – 16 out of 28 – do not have mandatory vaccination. European countries were among the first to introduce mandatory vaccination for smallpox in the early 19<sup>th</sup> century, which also led to early push-back. The early introduction and early push-back, along with present-day approaches to foster mutual trust and responsibility between citizens and the health authorities, may be part of the reason why vaccination is often recommended rather than mandated in many European countries.{ref}Stuart Blume (2017) <em>Immunization: How Vaccines became Controversial - Stuart Blume - Google Books</em>. Reaktion Books.{/ref} Countries of the former-USSR (Union of Soviet Socialist Republics) or under the influence of the Eastern Bloc previously had mandatory vaccination, and many kept this policy in the post-USSR era.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Most countries in the Americas – 29 out of 35 – have mandatory vaccinations. In the USA, vaccination is regulated by individual states though it is mandatory for school entry in all of them. In Canada, only three provinces have legislated mandatory vaccination policies that apply to children enrolling in school.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In the Western Pacific region, changes to mandatory policies have gone in both directions. Some countries such as Singapore have moved towards mandatory vaccinations whilst others, such as South Korea transitioned away from mandatory to recommended vaccines in 1999. For other countries, mandatory policies are more ambiguous. In China, there is no evidence of specific legislation mandating vaccines, despite many references to such claims in the literature.{ref}Attwell, K., Drislane, S. and Leask, J. (2019) ‘Mandatory vaccination and no fault vaccine injury compensation schemes: An identification of country-level policies’, <em>Vaccine</em>. Elsevier Ltd, 37(21), pp. 2843–2848. doi: 10.1016/j.vaccine.2019.03.065.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>It was difficult to obtain information about vaccination policies across African countries, suggesting the absence of specific policies in the region. However, the policies we did find were for mandatory vaccination.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Most countries in the Eastern Mediterranean region have mandatory vaccines. Israel is an exception in only recommending vaccination, based on a vaccination schedule outlined by the National Immunization Technical Advisory Group.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There are a number of countries in South-East Asia with mandatory vaccination. India is similar to other large countries, with varying policies on mandatory vaccination at the state level. Finally, we note that there are some countries that have mandatory policies at a sub-country level such as in Canadian provinces and Indian and Australian states but we have classified these countries as to the national policy and the policies cover most of the country.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/number-countries-mandatory-vaccination?country=~OWID_WRL" loading="lazy" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>What drives the introduction of mandatory vaccinations?</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Overall, we found that the occurrence of recent outbreaks is a major factor in the introduction of mandatory vaccination, particularly for high and upper-middle-income countries in Europe. Germany, for example, made measles vaccination mandatory for school and day-care attendance in 2020 following large outbreaks.{ref}Rezza, G. (2019) ‘Mandatory vaccination for infants and children: the Italian experience’, <em>Pathogens and Global Health</em>. Taylor and Francis Ltd., pp. 291–296. doi: 10.1080/20477724.2019.1705021.{/ref} Similarly, Serbia tightened mandatory vaccination laws following a measles outbreak in 2014 to 2015 by introducing harsher penalties.{ref}Pejin LS. Tightening measures for compliance with vaccination in Serbia ESPN Flash Report. European Commission; 2016.{/ref} Trends of reported cases of measles can be explored in detail <a href="https://ourworldindata.org/grapher/reported-cases-of-measles?country=~DEU">here</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Secondly, many low- and lower-middle-income countries have resorted to mandatory vaccination policies because of a lack of other policy options. Nonetheless, many have still missed their target vaccination rates due to problems with vaccine supply, delivery, and access. In Guyana for example, vaccination is mandatory, yet vaccination coverage is hindered by the management of the supply chain in keeping storage temperatures consistent and the distribution of freeze-sensitive vaccines.{ref}UNICEF. Guyana Situation Analysis of Children and Women; 2016. Available at: <a rel="noreferrer noopener" href="https://www.unicef.org/sitan/" target="_blank">https://www.unicef.org/sitan/</a> [accessed: 10 April 2020].{/ref} In Nigeria, vaccination is mandatory, and several states have enacted legislation criminalising vaccine refusal. Yet as Onyemelukwe (2016) argues, there are structural, logistical, political, systemic, religious and cultural obstacles to the effective distribution and uptake of vaccines, ranging from cold chain issues, to corruption and security issues.{ref}Onyemelukwe, C. (2016) ‘Can legislation mandating vaccination solve the challenges of routine childhood immunisation in Nigeria?’, <em>Oxford University Commonwealth Law Journal</em>. Taylor and Francis Ltd., 16(1), pp. 100–124. doi: 10.1080/14729342.2016.1244450.{/ref} There is thus often variation between vaccination in policy compared to in practice.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>These findings will be useful to inform policymakers considering the merits of mandatory vaccination:</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>1) In the past, an outbreak of a disease (such as measles) has led to introduction of mandatory vaccines even in countries where previously all vaccinations were recommended;</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>2) Making a vaccine mandatory should not be the only policy tool but needs to be combined with strong access and availability of vaccines;</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>3) It is not just a matter of whether to mandate a vaccine, but how this mandate will be enforced, whether people will comply, and the impact on state-citizen relations. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In summary, mandatory vaccination must be considered with caution. A country’s past experience with mandates, vaccination services, ability for enforcement, public attitudes, and the current state of disease outbreaks will all play a part in whether mandatory vaccination should be introduced.</p> <!-- /wp:paragraph --> <!-- wp:heading --> <h2>Coverage, Impact, and Potential</h2> <!-- /wp:heading --> <!-- wp:heading {"level":3} --> <h3>Diseases preventable through vaccination</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The chart shows the number of global deaths caused by some of the most common and serious vaccine-preventable diseases.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>By selecting ‘change country’ it is possible to see this change for any country in the world and extending the timeline will let you see the change in deaths over time.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There are more diseases for which vaccines are available now and even more are under development currently. The WHO publishes list of <a href="http://www.who.int/immunization/diseases/en/">26 diseases</a> for which vaccines are available – including Japanese encephalitis, pneumococcal disease, varicella/chicken pox, HPV, Hepatitis A and rotavirus.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/Deaths-caused-by-vaccine-preventable-diseases-over-time" width="300" height="150"></iframe> <!-- /wp:html --> <!-- wp-block-tombstone 28387 --> <!-- wp:heading {"level":3} --> <h3>Diphtheria, Tetanus, and Pertussis vaccine</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Diphtheria, tetanus, and pertussis are all bacterial diseases and a combination vaccine against all three diseases is commonly used. </p> <!-- /wp:paragraph --> <!-- wp:list --> <ul><li>Diphtheria primarily infects the throat and upper airways and is fatal in 5 – 10% of cases.</li><li>Tetanus is not passed person-to-person but through spores of a bacteria living in soil and animal intestinal tracts. These bacteria enter the body through wounds and release a toxin that affects the nerves, which causes muscle stiffness and spasms.</li><li>Pertussis is a highly contagious disease of the respiratory tract, commonly known as whooping cough. Children who contract pertussis tend to have coughing spells that last four to eight weeks, but the highest fatality is in young infants. Vaccinating health workers and pregnant women is the most effective strategy for preventing disease in infants too young to be vaccinated. </li></ul> <!-- /wp:list --> <!-- wp:paragraph --> <p>The chart shows the progress over time of DTP3 immunization coverage of children around the world. By clicking on any country you can see the change in that country over time.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The WHO <a href="https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=OWID_WRL">reports</a> in 2017 that 85% of infants worldwide (116.5 million infants) received 3 doses of diphtheria-tetanus-pertussis vaccine (DTP3). Also in 2016 130 countries had reached at least 90% coverage with the DTP3 vaccine.{ref}See the WHO here: <a href="http://www.who.int/mediacentre/factsheets/fs378/en/">http://www.who.int/mediacentre/factsheets/fs378/en/</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>If we look at <a href="https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=East%20Asia%20%26%20Pacific+Europe%20%26%20Central%20Asia+Latin%20America%20%26%20Caribbean+Middle%20East%20%26%20North%20Africa+North%20America+South%20Asia+Sub-Saharan%20Africa">the change over time by world region</a> it is South Asia in particular that stands out. While 85% of one-year-olds today are immunized, that same figure was as low 6% in 1980.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Within each country there can be substantial differences in vaccination coverage. The <a href="http://www.who.int/gho/urban_health/services/dpt3_vaccination/en/">WHO reports</a> that in all regions children in the richest 20% of urban households are more likely to get immunized than children from the poorest 20% of households.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Some countries lag behind however. Ukraine stands out as having particularly low DTP vaccination rates in 2015 of 23%, falling from 98% in 1999. Ed Holt writing for the Lancet in 2013 attributed the decline to: "A combination of public mistrust in vaccinations, poor vaccine supply, and corruption in the health system".{ref}Holt, Ed., Ukraine at risk of polio outbreak, The Lancet , Volume 381 , Issue 9885 , 2244 <a href="https://www.ncbi.nlm.nih.gov/pubmed/23819156">here</a>{/ref} Therefore Ukraine is suffering from a combination of factors effecting vaccination rates from public attitudes and systemic delivery problems. Furthermore, the unrest since 2014 and Russian military intervention is likely to have worsened matters. Today only Equatorial Guinea reports even lower rates at 16%. As <a href="https://www.hrw.org/world-report/2015/country-chapters/equatorial-guinea">Human Rights Watch observes</a>, very little of the country's wealth is being directed towards the needs of citizens.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The number of under-vaccinated children in Nigeria remains high, with <a href="http://www.gavi.org/library/news/statements/2017/vaccine-progress-in-developing-countries-in-danger-of-stalling/">3.4 million children going without the DTP3 vaccine (compared with 2.9 million in India</a>).</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/share-of-children-immunized-dtp3" width="300" height="150"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Measles vaccine</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Measles is a highly contagious virus-caused disease that, despite a safe and effective vaccine being available, infects thousands of people globally. Around 90,000 people die because of measles every year, the huge majority of whom (87%) are children younger than 5. Measles vaccination has resulted in an 84% drop in measles deaths between 2000-2016.{ref}Figures are updated by the WHO here: http://www.who.int/news-room/fact-sheets/detail/measles{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The world map shows the share of children vaccinated with the first dose of measles vaccine.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>You can switch to the 'chart' view to see the global coverage against vaccines. The measles vaccine was developed in 1963. In 1983 – the first year for which global data is available – only every second child was vaccinated against measles. In the latest data this share has increased to 85% globally up from 72% in 2000.{ref}See the WHO here: <a href="http://www.who.int/mediacentre/factsheets/fs286/en/">http://www.who.int/mediacentre/factsheets/fs286/en/</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The sub-Saharan African region achieves the lowest measles vaccination rates, along with conflict-ridden and unstable countries (e.g. Syria, Afghanistan, and Iraq). But also some of the Pacific Islands – such as Papua New Guinea and Vanuatu – are performing poorly.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Today (data from 2014) 114.3 million children are vaccinated against measles every year, which is on average 313,071 children every single day.{ref}In 2014 there were <a href="https://ourworldindata.org/grapher/number-of-one-year-olds">135.2 million one-year olds</a>. Of these <a href="https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles?tab=chart">84.52% received the vaccine against measles</a>.<br> This means that 135.2 *0.8452 = 114.27 million children were vaccinated.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles" width="300" height="150"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Second dose of measles vaccine provides greater protection</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>As of 2018, the WHO estimate that 171 countries had included a second dose as part of routine immunization. Two doses are needed for a higher level of protection.{ref}Gaston De Serres, Jill Sciberras, Monika Naus, Nicole Boulianne, Bernard Duval, and Louis Rochette (1999) – Protection after Two Doses of Measles Vaccine Is Independent of Interval between Doses. In The Journal of Infectious Diseases, Volume 180, Issue 1, 1 July 1999, Pages 187–190, <a href="https://doi.org/10.1086/314847">https://doi.org/10.1086/314847</a> Online here: <a href="https://academic.oup.com/jid/article/180/1/187/990623">https://academic.oup.com/jid/article/180/1/187/990623</a>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The map here shows the coverage of the second dose (MCV2) of the measles vaccine. The current global average is 67%. The coverage is lowest in South Africa and many countries in Sub-Saharan Africa still have not introduced the vaccine into their immunization coverage.{ref}For guidelines on recommendations for the second dose of measles vaccine see here <a href="https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf">https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf</a>{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><a href="https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles-vs-share-vaccinated-against-dpt3">This scatterplot</a> compares the vaccination coverage against measles with the coverage against DTP3.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/share-of-children-vaccinated-with-mcv2" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Global decline of measles</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The second visualization shows the discussed increase of the global vaccination coverage of one-year-olds and the simultaneous decline of reported cases of the disease; from close to 1,000 cases per million people globally to 28 cases per million. This represents a 33-fold reduction.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>For country by country change over time see <a href="https://ourworldindata.org/grapher/reported-cases-of-measles">this visualization</a>.</p> <!-- /wp:paragraph --> <!-- wp:html --> <figure><iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide" width="300" height="150"></iframe></figure> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Rotavirus vaccines</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 26801 --> <!-- wp:paragraph --> <p>The first widely-used rotavirus vaccine was approved in the United States in 2006. Today, there are four oral rotavirus vaccines recommended for use by the World Health Organisation (WHO): Rotarix, RotaTeq, RotaSiil, and Rotavac.{ref}World Health Organization. (2019). <em>Rotavirus</em>. [online] Available at: <a href="https://www.who.int/immunization/diseases/rotavirus/en/">https://www.who.int/immunization/diseases/rotavirus/en/</a> [Accessed 14 Aug. 2019].{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p> Rotarix and RotaTeq are the most widely used and both have shown good efficacy against rotavirus infections in clinical trials.{ref}Ruiz-Palacios, G. M., Pérez-Schael, I., Velázquez, F. R., Abate, H., Breuer, T., Clemens, S. C., … & Cervantes, Y. (2006). <a href="https://www.nejm.org/doi/full/10.1056/nejmoa052434">Safety and efficacy of an attenuated vaccine against severe rotavirus gastroenteritis</a>. <em>New England Journal of Medicine</em>, <em>354</em>(1), 11-22.{/ref}{ref}Vesikari, T., Matson, D. O., Dennehy, P., Van Damme, P., Santosham, M., Rodriguez, Z., … & Shinefield, H. R. (2006). <a href="https://www.nejm.org/doi/full/10.1056/nejmoa052664">Safety and efficacy of a pentavalent human–bovine (WC3) reassortant rotavirus vaccine</a>. <em>New England Journal of Medicine</em>, <em>354</em>(1), 23-33.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Since the use of rotavirus vaccines have been approved, they have had a notable impact on the reduction of rotavirus-related deaths. According to a study published in 2018, the use of rotavirus vaccines prevented approximately 28,900 child deaths globally in 2016. However, as the chart shows, full vaccine use – that is a 100% coverage globally – could have prevented an additional 83,200 deaths.{ref}Troeger, C., Khalil, I. A., Rao, P. C., Cao, S., Blacker, B. F., Ahmed, T., … & Kang, G. (2018). <a href="https://jamanetwork.com/journals/jamapediatrics/fullarticle/2696431">Rotavirus vaccination and the global burden of rotavirus diarrhea among children younger than 5 years</a>. <em>JAMA Pediatrics</em>, <em>172</em>(10), 958-965.{/ref} This means that, even at the current rates of efficacy, 53% of all deaths in children under-5 from rotavirus in 2016 could have been avoided by full vaccine coverage. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In addition to saving lives, the rotavirus vaccine also reduces the burden on healthcare systems. Between 2008 and 2016 the introduction of the rotavirus vaccine has reduced the number of diarrhea-related hospital admissions on average by 40%.{ref}Aliabadi, Negar, et al. <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(19)30207-4/fulltext">"Global impact of rotavirus vaccine introduction on rotavirus hospitalisations among children under 5 years of age, 2008–16: findings from the Global Rotavirus Surveillance Network."</a> <em>The Lancet Global Health</em>7.7 (2019): e893-e903.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/avertable-deaths-from-rotavirus-with-full-vaccine-coverage"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Rotavirus vaccine could save the lives of even more children</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>If there is so much scope for saving more children’s lives, what is the reason that these children are still dying?</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>There are two key barriers to achieving the full potential of the rotavirus vaccine: immunization rates, and the efficacy of the vaccine in specific regions.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Immunisation rates are still too low</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>According to the WHO, by the end of 2018, 101 countries were using the rotavirus vaccine. The major drivers for the introduction of the vaccine are the burden of diarrheal diseases, the availability of funding, and a favourable political climate for vaccines.{ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The cost of rotavirus vaccines varies by country. For example, countries with a gross national income per capita of less than US$1,000 receive subsidies from the Global Alliance for Vaccines and Immunisation, and there the cost per dose is <a href="https://www.unicef.org/supply/files/Rotavaccine.pdf">set between US$2.10 - 3.20</a>. With additional co-financing options can reduce the costs <a href="https://www.sabin.org/sites/sabin.org/files/frederic_debellut.pdf">down to US$0.13</a>. In high-income countries, such as the US, the cost per dose is between <a href="https://www.cdc.gov/vaccines/programs/vfc/awardees/vaccine-management/price-list/index.html">US$70 and 95</a></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Countries are more likely to introduce the vaccine if the political environment is favourably disposed towards them. For example, if a country has set a high priority on achieving the Millennium Development Goal targets or the introduction of vaccines is seen as a positive news story, especially during election years.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Burchett, H. E. D., Mounier-Jack, S., Griffiths, U. K., Biellik, R., Ongolo-Zogo, P., Chavez, E., … & Molla, M. (2012). <a href="https://academic.oup.com/heapol/article/27/suppl_2/ii5/594662">New vaccine adoption: qualitative study of national decision-making processes in seven low-and middle-income countries</a>. <em>Health policy and planning</em>, <em>27</em>(suppl_2), ii5-ii16.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p> The vaccine is only given to children – it’s recommended that the vaccination should be initiated 15 weeks after birth and finished by the 32nd week. However, the global coverage is still very low: it is estimated that just 35% of under one-year-olds were vaccinated in 2018.{ref}World Health Organization (2019). <em>Immunization coverage</em>. [online] Available at: <a href="https://www.who.int/news-room/fact-sheets/detail/immunization-coverage">https://www.who.int/news-room/fact-sheets/detail/immunization-coverage</a> [Accessed 14 Aug. 2019].{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The map shows the WHO estimates on the share of one-year olds who received the full recommended dosage of the vaccine (two immunizations for Rotarix vaccine or three immunizations for RotaTeq vaccine). For many countries where data coverage is low, it’s expected that the share of infants receiving the vaccine is very low. Some countries however did see rapid increases in rates of immunization. In a period of only a few years countries including <a href="https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine?tab=chart&time=2011..2018&country=SDN+GMB+MWI">Sudan, Malawi and Gambia</a> have increased immunisation rates from below 10% to 80-95% – click on the country to see the change over time.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe style="width: 100%; height: 600px; border: 0px none;" src="https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Vaccine efficacy differs by region</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Since most <a href="https://ourworldindata.org/grapher/child-deaths-from-rotavirus">rotavirus cases</a> occur in Sub-Saharan Africa where <a href="https://ourworldindata.org/grapher/child-mortality-rate-from-rotavirus?tab=chart">mortality from rotavirus infection is also the highest</a>, it is essential to increase and maintain high immunisation coverage in this region. However, in addition to delivering the vaccine for those who need it, we also need to work on improving its efficacy.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Vaccine efficacy for the rotavirus vaccine is defined as the percentage reduction of the rate of diarrhea incidences in vaccinated versus unvaccinated groups of children. It is well established that the efficacy of the rotavirus vaccine is not the same across all countries — in countries with high child mortality rates the vaccine shows much lower efficacy.{ref}Clark, Andrew, et al. <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext">"Efficacy of live oral rotavirus vaccines by duration of follow-up: a meta-regression of randomised controlled trials."</a> <em>The Lancet Infectious Diseases</em> (2019).{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The chart is from a recent study by Clark et <em>al.</em>, which looked at how the efficacy of live oral rotavirus vaccines changes in different countries following vaccination. The chart shows that in countries with high child mortality rates, not only is the immediate vaccine efficacy lower – 98% in low child mortality countries versus 66% in high child mortality countries – but also the vaccine efficacy decreases faster in high child mortality countries over time.{ref}The <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext">Clark et al.</a> (2019) study defined low child mortality rate as less than 1.3% of newborns; medium mortality rate as between 1.35% and 2.81%; and high mortality rate as more than 2.81%{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p> Five years after vaccination, the rotavirus vaccine reduces the chances of getting diarrhea by 90% in low child mortality countries and only by 30% in high mortality countries.</p> <!-- /wp:paragraph --> <!-- wp:image {"align":"center","id":24252,"linkDestination":"custom"} --> <div class="wp-block-image"><figure class="aligncenter"><a href="https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1.png"><img src="https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1-748x550.png" alt="" class="wp-image-24252"/></a></figure></div> <!-- /wp:image --> <!-- wp:paragraph --> <p>The table shows how good the rotavirus vaccine is at preventing severe diarrhea and reducing hospitalization due to diarrhea in children under-5 in different regions.{ref}Lamberti, L. M., Ashraf, S., Walker, C. L. F., & Black, R. E. (2016). <a href="https://www.ingentaconnect.com/content/wk/inf/2016/00000035/00000009/art00016">A systematic review of the effect of rotavirus vaccination on diarrhea outcomes among children younger than 5 years</a>. <em>The Pediatric Infectious Disease Journal</em>, <em>35</em>(9), 992-998.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p> In high-income countries, rotavirus vaccination has been shown to reduce the cases of severe rotavirus diarrhea by 91% and hospitalization by 94%. In Eastern Asia and Latin America, the effectiveness rates are lower but still high – preventing 88% and 80% of severe diarrhea cases, respectively. However, effectiveness in South Asia and Sub-Saharan Africa is significantly lower, only reducing severe diarrhea in around half of the cases.</p> <!-- /wp:paragraph --> <!-- wp:shortcode --> <table><thead><tr><th scope="col" colSpan="1">Outcome </th><th scope="col" colSpan="1">Region</th><th scope="col" colSpan="1">Vaccine effectivness</th></tr></thead><tbody><tr><td colSpan="1" rowspan="5">Severe rotavirus diarrhea</td><td colSpan="1" rowspan="1">Developed</td><td colSpan="1" rowspan="1">91%</td></tr><tr><td colSpan="1" rowspan="1">Eastern Asia and Southeast Asia</td><td colSpan="1" rowspan="1">88%</td></tr><tr><td colSpan="1" rowspan="1">Latin America and Caribbean</td><td colSpan="1" rowspan="1">80%</td></tr><tr><td colSpan="1" rowspan="1">Southern Asia</td><td colSpan="1" rowspan="1">50%</td></tr><tr><td colSpan="1" rowspan="1">Sub-Saharan Africa</td><td colSpan="1" rowspan="1">46%</td></tr><tr><td colSpan="1" rowspan="4">Hospitalization due to rotavirus infection</td><td colSpan="1" rowspan="1">Developed</td><td colSpan="1" rowspan="1">94%</td></tr><tr><td colSpan="1" rowspan="1">Eastern Asia and Southeast Asia</td><td colSpan="1" rowspan="1">94%</td></tr><tr><td colSpan="1" rowspan="1">Latin America and Caribbean</td><td colSpan="1" rowspan="1">84%</td></tr><tr><td colSpan="1" rowspan="1">Sub-Saharan Africa</td><td colSpan="1" rowspan="1">58%</td></tr></tbody></table> <!-- /wp:shortcode --> <!-- wp:paragraph --> <p>The reasons for different responses to the vaccine are not entirely clear.{ref}Patel, M., Shane, A. L., Parashar, U. D., Jiang, B., Gentsch, J. R., & Glass, R. I. (2009). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3673012/#R3">Oral rotavirus vaccines: how well will they work where they are needed most?</a>. <em>The Journal of Infectious Diseases</em>, <em>200</em>, S39-S48.{/ref} {ref}Parker, E. P., Ramani, S., Lopman, B. A., Church, J. A., Iturriza-Gomara, M., Prendergast, A. J., & Grassly, N. C. (2018). <a href="https://www.futuremedicine.com/doi/10.2217/fmb-2017-0128?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dwww.ncbi.nlm.nih.gov&">Causes of impaired oral vaccine efficacy in developing countries</a>. <em>Future microbiology</em>, <em>13</em>(1), 97-118.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p> It is likely that the gut responses to the oral rotavirus vaccines in children in lower-income countries are different. This may be due to a variety of causes, including <a href="https://ourworldindata.org/micronutrient-deficiency">micronutrient deficiencies</a>, pre-vaccination exposure to certain pathogens, and the presence of chronic conditions such as <a href="https://ourworldindata.org/malaria">malaria</a> or <a href="https://ourworldindata.org/hiv-aids">HIV</a>. Overall, the poor gut response to the live vaccine means the efficacy of the vaccine is reduced. Taking all of the above mentioned points into account, there are several interventions that could increase the benefits of the rotavirus vaccine even further. In addition to increasing the vaccine coverage, improving nutritional health (of both infants and mothers) and improving hygiene and sanitation conditions (to lower the prevalence of damaging pathogens) could have positive effects on the vaccine’s efficacy.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>We are still at quite an early stage of the rotavirus vaccine use. Although the vaccine has brought huge benefits already, it could go even further. Improving vaccination coverage, particularly across Sub-Saharan Africa and South Asia is key to continued reduction of childhood deaths from diarrhea. Even at moderate levels of vaccine efficacy, a significant number of additional additional child deaths could be prevented every year. The bar chart above that shows the number of preventable deaths illustrates the potential for extended vaccine coverage to save many more lives. And this is already taking into account the regional differences in the vaccine’s effectiveness.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In addition to increased coverage, improving the effectiveness of the vaccine would go even further in tackling one of the leading causes of death.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>Pneumococcal vaccines</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 27064 --> <!-- wp:paragraph --> <p>There are a number of ways we could reduce the number of children dying from pneumonia, including eliminating the major risk factors such as <a href="https://ourworldindata.org/hunger-and-undernourishment">undernutrition</a> and <a href="https://ourworldindata.org/indoor-air-pollution">air pollution</a>, and providing better <a href="https://ourworldindata.org/grapher/pneumonia-careseeking">access to treatment</a>.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But we have another highly effective intervention: a <a href="https://ourworldindata.org/vaccination">vaccine</a> against the major pathogen responsible for pneumonia in children. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><em>Streptococcus pneumoniae </em>is the leading cause of pneumonia in children under 5 — it was responsible for 52% of all fatal pneumonia cases in children in 2016.{ref}Troeger, C., Blacker, B., Khalil, I. A., Rao, P. C., Cao, J., Zimsen, S. R., ... & Adetifa, I. M. O. (2018). <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(18)30310-4/fulltext">Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory infections in 195 countries, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016.</a><em> The Lancet Infectious Diseases</em>, <em>18</em>(11), 1191-1210.{/ref} Pneumococcal vaccines are vaccines that target <em>S. pneumoniae</em> bacteria. Here we look at their effectiveness and how we can maximise the number of children they save.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>The coverage of pneumococcal vaccines is still low</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Since the World Health Organisation (WHO) started recommending including pneumococcal vaccines in national immunisation programmes for children in 2007, there has been a progressive increase in the number of countries using the vaccine. You can see the uptake in the vaccine across the world using the ‘play’ button on the map below. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But the coverage of pneumococcal vaccines is still low in many countries. In India and Nigeria – the two countries with the <a href="https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5">greatest number</a> of childhood deaths from pneumonia in 2019 – only 44% and 58% of one-year-olds are vaccinated, respectively. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In 2018, less than half (47%) of one-year-olds in the world received the full course of pneumococcal vaccination. This means that 55 million children who could be protected by the vaccine are still not vaccinated against it — an appallingly high number for a vaccine that not only protects from pneumonia, the leading cause of childhood death, but also a range of other diseases (as discussed below).{ref}Who.int. (2019) – <a href="https://www.who.int/news-room/fact-sheets/detail/immunization-coverage"><em>Immunization coverage</em></a>. [online] [Accessed 10 Sep. 2019]. <a href="http://view-hub.org/viz/">http://view-hub.org/viz/</a> (Go to PCV —> PCV - Vaccine Access —> Children without Access){/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>How do pneumococcal vaccines work?</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p><em>Streptococcus pneumonia</em>, often simply referred to as pneumococcus, is a bacterium that is often found in the upper respiratory tract of healthy people. Generally, the bacterium is harmless or causes milder illnesses such as bronchitis, sinusitis, and ear infections. Pneumococcal vaccines are effective against these milder illnesses as well, but importantly also protects from what is called pneumococcal invasive disease (PID). PID occurs when the pneumococcus moves from colonizing the upper respiratory tract to colonizing sites that are normally sterile, such as blood, cerebrospinal fluid or pleural cavity (fluid-filled space surrounding the lungs).{ref}Hanada, S., Pirzadeh, M., Carver, K. Y., & Deng, J. C. (2018). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6250824/">Respiratory Viral Infection-Induced Microbiome Alterations and Secondary Bacterial Pneumonia.</a> <em>Frontiers in immunology</em>, <em>9</em>, 2640.{/ref} Bacterial invasion leads to life-threatening diseases such as sepsis, meningitis and severe pneumonia. </p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/child-deaths-from-streptococcus-by-disease" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:paragraph --> <p>There are two types of pneumococcal vaccines available: conjugated polysaccharide pneumococcal vaccine (PCV) and non-conjugated polysaccharide pneumococcal vaccine (PPSV). Both vaccines are designed to elicit immune responses against multiple serotypes of pneumococcus, which are defined by the different immune responses to the sugars found on the bacterial surface.{ref}Song, J. Y., Nahm, M. H., & Moseley, M. A. (2013). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3546102/">Clinical implications of pneumococcal serotypes: invasive disease potential, clinical presentations, and antibiotic resistance</a>. <em>Journal of Korean medical science</em>, <em>28</em>(1), 4-15.{/ref} To be broadly effective, the vaccines need to protect against a certain number of these pneumococcal serotypes, but it is not necessary to include all possible serotypes because only a limited subset is responsible for 70%-80% of invasive pneumococcal disease.{ref}The number of serotypes included in the vaccine is generally indicated in its name, e.g. PCV13 is pneumococcal conjugate vaccine effective against 13 bacterial serotypes. Vaccines including progressively more serotypes have been introduced over the years, PCV7 was introduced in 2000 and today the most commonly used PCV13 was introduced in 2010.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Hausdorff, W. P., Feikin, D. R., & Klugman, K. P. (2005). <a href="https://www.ncbi.nlm.nih.gov/pubmed/15680778/">Epidemiological differences among pneumococcal serotypes.</a> <em>The Lancet infectious diseases</em>, <em>5</em>(2), 83-93.{/ref} However, as we’ll discuss later, this variety of different pneumococcal serotypes is important to keep in mind because as vaccine coverage increases we may see a replacement of the vaccine-included serotypes with the less dominant ones, which will mean new vaccine versions will be required. <br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>While there are two types of pneumococcal vaccines available, for children under two years old only the conjugated (i.e. PCV) vaccines are recommended because the non-conjugated versions (i.e. PPSV) are not effective at such a young age.{ref}The current non-conjugate vaccine, PPSV23, is generally only given to adults or as a single dose following two immunisations with PCV13 in children older than 2.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Golos, M., Eliakim‐Raz, N., Stern, A., Leibovici, L., & Paul, M. (2016). <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD012306/full">Conjugated pneumococcal vaccine versus polysaccharide pneumococcal vaccine for prevention of pneumonia and invasive pneumococcal disease in immunocompetent and immunocompromised adults and children.</a> <em>Cochrane Database of Systematic Reviews</em>, (8).{/ref} </p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>How effective are pneumococcal vaccines?</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>In clinical trials PCV has shown 80% efficacy in reducing invasive pneumococcal disease caused by the bacterial serotypes included in the vaccine formulation. Vaccinated children are 27% less likely to be diagnosed with pneumonia and 11% less likely to die from it.{ref}The 27% refers to X-ray-defined cases of pneumonia. For clinically defined pneumonia, a less accurate diagnosis than X-ray-defined cases, the number is 6%. Both of these indicators refer to cases of pneumonia caused by any pathogen not only pneumococcus. Lucero, M. G., Dulalia, V. E., Nillos, L. T., Williams, G., Parreño, R. A. N., Nohynek, H., ... & Makela, H. (2009). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6464899/">Pneumococcal conjugate vaccines for preventing vaccine‐type invasive pneumococcal disease and X‐ray defined pneumonia in children less than two years of age</a>. <em>Cochrane Database of Systematic Reviews</em>, (4).{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Several studies have attempted to estimate how many lives PCV vaccination has saved and could possibly save. One <em>Lancet </em>study concluded that between 2000 and 2015, in 120 countries the number of childhood deaths caused by pneumococcus fell from 600,000 to 294,000 — a decline of 54%. Most of this decline was attributed to the PCV vaccines: over this period, it’s estimated these vaccines saved the lives of 250,000 children. The majority of these deaths would have been caused by pneumonia, but the vaccine also prevented deaths from pneumococcal meningitis and other diseases.{ref}Wahl, B., O'Brien, K. L., Greenbaum, A., Majumder, A., Liu, L., Chu, Y., ... & Rudan, I. (2018). <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30247-X/fulltext">Burden of Streptococcus pneumoniae and Haemophilus influenzae type b disease in children in the era of conjugate vaccines: global, regional, and national estimates for 2000–15.</a><em> The Lancet Global Health</em>, <em>6</em>(7), e744-e757.{/ref} </p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>How many child deaths could be averted by pneumococcal vaccines?</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The chart shows how estimates of the potential impact of the pneumococcal vaccine.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>It is based on a recent study published in <em>The Lancet Global Health</em> journal, which calculated that if the PCV vaccine coverage would reach at least the levels of the <a href="https://ourworldindata.org/grapher/share-of-children-immunized-dtp3">vaccination against diphtheria, tetanus and pertussis</a> (DTP3), the lives of 399,000 children under 5 could be saved.{ref}Chen, C., Liceras, F. C., Flasche, S., Sidharta, S., Yoong, J., Sundaram, N., & Jit, M. (2019). <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30422-4/fulltext">Effect and cost-effectiveness of pneumococcal conjugate vaccination: a global modelling analysis.</a><em> The Lancet Global Health</em>, <em>7</em>(1), e58-e67.{/ref} Additionally the researchers estimate that 54.6 million pneumonia episodes annually could be averted.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>These number estimate the impact of the PCV vaccination relative to a world without that vaccine – since the vaccine is already used it means that some of these lives are already being saved by the PVC vaccination. However, in many countries <a href="https://ourworldindata.org/grapher/diphtheria-tetanus-pertussis-vaccine-vs-pneumococcal-vaccine-coverage">PCV vaccination rates still fall far below the DTP3 rates</a>, making clear that we still haven’t used the pneumococcal vaccine to its full potential.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/pneumococcal-vaccination-averted-deaths" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>What can we do to improve the coverage and effectiveness of pneumococcal vaccines?</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>A continued increase in immunization coverage and the introduction of PCV vaccines into countries which don’t yet use them is important if we want to make use of the full potential of pneumococcal vaccines. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>PCV vaccines are amongst the most expensive vaccines in national immunisation programmes. The price ranges from $3.05 per dose in GAVI{ref} GAVI (Global Alliance for Vaccines and Immunisation) is a non-profit organisation that provides access to vaccination programs for low-income countries by providing financial support and individual expertise.{/ref} supported low-income countries to $169 in high-income countries such as the United States.{ref}O'Brien, K. L. (2018). <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc">When less is more: how many doses of PCV are enough?.</a><em> The Lancet Infectious Diseases</em>, <em>18</em>(2), 127-128.{/ref} For low-middle-income countries who are transitioning from GAVI support the increasing future costs of vaccination place a considerable strain on national healthcare budgets.{ref}For example Kenya has recently entered a transition phase during which it will pay a larger and larger portion of the PCV vaccine cost. By 2027 Kenya will have to pay the full $9 price for a three-dose course child vaccination. The 2016 <a href="https://databank.worldbank.org/Kenya-healthcare-per-capita-/id/58f0a890">per capita healthcare expenditure in Kenya</a> was around $66 (5% of the GDP), clearly $9 per child is not a trivial cost.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Simonsen, L., van Wijhe, M., & Taylor, R. (2019). <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext">Are expensive vaccines the best investment in low-income and middle-income countries?</a>. <em>The Lancet Global Health</em>, <em>7</em>(5), e548-e549.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Ojal, J., Griffiths, U., Hammitt, L. L., Adetifa, I., Akech, D., Tabu, C., ... & Flasche, S. (2019). <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext">Sustaining pneumococcal vaccination after transitioning from Gavi support: a modelling and cost-effectiveness study in Kenya.</a><em> The Lancet Global Health</em>, <em>7</em>(5), e644-e654.{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>But given the high burden of pneumococcal diseases, even at high prices, PCV vaccines are considered to be cost-effective, with an estimated return of investment in low- and middle-income countries of around 3.{ref}The return of investment was estimated for a projected coverage for individual countries for the decade between 2011 and 2020. It means that the economic benefits (as measured by the costs of vaccination program subtracted from the reduced costs of treatment and productivity loss) of using the vaccine are 3 times higher than no vaccine use. <br>To reduce costs, some countries may also consider switching to a two rather than three dose immunization schedule, but more research on the effectiveness of this schedule in different countries is needed. See O'Brien et al. (2018) reference.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Nakamura, M. M., Tasslimi, A., Lieu, T. A., Levine, O., Knoll, M. D., Russell, L. B., & Sinha, A. (2011). <a href="https://academic.oup.com/inthealth/article-lookup/doi/10.1016/j.inhe.2011.08.004">Cost effectiveness of child pneumococcal conjugate vaccination in middle-income countries.</a> <em>International health</em>, <em>3</em>(4), 270-281.<br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Ozawa, S., Clark, S., Portnoy, A., Grewal, S., Brenzel, L., & Walker, D. G. (2016). <a href="https://www.healthaffairs.org/doi/full/10.1377/hlthaff.2015.1086?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed">Return on investment from childhood immunization in low-and middle-income countries, 2011–20.</a> <em>Health Affairs</em>, <em>35</em>(2), 199-207.<br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Center, I. V. A. (2017). <a href="https://www.jhsph.edu/ivac/wp-content/uploads/2018/05/PCVEvidenceBase-Jan2017.pdf">The evidence base for pneumococcal conjugate vaccines (PCVs): data for decision-making around PCV use in childhood.</a> <em>Baltimore (MD): Johns Hopkins University</em>.<br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Goldblatt, D., Southern, J., Andrews, N. J., Burbidge, P., Partington, J., Roalfe, L., ... & Snape, M. D. (2018). <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30654-0/fulltext">Pneumococcal conjugate vaccine 13 delivered as one primary and one booster dose (1+ 1) compared with two primary doses and a booster (2+ 1) in UK infants: a multicentre, parallel group randomised controlled trial.</a> <em>The Lancet Infectious Diseases</em>, <em>18</em>(2), 171-179.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>O'Brien, K. L. (2018). <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc">When less is more: how many doses of PCV are enough?.</a><em> </em><em>The Lancet Infectious Diseases</em>, <em>18</em>(2), 127-128.{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>PCV vaccines include a limited subset of possible pneumococcal serotypes. The distribution of pneumococcal serotypes is known to vary between countries and PCV vaccines include the ones that are most common globally. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Which non-vaccine serotypes are most common in a particular country, may affect the potential for a particular vaccine’s impact. However, not all countries collect data on serotype distribution, and an assessment of the potential impact is therefore compromised.{ref}Adegbola, R. A., DeAntonio, R., Hill, P. C., Roca, A., Usuf, E., Hoet, B., & Greenwood, B. M. (2014). <a href="https://www.ncbi.nlm.nih.gov/pubmed/25084351">Carriage of Streptococcus pneumoniae and other respiratory bacterial pathogens in low and lower-middle income countries: a systematic review and meta-analysis</a>. <em>PloS one</em>, <em>9</em>(8), e103293.{/ref} {ref}Megiddo, I., Klein, E., & Laxminarayan, R. (2018). <a href="https://gh.bmj.com/content/3/3/e000636">Potential impact of introducing the pneumococcal conjugate vaccine into national immunisation programmes: an economic-epidemiological analysis using data from India.</a><em> BMJ global health</em>, <em>3</em>(3), e000636.{/ref} {ref}Johnson, H. L., Deloria-Knoll, M., Levine, O. S., Stoszek, S. K., Hance, L. F., Reithinger, R., ... & O'Brien, K. L. (2010). <a href="https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1000348">Systematic evaluation of serotypes causing invasive pneumococcal disease among children under five: the pneumococcal global serotype project.</a><em>PLoS medicine</em>, <em>7</em>(10), e1000348.{/ref} Notably, since the PCV vaccine was introduced, there has been a rise in pneumococcal invasive disease incidences caused by the less common serotypes. This suggests that, by reducing the prevalence of vaccine-included serotypes, the vaccine unintentionally provides space for non-vaccine serotypes, against which it works less well.{ref}World Health Organization. (2010). <a href="https://www.who.int/wer/2010/wer8543.pdf?ua=1">Changing epidemiology of pneumococcal serotypes after introduction of conjugate vaccine: July 2010 report.</a><em> Weekly Epidemiological Record [Relevé épidémiologique hebdomadaire</em>], <em>85</em>(43), 434-436.{/ref} This means that the vaccine's effectiveness may decrease over time, if the serotype formulation of PCV is not continually reevaluated. In the future, new versions of pneumococcal vaccines may be needed that work better independently of the bacterial serotype. Such vaccines are already in development.{ref}Pichichero, M. E. (2017). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277969/">Pneumococcal whole-cell and protein-based vaccines: changing the paradigm</a>. <em>Expert review of vaccines</em>, <em>16</em>(12), 1181-1190.{/ref} {ref}Ginsburg, A. S., Nahm, M. H., Khambaty, F. M., & Alderson, M. R. (2012). Issues and challenges in the development of pneumococcal protein vaccines. Expert review of vaccines, 11(3), 279-285{/ref} <br></p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>Hepatitis B vaccine</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The chart here shows the coverage for Hepatitis B vaccination.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Hepatitis B (HepB) is a highly contagious viral infection that attacks the liver and is transmitted through contact with the blood or other body fluids of an infected person. As the chart shows, it is estimated that about 100,000 people die each year of chronic liver disease due to hepatitis B. The WHO recommends that all infants should receive their first dose of vaccine as soon as possible after birth, preferably within 24 hours.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/immunization-hepb3-of-one-year-old-children" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Haemophilus influenzae type b vaccine</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Haemophilus influenzae type b (Hib) is a bacterial infection that causes meningitis and pneumonia transmitted through the respiratory tract from infected to susceptible individuals. The chart here shows the coverage for Hib vaccination.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/hib-vaccine" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Polio vaccine</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The chart here shows the coverage of the polio vaccine.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Poliomyelitis (OPV, IPV) is a highly infectious viral disease. Once the poliovirus invades the nervous system it can cause irreversible paralysis in a matter of hours. No cure exists for polio, only treatment to alleviate symptoms. As we detail in our <a href="https://owid.cloud/polio">entry on polio</a> the world is on its way to eradicate the disease thanks to the vaccine against the virus: While in the 1980s there were 350,000 paralytic cases of polio every year, the world saw only 42 cases in 2016. </p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/polio-vaccine-coverage-of-one-year-olds" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Tuberculosis vaccine (BCG)</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 28979 --> <!-- wp:paragraph --> <p>The chart here shows the coverage of the BCG vaccine, which protects against tuberculosis.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Developed more than a century ago, bacille Calmette–Guérin vaccine (BCG) is currently the only vaccine available against tuberculosis (TB). </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Close to 4 billion people have been vaccinated with BCG - this makes it the most widely used vaccine in the world.{ref}Kendig, E. L., Wilmott, R. W., & Chernick, V. (2012). <a href="https://www.sciencedirect.com/science/article/pii/B9780323448871000298"><em>Kendig and Chernick's disorders of the respiratory tract in children</em></a>. 9th ed. Elsevier Health Sciences.{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>BCG vaccine is based on a reduced-virulence strain of <em>Mycobacterium bovis</em>, a bacterium that is closely related to <em>Mycobacterium tuberculosis</em> - the pathogen that causes TB. BCG vaccine was already used in the 1920s in Belgium and France in small trials and after the Second World War its use was expanded to vaccinate children across Europe. In 1950s the WHO started recommending the use of BCG globally. <br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>BCG is effective at protecting children and adolescents from severe forms of TB and meningitis.{ref} Rodrigues, L. C., Mangtani, P., & Abubakar, I. (2011).<a href="https://www.bmj.com/content/343/bmj.d5974.full"> How does the level of BCG vaccine protection against tuberculosis fall over time?</a>. <em>Bmj</em>, <em>343</em>, d5974.{/ref} {ref}Rodrigues, L. C., Diwan, V. K., & Wheeler, J. G. (1993). <a href="https://academic.oup.com/ije/article-abstract/22/6/1154/650235">Protective effect of BCG against tuberculous meningitis and miliary tuberculosis: a meta-analysis.</a><em>International journal of epidemiology</em>, <em>22</em>(6), 1154-1158.{/ref} However, studies have shown that the length of protection provided by the vaccine varies greatly depending on the populations studied: from 15 years in the UK to 50–60 years in Alaska.{ref}Sterne, J. A. C., Rodrigues, L. C., & Guedes, I. N. (1998).<a href="https://www.ingentaconnect.com/content/iuatld/ijtld/1998/00000002/00000003/art00005"> Does the efficacy of BCG decline with time since vaccination?.</a><em>The international journal of tuberculosis and lung disease</em>, <em>2</em>(3), 200-207.{/ref} {ref}Aronson, N. E., Santosham, M., Comstock, G. W., Howard, R. S., Moulton, L. H., Rhoades, E. R., & Harrison, L. H. (2004). <a href="https://jamanetwork.com/journals/jama/article-abstract/198681">Long-term efficacy of BCG vaccine in American Indians and Alaska Natives: a 60-year follow-up study.</a><em>Jama</em>, <em>291</em>(17), 2086-2091.{/ref} The reason for such variability is not clear, but factors such as different vaccine seed strains used for immunization and pre-existing immunity in people already exposed to other mycobacteria strains may be important. <br>Notably, BCG vaccine does not protect people from primary infections, that is it does not prevent people from getting infected with <em>M. tuberculosis </em>bacterium in the first place. BCG also does not prevent activation of latent TB if a person has already been infected. Therefore, the vaccine has limited effect on prevention of <em>M. tuberculosis </em>spread in a population.{ref} https://www.who.int/biologicals/areas/vaccines/bcg/en/ {/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Yellow fever vaccine</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The chart here shows the coverage of the yellow fever vaccine.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Yellow fever (YF) is a viral disease transmitted by infected mosquitoes. There are 40 countries and territories at risk for yellow fever in Africa and the Americas and of these 36 include yellow fever vaccination in their routine immunization schedules. Total, vaccine coverage in 2018 was estimated at 49%.{ref}<a href="https://www.who.int/news-room/fact-sheets/detail/immunization-coverage">https://www.who.int/news-room/fact-sheets/detail/immunization-coverage</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/yellow-fever-vaccine-coverage" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading --> <h2>Definitions and Measurement</h2> <!-- /wp:heading --> <!-- wp:heading {"level":4} --> <h4>Calculating coverage</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The coverage is calculated as the proportion of persons in a target age group who received a vaccine dose. Dates of vaccination are either taken from a child’s home-based record, recorded based on caregiver recall, or from health facility records.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>While appearing straightforward enough, several methodological problems of household survey respondent data on vaccination have been well documented.{ref}Daniel A. Salmon, Philip J. Smith, Ann Marie Navar, William K. Y. Pan, Saad B. Omer, James A. Singleton, Neal A. Halsey; Measuring Immunization Coverage among Preschool Children: Past, Present, and Future Opportunities, <em>Epidemiologic Reviews</em>, Volume 28, Issue 1, 1 August 2006, Pages 27–40, <a href="https://doi.org/10.1093/epirev/mxj001">https://doi.org/10.1093/epirev/mxj001</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Questions have arisen about how accurately parents can recall child immunization history and the limitations of phone calls to collect data.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Even accurately estimating target populations in low-income settings can be difficult and discrepancies have been found when comparing country-reported figures with independent surveys.{ref}"Global childhood immunization coverage growing at only half the officially reported rate, IHME study" online here: <a href="http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme">http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Furthermore, childhood vaccinations are rarely considered altogether. The DTP3 vaccination tends to be the vaccination most often used as a marker of strength in a country’s immunization programs, since three administrations of the vaccination are required.{ref}Other vaccines measured by the WHO and UNICEF are HepB3, Hib3, MCV and PAB.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>National and subnational coverage</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>National coverage rates are what is focused upon, but even when national coverage are high, subnational coverage can reveal inequities, which is why the WHO and UNICEF are increasing efforts to gather high quality subnational coverage data.{ref}See: <a href="http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/">http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/</a>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In 2015 coverage estimates at the district level were only reported for 158 of the 194 WHO Member States. National data only provides part of the picture of immunization coverage. Different levels of coverage data, including at sub-national or district level is useful for gaining an understanding of where there might be clusters of under- or un-vaccinated children.</p> <!-- /wp:paragraph --> <!-- wp:heading --> <h2>Data Sources</h2> <!-- /wp:heading --> <!-- wp:heading {"level":4} --> <h4>World Health Organization - Immunization surveillance, assessment and monitoring</h4> <!-- /wp:heading --> <!-- wp:list --> <ul><li><strong>Data:</strong> Immunization coverage, system indicators and schedule, and disease incidence</li><li><strong>Geographical coverage:</strong> WHO member nations</li><li><strong>Time span:</strong> 1980 onwards for many countries</li><li><strong>Available at:</strong> Online <a href="http://www.who.int/immunization/monitoring_surveillance/data/en/">here</a></li></ul> <!-- /wp:list --> <!-- wp:heading {"level":4} --> <h4>UNICEF</h4> <!-- /wp:heading --> <!-- wp:list --> <ul><li><strong>Data:</strong> Percent of one-year-olds immunized</li><li><strong>Geographical coverage:</strong> UN member nations</li><li><strong>Time span:</strong> 1980 onwards for many countries</li><li><strong>Available at:</strong> Online from UNICEF <a href="http://web.archive.org/web/20150709064229/http://data.unicef.org/child-health/immunization">here</a>. Also available via Gapminder <a href="http://www.gapminder.org/data/">here</a> (search "vaccine" to find the data).</li></ul> <!-- /wp:list --> <!-- wp:heading {"level":4} --> <h4>Further reading</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>More information about vaccines in general can be found on the World Health Organization (WHO) page on <a href="http://www.who.int/topics/immunization/en/">immunization</a>.</p> <!-- /wp:paragraph --> | { "id": "wp-1455", "slug": "vaccination", "content": { "toc": [], "body": [ { "type": "text", "value": [ { "text": "This article was first published in July 2015; last revised in October 2022.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "url": "#all-charts", "children": [ { "text": "See all interactive charts on vaccination \u2193", "spanType": "span-simple-text" } ], "spanType": "span-link" } ], "spanType": "span-bold" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "We thank Stephanie Shendale, Sarah Loving, Anita Milicic, and Andy Pollard for helpful comments and suggestions on earlier draft versions of this entry.", "spanType": "span-simple-text" } ], "spanType": "span-italic" } ], "parseErrors": [] }, { "text": [ { "text": "Related writing", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "list", "items": [ { "type": "text", "value": [ { "url": "https://ourworldindata.org/smallpox", "children": [ { "text": "Smallpox", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2014 How has vaccination eradicated smallpox?", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "url": "https://ourworldindata.org/eradication-of-diseases", "children": [ { "text": "Disease eradication", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2014 How and which diseases can be eradicated?", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "url": "https://ourworldindata.org/pneumonia#pneumococcal-vaccines", "children": [ { "text": "Child & ", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "url": "https://ourworldindata.org/child-mortality#", "children": [ { "text": "infant", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "url": "https://ourworldindata.org/pneumonia#pneumococcal-vaccines", "children": [ { "text": " mortality", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2014 What are children dying from and how can we prevent it?", "spanType": "span-simple-text" } ], "parseErrors": [] } ], "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Not every child who should be vaccinated is vaccinated", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Global vaccine coverage", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "This chart shows the global vaccination coverage of one-year-olds with some of the most important vaccines recommended by the WHO. For many essential vaccines coverage is now much higher than 80%. However, the rates of vaccination are still not sufficient. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "If you click the play button you see that the coverage for most vaccines has increased substantially over time.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The vaccine against diphtheria, tetanus and pertussis, is often used as the key metric for global vaccination coverage because it is a good indicator for access to routine immunization services. In 2018, coverage of the third dose of DTP was 86%. This means that out of 135 million under-one-year-olds more than 19 million did not receive full immunization. The coverage of the first dose of DTP was 90% indicating that ", "spanType": "span-simple-text" }, { "children": [ { "text": "13.5 million children were not vaccinated", "spanType": "span-simple-text" } ], "spanType": "span-bold" }, { "text": " in 2018. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In 2018, only 35% of children globally received the rotavirus vaccine, which protects children from ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/diarrheal-diseases", "children": [ { "text": "diarrheal diseases", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2014 ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/child-mortality#what-are-children-dying-from", "children": [ { "text": "one of the leading causes", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " of child mortality. Similarly, pneumococcal vaccine that protects children from ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/pneumonia", "children": [ { "text": "pneumonia", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2014 the leading cause of child mortality \u2014 only reached 47% of one-year-olds.{ref}This and other numbers in this entry are based on the estimates by the World Health Organisation. The coverage estimates are calculated by dividing the total number of vaccinations given by the number of children in the target population. Target population size is usually based on census population projections.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "This means that there may be children in the target population that for medical reasons should be exempt from vaccination. These medical reasons may include factors such as allergies to vaccine components or severe immunodeficiencies. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Notably, such cases are very rare and would have little effect on global coverage numbers. For example, ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4783279/", "children": [ { "text": "a study", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " from 2003 identified severe allergic reaction in only 0.000063% of all vaccinations, that's 0.63 cases per million vaccinations. In addition, vaccines are always being improved with fewer ingredients that may cause allergic reactions. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Vaccination of children with immunodeficiencies generally needs to be assessed by a specialist. Especially, for vaccine that are based on a live pathogens. For example, ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/immunization/policy/Immunization_routine_table1.pdf", "children": [ { "text": "WHO recommends", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " vaccinating HIV-positive children with measles vaccine if child's HIV infection is asymptomatic or not severe. Similarly, children with severe immunodeficiency syndrome (SCID), a genetic disorder that causes defects in immune system, are ", "spanType": "span-simple-text" }, { "url": "https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/severe-combined-immunodeficiency-scid", "children": [ { "text": "safely vaccinated", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " with many vaccines before SCID is even diagnosed, but it's recommended not to vaccinate them with live vaccines. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In fact, one of the reasons it is important to increase vaccination rates is that those children and adults who for medical reasons cannot be vaccinated would still be protected from diseases through ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity", "children": [ { "text": "herd immunity", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref} ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds?time=1980..2015", "type": "prominent-link", "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/global-vaccination-coverage", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Prosperity and vaccination coverage", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Why do not all children in the world receive vaccinations?", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "This chart shows that it is in poor countries where vaccination coverage is low. The vaccine coverage against diphtheria, pertussis (whooping cough), and tetanus is a good marker of the strength of a country\u2019s immunization programs since several administrations are required. All rich countries have vaccination coverage rates of more than 90%. It is in low- and middle-income countries where coverage is low \u2013 in some countries below 50%.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But the chart also shows that some poor countries \u2013 like Burundi, Rwanda, and Bangladesh \u2013 achieve high coverage rates. Similarly, countries in which a large share of the population is living in extreme poverty often \u2013 but not always \u2013 have lower immunization rates, as ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/vaccination-coverage-dpt-by-extreme-poverty?endpointsOnly=0", "children": [ { "text": "this chart shows", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/vaccination-coverage-by-income-in", "type": "chart", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Vaccines save lives", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "type": "text", "value": [ { "text": "We know that vaccines save lives. But how many lives vaccines have they saved? ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The World Health Organisation (WHO) suggests that vaccination prevents 2-3 million deaths each year.{ref} ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage", "children": [ { "text": "https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} However, while we are certain that vaccines have saved millions of lives, calculating a precise number is impossible. Also the quoted number from the WHO is in important ways a very low estimate.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The counterfactual world, in which vaccines would have never been developed, would be so different that an estimate of the impact of vaccines is impossible. One example that makes this clear is to consider the impact of the smallpox vaccine: ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/smallpox", "children": [ { "text": "Smallpox", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " was once an extremely common and deadly infectious disease, but it has been eradicated globally back in 1977 thanks to the vaccination against the disease. It is impossible to know exactly how many people would die of smallpox today if scientists had not developed the vaccine. Reasonable estimates are in the range of around 5 million lives per year, which implies that between 1980 and 2018 around 150 to 200 million lives have been saved.{ref}UNICEF (1996) and Hinman, A. R. (1998) estimate that in the absence of a vaccine the world would have seen 5 million deaths due to smallpox every year in the mid-1990s.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Assuming that the estimate for the mid-1990s provides a midpoint estimate for the period since 1980 and therefore multiplying the 5 million per year estimate by the number of years between 1980 and 2018 means that since the eradication of the disease 190 million people\u2019s lives were saved.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "UNICEF (1996) \u2013 Vaccines bring 7 diseases under control. Online\u00a0", "spanType": "span-simple-text" }, { "url": "https://www.unicef.org/pon96/hevaccin.htm", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref} This makes clear why it is so difficult to estimate the number of lives saved every year and why the WHO estimate is rather low.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "How vaccines work & herd immunity", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The basic mechanism by which vaccines work is simple: Vaccines create immunity in an individual by introducing a weakened or killed form of the pathogen that make us ill \u2013 such as bacteria or viruses \u2013 or its toxins or one of its surface proteins. The vaccine induces acquired immunity\u00a0so that when your body encounters the real disease-causing agent it is ready to mount a defense.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There is a collective social benefit in a high vaccination coverage. For most diseases, the greater the proportion of people who are immunized, the better protected is everyone in the population as the disease transmission can be reduced or stopped. Herd immunity is a community protection that is created when a high percentage of the population is vaccinated, such that it less likely that the infectious disease spreads.{ref}See Oxford's Vaccine Knowledge Project for an explanation here: ", "spanType": "span-simple-text" }, { "url": "http://vk.ovg.ox.ac.uk/herd-immunity", "children": [ { "text": "http://vk.ovg.ox.ac.uk/herd-immunity", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Herd immunity provides a protective barrier, especially also for those who ", "spanType": "span-simple-text" }, { "children": [ { "text": "cannot", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " be vaccinated. These include vulnerable groups such as babies too young to be vaccinated or immune-compromised children who are the first potential victims of low vaccination rates.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "When a person is immune to a disease they can act as a barrier to slow down or prevent the transmission of disease to other people. When the number of people in a population that are immune against a disease is reached, such that a disease no longer persists in the population, this is called the ", "spanType": "span-simple-text" }, { "children": [ { "text": "herd immunity threshold", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (HIT). The table shows the HIT for several diseases. Measles and pertussis are highly contagious airborne diseases and a larger share of people need to be vaccinated to stop the transmission. Because of this these diseases have the highest HIT rates that need to be reached. For example, two doses of measles vaccination offers 99% protection, while in the absence of immunization, the lifetime risk of infection is nearly 100%.{ref}Beutels P, Van Damme P, Van Casteren V, Gay NJ, De Schrijver K, Meheus A.\u00a0", "spanType": "span-simple-text" }, { "children": [ { "text": "The difficult quest for data on \"vanishing", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "\"", "spanType": "span-simple-text" }, { "children": [ { "text": "vaccine-preventable infections in Europe: the case of measles in Flanders", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "\u00a0(", "spanType": "span-simple-text" }, { "children": [ { "text": "Belgium", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "). Vaccine. 2002 Oct 4;20(29-", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "30):3551-9 ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/12297401", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Herd Immunity Thresholds of vaccine-preventable diseases{ref}This table is taken from ", "spanType": "span-simple-text" }, { "url": "https://en.wikipedia.org/wiki/Herd_immunity", "children": [ { "text": "Wikipedia's entry on Herd Immunity", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u00a0\u2013 the original sources are listed there.{/ref}", "spanType": "span-simple-text" } ], "type": "heading", "level": 5, "parseErrors": [] }, { "type": "html", "value": "<div class=\"raw-html-table__container\"><table><thead><tr><th scope=\"col\" colspan=\"1\">Disease</th><th scope=\"col\" colspan=\"1\">Transmission</th><th scope=\"col\" colspan=\"1\">Basic reproduction number</th><th scope=\"col\" colspan=\"1\">Herd Immunity Threshold</th></tr></thead><tbody><tr><td colspan=\"1\" rowspan=\"1\">Measles</td><td colspan=\"1\" rowspan=\"1\">Airborne</td><td colspan=\"1\" rowspan=\"1\">12\u201318</td><td colspan=\"1\" rowspan=\"1\">92\u201395%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Pertussis</td><td colspan=\"1\" rowspan=\"1\">Airborne droplet</td><td colspan=\"1\" rowspan=\"1\">12\u201317</td><td colspan=\"1\" rowspan=\"1\">92\u201394%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Diphtheria</td><td colspan=\"1\" rowspan=\"1\">Saliva</td><td colspan=\"1\" rowspan=\"1\">6\u20137</td><td colspan=\"1\" rowspan=\"1\">83\u201386%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Rubella</td><td colspan=\"1\" rowspan=\"1\">Airborne droplet</td><td colspan=\"1\" rowspan=\"1\">6\u20137</td><td colspan=\"1\" rowspan=\"1\">83\u201386%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Smallpox</td><td colspan=\"1\" rowspan=\"1\">Airborne droplet</td><td colspan=\"1\" rowspan=\"1\">5\u20137</td><td colspan=\"1\" rowspan=\"1\">80\u201386%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Polio</td><td colspan=\"1\" rowspan=\"1\">Fecal-oral route</td><td colspan=\"1\" rowspan=\"1\">5\u20137</td><td colspan=\"1\" rowspan=\"1\">80\u201386%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Mumps</td><td colspan=\"1\" rowspan=\"1\">Airborne droplet</td><td colspan=\"1\" rowspan=\"1\">4\u20137</td><td colspan=\"1\" rowspan=\"1\">75\u201386%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">SARS</td><td colspan=\"1\" rowspan=\"1\">Airborne droplet</td><td colspan=\"1\" rowspan=\"1\">2\u20135</td><td colspan=\"1\" rowspan=\"1\">50\u201380%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Ebola</td><td colspan=\"1\" rowspan=\"1\">Bodily fluids</td><td colspan=\"1\" rowspan=\"1\">1.5\u20132.5</td><td colspan=\"1\" rowspan=\"1\">33\u201360%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Influenza</td><td colspan=\"1\" rowspan=\"1\">Airborne droplet</td><td colspan=\"1\" rowspan=\"1\">1.5\u20131.8</td><td colspan=\"1\" rowspan=\"1\">33\u201344%</td></tr></tbody></table></div>", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Progress made with vaccination", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "type": "text", "value": [ { "text": "In total there are now at least 28 human diseases against which we have effective vaccines.{ref}Cholera, Dengue fever, Diphtheria, Haemophilus influenzae type b, Hepatitis A, Hepatitis B, Hepatitis E, Human papilloma-virus, Influenza, Japanese encephalitis, Malaria, Measles, Meningococcal disease, Mumps, Pneumococcal disease, Pertussis, Poliomyelitis, Rabies, Rotavirus gastroenteritis, Rubella, Tetanus, Tick-borne encephalitis, Tuberculosis, Typhoid fever, Varicella, Yellow fever, Shingles (Herpes Zoster), and Smallpox.", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "See ", "spanType": "span-simple-text" }, { "url": "https://en.wikipedia.org/wiki/Vaccine-preventable_diseases", "children": [ { "text": "https://en.wikipedia.org/wiki/Vaccine-preventable_diseases", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " and ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/", "children": [ { "text": "https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} The breakthrough that allowed us to get there was made in the late 18th century, the smallpox vaccine was the very first vaccine.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Smallpox and the origin of vaccination", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Vaccination has a long history. An early form of vaccination was referred to as 'variolation' or more broadly as 'inoculation'. Practised for a long time in Asia, this was an ancient technique of deliberate ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/smallpox", "children": [ { "text": "smallpox", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " infection in which dried\u00a0smallpox scabs were blown up the nose to infect the person with a form of the disease which was often milder. By the 1700s variolation had spread to Africa, India and the Ottoman Empire, followed by the UK and America, where the method of infection more frequently used was a puncture to the skin.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Variolation did work, but there were large risks. Those variolated could contract the more severe form of smallpox and die, and they could also transmit the disease to others.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In 1796 English physician Edward Jenner demonstrated another method of inoculation in which he relied on cowpox. Cowpox is a similar disease to smallpox and it had previously been observed that an infection with cowpox can protect against smallpox. Jenner conducted an experiment using matter from a cowpox lesion to inoculate his gardener\u2019s eight-year-old son James Phipps. Two months later Jenner exposed the boy to smallpox lesion matter\u00a0and when Phipps did not develop smallpox he concluded that he was protected against the disease. Jenner called the procedure \u2018vaccination\u2019 after 'vacca' the Latin word for cow because of the origin of this first vaccination from the cowpox virus.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Following the findings of Jenner as the first scientific attempt to control disease by vaccination, the smallpox vaccine went through many iterations, with the newer vaccines produced by modern cell culture techniques (passing the virus through cell culture makes the vaccine safer). By the middle of the 20th century confidence grew that smallpox could be the first disease that humankind might be able to eradicate. In 1967 the WHO launched a ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/csr/disease/smallpox/vaccines/en/", "children": [ { "text": "global eradication of smallpox program", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". Mass vaccination of over 80% of a country's population ensued but people who were nomadic or lived in politically unstable regions posed particular problems. A number of innovations came in the development of foot-powered injector called the ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/csr/disease/smallpox/vaccines/en/", "children": [ { "text": "\u201cped-o-jet\u201d and then the bifurcated needle", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", which was efficient and cost-effective to use.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In order to reach large sections of population, epidemiologist ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/csr/disease/smallpox/vaccines/en/", "children": [ { "text": "William Foege", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " developed Eradication Escalation (E2) to contain smallpox outbreaks during October (the seasonal low point of smallpox transmission where prevention of just few cases could stop a smallpox chain transmission). ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/csr/disease/smallpox/vaccines/en/", "children": [ { "text": "Other obstacles faced", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " included forcibly vaccinating an Indian religious leader to convince his followers to be vaccinated, negotiation of ceasefires for vaccine transport in war-torn Nigeria, vaccinating in concentric rings around an outbreak, and cash bounties to reward the reporting of smallpox cases. Finally in 1977 the last case of naturally contracted smallpox was reported in Somalia, in Ali Maow Maalin, and in 1980 the ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/csr/disease/smallpox/vaccines/en/", "children": [ { "text": "WHO announced that smallpox had been eradicated", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". We cover the history of smallpox, including the vaccination and eradication, in more detail in our entry on ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/smallpox", "children": [ { "text": "smallpox", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Vaccine innovation", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart here shows a timeline of innovation in the development of vaccines. Each bar begins in the year in which the pathogenic agent was first linked to the disease and the bar ends in the year in which a vaccination against that pathogen was licensed in the US.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "For some diseases there has been a relatively short timespan between when the infectious agent was linked to the disease and when a vaccine was developed. Before 2020 the quickest development was that for measles. The agent was linked to the disease in 1953 and the vaccine was licensed in the U.S. in 1963. In 2020 this record was broken when ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/covid-vaccinations", "children": [ { "text": "several vaccines", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " were developed within just one year to fight the ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/coronavirus", "children": [ { "text": "coronavirus pandemic", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "url": "https://ourworldindata.org/malaria/", "children": [ { "text": "Malaria", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " is proving harder as it has been over a century since the agent was linked to the disease.\u00a0Alphonse Laveran discovered in 1880 that the Plasmodium parasite is the cause for malaria.{ref}See Francis EG Cox (2010) \u2013 History of the discovery of the malaria parasites and their vectors. In ", "spanType": "span-simple-text" }, { "children": [ { "text": "Parasites and Vectors", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". Online ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2825508/#!po=8.33333", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Early vaccines developed in the last several decades were\u00a0insufficiently effective and until recently none of the scientific efforts led to a licensed vaccine. Recently there has been new hope for a malaria vaccine as we document in ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/malaria#a-vaccine-against-malaria", "children": [ { "text": "the relevant section in our entry on malaria", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Vaccine innovation has followed both scientific and political-economic developments:", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "list", "items": [ { "type": "text", "value": [ { "text": "Bacterial culture techniques which allowed the development of\u00a0bacterial vaccines for diphtheria, tetanus, and pertussis in the early 1900s.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The first and second world wars prompted combined efforts by universities, governments, and private companies.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "By the 1950s\u00a0viral tissue culture techniques allowed the development of vaccines against ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/polio", "children": [ { "text": "polio", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", measles, mumps, rubella, and varicella (chickenpox).", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "New technologies in molecular biology and advanced chemistry techniques\u00a0have most recently led to vaccines against hepatitis B, influenza, and pneumococcus, which causes pneumonia and meningococus, which causes meningitis and septicaemia.", "spanType": "span-simple-text" } ], "parseErrors": [] } ], "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "Vaccination-innovation-chart.png", "parseErrors": [] }, { "text": [ { "text": "Progress against vaccine-preventable diseases in the US", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The visualization here shows the reduction in cases and deaths from vaccine-preventable diseases in the United States after the introduction of each vaccine. This data was published by Roush and Murphy (2007){ref}Roush and Murphy (2007) \u2013 Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155\u20132163. ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/18000199", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} and the data can be viewed in a table ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/roush-and-murphy-2007-data/", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "For several diseases the US has achieved a 100% reduction of cases and deaths and for many other diseases the reduction is often very substantial as well.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Reduction of cases and deaths of vaccine-preventable diseases in the United States after the introduction of the vaccine.{ref}These data are taken from the research paper Roush and Murphy (2007) \u2013 Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155\u20132163 ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/18000199", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "\nThe vaccines against the diseases up till \u2018Tetanus\u2019 were vaccines licensed or recommended before 1980. The vaccines against the last 5 diseases were only licensed or recommended between 1980 and 2005.{/ref}", "spanType": "span-simple-text" } ], "type": "heading", "level": 5, "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "Vaccine_Reduction-of-Cases-and-Deaths.png", "parseErrors": [] }, { "text": [ { "text": "The development of the vaccine against measles and the history of measles in the US", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The introduction of a vaccine was not the only reason for progress against these diseases, as the visualization shows. The case-fatality rates of measles was falling in high income countries such as the US prior to the introduction of the vaccine in 1960 \u2013 this is best seen by switching from the linear to the logarithmic axis. Improved living conditions, nutrition, and medical advancements meant that contracting measles was less and less likely to be fatal.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The rate of cases however was virtually unchanged until after the measles vaccine was introduced \u2013 as our visualization shows.{ref}See also 'Graphical proof that vaccines work (with sources)' in ", "spanType": "span-simple-text" }, { "children": [ { "text": "Medium", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " online ", "spanType": "span-simple-text" }, { "url": "https://medium.com/@visualvaccines/graphic-proof-that-vaccines-work-with-sources-61c199429c8c", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "To account for such long-term changes, Roush and Murphy (2007) report data from the period shortly before the introduction of the respective vaccine. ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/18000199", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "A visualization showing the total number of cases and deaths can be seen ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/measles-cases-and-death", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/measles-cases-and-death-rate", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Global decline in vaccine-preventable diseases", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "The WHO estimates that ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "http://www.who.int/mediacentre/news/releases/2017/infants-worldwide-vaccinations/en/", "children": [ { "children": [ { "text": "2 to 3 million deaths", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": " are prevented every year through immunization against diphtheria, tetanus, whooping cough, and measles.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "text": "{ref}In our graphics and visualizations we rely on the ", "spanType": "span-simple-text" }, { "children": [ { "text": "Institute for Health Metrics", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (IHME) \u2018", "spanType": "span-simple-text" }, { "url": "http://ghdx.healthdata.org/gbd-results-tool", "children": [ { "text": "Global Burden of Disease Study 2016", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u2019 estimates of child death rates from individual VPDs (compared with other causes), TB death rates across countries, and death rates from individual VPDs; this dataset extends back to 1990 and therefore provides a longer-term perspective on these changes over time. However, lack of estimates from the IHME on the role of vaccination in the prevention of deaths means we rely on WHO data for the number of deaths prevented each year through vaccination and the total amount of deaths VPDs are responsible for.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The rates reported by the WHO and IHME are in a similar range but do differ slightly. WHO data on individual disease death rates can be found here: ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/gho/mortality_burden_disease/en/", "children": [ { "text": "http://www.who.int/gho/mortality_burden_disease/en/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Nonetheless, the WHO also estimates that VPDs are still responsible for ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "http://www.who.int/mediacentre/commentaries/vaccine-preventable-diseases/en/", "children": [ { "children": [ { "text": "1.5 million deaths", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": " each year. ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "In the chart we see the global number of deaths of children younger than 5 years per year from 1990 to 2017. The number of deaths which are wholly or partially preventable by vaccines are shown in color.{ref}Note that, as discussed later in this post, the role of vaccines in prevention varies between these causes of death. Measles, for example, has the capacity to be eliminated through vaccination. Diarrheal deaths, in contrast, cannot be eliminated through vaccination alone; hygiene, water services, and nutrition must also be prioritised.{/ref} The chart shows that the reductions in child deaths over this 25-year period were primarily achieved by a reduction of the number of deaths from vaccine-preventable diseases: The decline in causes which are not vaccine preventable has been modest, while the number of child deaths caused by diseases for which vaccines are available declined from 5.1 million deaths in 1990 to 1.8 million deaths 27 years later.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019.png", "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Two vaccines are responsible for saving millions each year: \u2018DTP\u2019 against diphtheria, tetanus, and pertussis (whooping cough) and \u2018MMR\u2019 against measles, mumps, and rubella.{ref}Some countries only give measles vaccines combined with rubella (MR) or with varicella in addition (MMRV).{/ref} Before the measles vaccine was introduced in 1963, measles caused a large number of deaths globally, estimated at ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "http://www.who.int/mediacentre/factsheets/fs286/en/", "children": [ { "children": [ { "text": "2.6 million each year", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": ". \u00a0Because about 86% of the ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "http://www.who.int/mediacentre/factsheets/fs378/en/", "children": [ { "children": [ { "text": "world population is immunized today,", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": " the number of people killed by measles have been cut dramatically to an estimated 95,000 deaths in 2017. Tetanus and pertussis were also previously much bigger killers, with pertussis affecting\u00a0especially children younger than 5 years and tetanus striking newborns (", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "http://www.who.int/immunization/diseases/tetanus/en/", "children": [ { "children": [ { "text": "killing an estimated 787,000 newborns", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": " in 1988, compared with 49,000 in 2013", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "children": [ { "text": ").", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "text": [ { "text": "The way ahead", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "However, the gains in global vaccination coverage have slowed down slightly in the last few years. The WHO estimates that\u00a0", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "http://www.who.int/mediacentre/factsheets/fs378/en/", "children": [ { "children": [ { "text": "19.5 million infants", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": " worldwide are still at risk of VPDs because they miss out on basic vaccines.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "text": "{ref}Highlighted are 10 countries ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/mediacentre/factsheets/fs378/en/", "children": [ { "text": "where approximately 60%", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " of these infants live in: Angola, Brazil, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan, and South Africa.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "In addition, all the recommended doses of a vaccine need to be received for it to be most effective. In the case of measles three vaccine doses are recommended. Even though an estimated ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "children": [ { "text": "85% of children receive their first dose of the vaccine, ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/mediacentre/factsheets/fs378/en/", "children": [ { "text": "this drops to 64%", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " for the second dose.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "children": [ { "text": "Therefore, it is not only lack of vaccination that is a problem, but it is under-vaccination that leads to deaths from VPDs.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "What then are the most deadly VPDs? Which diseases continue to kill the most people? ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "text": [ { "text": "The most deadly diseases", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Tuberculosis:", "spanType": "span-simple-text" } ], "spanType": "span-bold" }, { "children": [ { "text": " Determining which are the most deadly VPDs requires acknowledging that some vaccinations are more effective than others. While most vaccines included in national routine schedules are highly effective, a better vaccine for tuberculosis (TB) is desperately needed. It is Sub-Saharan Africa and parts of Asia in particular that ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/tuberculosis-death-rates", "children": [ { "text": "are affected by TB", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", as the world map shows.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "The vaccine for TB \u2013 Bacillus Calmette\u2013Gu\u00e9rin (BCG) \u2013 has been in use for nearly 100 years. It protects against severe forms of TB but is ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "https://wellcome.ac.uk/news/world-immunisation-week-seven-vaccine-challenges", "children": [ { "children": [ { "text": "not effective against pulmonary TB", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": " (in the lungs) and has variable effectiveness against TB in adults.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "text": "{ref}Zwerling A, Behr MA, Verma A, Brewer TF, Menzies D, Pai M. The BCG World Atlas: A Database of Global BCG Vaccination Policies and Practices. ", "spanType": "span-simple-text" }, { "children": [ { "text": "PLoS Medicine", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". 2011;8(3):e1001012. doi:10.1371/journal.pmed.1001012. Available ", "spanType": "span-simple-text" }, { "url": "http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001012", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" }, { "children": [ { "text": ",", "spanType": "span-simple-text" } ], "spanType": "span-superscript" }, { "text": "{ref}For a detailed commentary on why we do not yet have an effective TB vaccine see: Davenne T, McShane H. Why don\u2019t we have an effective tuberculosis vaccine yet?", "spanType": "span-simple-text" }, { "children": [ { "text": " Expert Review of Vaccines", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". 2016;15(8):1009-1013. doi:10.1586/14760584.2016.1170599. Available ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4950406/", "children": [ { "text": "here.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Furthermore, resistance of antibiotics used to treat TB is increasing, meaning some people can no longer be cured by drugs. The estimated number of people in 2016 with ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/features/qa/79/en/", "children": [ { "children": [ { "text": "multi-drug resistant TB was 490,000", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": ". ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "The fact that there is not a fully effective vaccine and that antibiotic treatment is facing serious difficulties makes TB the most deadly VPD.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Meningococcal meningitis and hepatitis B are also deadly VPDs. ", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Meningococcal Meningitis: ", "spanType": "span-simple-text" } ], "spanType": "span-bold" }, { "children": [ { "text": "Despite the introduction of ", "spanType": "span-simple-text" }, { "children": [ { "text": "MenAfriVac", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " in 2010, an effective vaccine against the most common type of meningitis in that region, meningococcal meningitis killed almost 130,000 people in 2016. Many cases occur in the so-called \u2018meningitis belt\u2019 of sub-Saharan Africa, crossing from Senegal to Ethiopia. Not all the countries in the meningitis belt have implemented mass vaccination campaigns for ", "spanType": "span-simple-text" }, { "children": [ { "text": "MenAfriVac", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " and also do not benefit from the expensive ", "spanType": "span-simple-text" }, { "children": [ { "text": "MenACWY", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " vaccine introduced into richer countries to protect against other types of meningococcal meningitis.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "text": "{ref}An affordable ", "spanType": "span-simple-text" }, { "children": [ { "text": "MenACWYX", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " vaccine is being developed to cover all the types of meningococcal disease (with the exception of meningitis B, which is available through a separate vaccine) and will also have the ability to be transported at higher temperatures. It is currently in phase 1 clinical trial, with the hope that it will be available for use in 2020\u20132022.{/ref}", "spanType": "span-simple-text" }, { "children": [ { "text": ",", "spanType": "span-simple-text" } ], "spanType": "span-superscript" }, { "text": "{ref}See Meningococcal disease in the Middle East and Africa: Findings and updates from the Global Meningococcal Initiative, Borrow, Ray et al. ", "spanType": "span-simple-text" }, { "children": [ { "text": "Journal of Infection", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", Volume 75 , Issue 1 , 1 - 11. Available ", "spanType": "span-simple-text" }, { "url": "http://www.journalofinfection.com/article/S0163-4453(17)30114-7/abstract", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Hepatitis B:", "spanType": "span-simple-text" } ], "spanType": "span-bold" }, { "children": [ { "text": " The vaccine against hepatitis B is also very effective (", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "url": "http://www.who.int/mediacentre/factsheets/fs141/en/", "children": [ { "children": [ { "text": "an estimated 95% effectiveness", "spanType": "span-simple-text" } ], "spanType": "span-fallback" } ], "spanType": "span-link" }, { "children": [ { "text": " in preventing disease), meaning increased vaccination could lead to a significant reduction in deaths. Still, global coverage of the hepatitis B vaccine is lagging. In 2015, while ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/mediacentre/factsheets/fs141/en/", "children": [ { "text": "84% coverage was reached", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " for the third dose of the vaccine, the coverage for the birth dose was only 39%. Estimates from mathematical models have shown that if infant coverage would reach 90%, and the first dose administered at birth, 84% of global hepatitis B-related deaths could be prevented.", "spanType": "span-simple-text" } ], "spanType": "span-fallback" }, { "text": "{ref}Susan T Goldstein, Fangjun Zhou, Stephen C Hadler, Beth P Bell, Eric E Mast, Harold S Margolis; A mathematical model to estimate global hepatitis B disease burden and vaccination impact, ", "spanType": "span-simple-text" }, { "children": [ { "text": "International Journal of Epidemiology", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", Volume 34, Issue 6, 1 December 2005, Pages 1329\u20131339, ", "spanType": "span-simple-text" }, { "url": "https://doi.org/10.1093/ije/dyi206", "children": [ { "text": "https://doi.org/10.1093/ije/dyi206", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". Available ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/16249217", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Eradication of diseases through vaccination", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Eradication is the ultimate goal of vaccination against a disease.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://owid.cloud/eradication-of-diseases", "type": "prominent-link", "title": "How do we eradicate diseases?", "description": "One of the greatest successes that we can imagine for humanity is the complete eradication of a disease. For one human disease \u2013 smallpox \u2013 this has actually\u00a0been achieved. The disease was fully eradicated in 1980. For other diseases we are getting close, as we show in our entry on the eradication of disease.", "parseErrors": [] }, { "text": [ { "text": "On the way to the eradication of polio", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Polio is targeted for global eradication. This has become possible through the polio vaccine that was developed in 1955. The WHO estimates that in 2015, ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/polio/#polio-prevalence-in-the-developing-world-and-the-global-spread-of-the-polio-vaccine", "children": [ { "text": "85% of infants around the world", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " received three doses of polio vaccine. And the number of paralytic polio cases have ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/polio/#the-number-of-reported-polio-cases-by-world-region", "children": [ { "text": "decreased by over 99%", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " since the 1980s, from an estimated 350,000 to 400,000 paralytic cases per year to ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/mediacentre/factsheets/fs114/en/", "children": [ { "text": "22 reported cases in 2017", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/polio/", "type": "prominent-link", "title": "Polio", "description": "We present the empirical evidence on the effort to eradicate poliomyelitis in an entry entirely dedicated to polio.", "parseErrors": [] }, { "text": [ { "text": "Eradication of smallpox", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "While the benefits might possibly be forgotten as vaccine-preventable diseases have lost their threat thanks to the introduction of the vaccines it is still true that people around the world \u2013 including those in richer countries \u2013 continue to benefit from vaccinations.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "One of the greatest successes of global health is eradication of smallpox. Smallpox, which just decades ago killed several hundred thousand people every year was successfully eradicated in 1980 thanks to the global vaccination program.{ref}Smallpox is the only disease that affects humans which has been eradicated through vaccination. Rinderpest, a disease that affected cattle, has also been eradicated. Polio is getting close to being eradicated.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://owid.cloud/smallpox", "type": "prominent-link", "title": "Smallpox", "description": "You find more detail about the disease and its eradication in our entry on smallpox.", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Public support and skepticism", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "People do not know how well we actually do in global vaccination", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Today vaccines protect millions of people around the world from infectious diseases.\u00a0In this fight we are much, much further ahead than most people realize.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The first chart shows the evidence for this misperception. In this chart we plotted the survey responses that people gave when they were asked ", "spanType": "span-simple-text" }, { "children": [ { "text": "\u201cHow many of the world\u2019s 1-year old children today have been vaccinated against some disease?\u201d", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". The correct answer was 85.8%; this is the share of 1-year olds that received the third dose of the combination vaccine that protects against Diphtheria, Tetanus, and Pertussis (whooping cough).", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But in all countries in which people were surveyed people were much too pessimistic about the global coverage. Americans think that only 35% of the world's children are vaccinated, the true coverage is 50 percentage points higher.{ref}This survey result is in line with the finding of the\u00a0", "spanType": "span-simple-text" }, { "children": [ { "text": "Gapminder Ignorance Project", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", which studied Americans'\u00a0perception of global vaccination efforts. Just as in the Ipsos Mori survey, the answers that most Americans gave were far off from the truth.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "Ignorance-Test_Global-Measles-vaccination-coverage.png", "parseErrors": [] }, { "type": "text", "value": [ { "text": "More information on the Gapminder 'Ignorance Test' can be found ", "spanType": "span-simple-text" }, { "url": "http://www.gapminder.org/ignorance/", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". The results for the US are ", "spanType": "span-simple-text" }, { "url": "http://www.gapminder.org/news/ignorance-survey-in-the-usa-2013/", "children": [ { "text": "here on Gapminder's site", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "\n{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In Japan people were even more pessimistic and thought that only 18% were vaccinated. As it is often the case in\u00a0questions on global development we again see that people in poorer countries have a ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/wrong-about-the-world", "children": [ { "text": "more accurate view of the world", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ": in Kenya and Senegal people thought that vaccines reach around two thirds of all children in the world, but even these highest estimates are 20 percentage points too low.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "We hugely underestimate global vaccination coverage{ref}", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "\nThe survey results are from\u00a0Chris Jackson (2017) \u2013 Global Perceptions of Development Progress: \u2018Perils of Perceptions\u2019 Research\u2019, published by Ipsos MORI, 18 September 2017. Online ", "spanType": "span-simple-text" }, { "url": "https://www.ipsos.com/en/global-perceptions-development-progress-perils-perceptions-research", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "type": "heading", "level": 5, "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "Misperception-of-global-vaccination-coverage.png", "parseErrors": [] }, { "text": [ { "text": "People\u2019s view on vaccination coverage is outdated by more than three decades", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart here illustrates how outdated people's answers are. Most individuals think that the global vaccination coverage today is as low as it was in the 1980s or even earlier.{ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Terminology: ", "spanType": "span-simple-text" }, { "children": [ { "text": "vaccination", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " and ", "spanType": "span-simple-text" }, { "children": [ { "text": "immunization", "spanType": "span-simple-text" } ], "spanType": "span-italic" } ], "spanType": "span-bold" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There is a technical difference between vaccination and immunization, as the National Health Service (NHS)\u00a0", "spanType": "span-simple-text" }, { "url": "http://www.shb.scot.nhs.uk/board/publichealth/immunisation.asp", "children": [ { "text": "explains", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ": \u201cVaccination means having a vaccine \u2013 that is actually getting the injection, or nasal spray or oral vaccine. Immunization means both receiving a vaccine and then becoming immune to a disease\u201d. The distinction is made because in a very small number of those who are vaccinated the vaccination will not \u2018take\u2019 and therefore that vaccinated person will not be immunized (i.e. will not be immune to the disease). However, as this refers to a very small number of people both terms are often used interchangeably across the academic literature and in media reporting and we follow this convention in this entry.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The World Health Organization recommends routine vaccinations to prevent illness, death and disability from diseases including diphtheria, pertussis (whooping cough), tetanus, polio, measles, and hepatitis B.{ref}For the WHO recommendations see\u00a0", "spanType": "span-simple-text" }, { "url": "http://www.who.int/ith/vaccines/en/", "children": [ { "text": "http://www.who.int/ith/vaccines/en/", "spanType": "span-simple-text" } ], "spanType": "span-link" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The Bacille Calmette-Guerin (BCG) vaccine for tuberculosis (TB) is recommended in countries where TB is common. BCG policies and practices have varied considerably across time and countries. The ", "spanType": "span-simple-text" }, { "url": "http://www.bcgatlas.org/", "children": [ { "text": "BCG World Atlas", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " is an online resource that tracks these changes comprehensively.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "We have created a ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds", "children": [ { "text": "chart", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u00a0that shows the absolute number of one-year-olds who have received the vaccinations.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Where the biggest gap in vaccination lies is with all children being fully vaccinated and protected as much as possible from infectious diseases. Gavi, the Vaccine Alliance, has analysis that suggests only ", "spanType": "span-simple-text" }, { "url": "https://www.nature.com/articles/d41586-017-05923-8", "children": [ { "text": "7% of infants in the 73 poorest countries are fully immunized\u00a0(that is, receiving all doses of all recommended vaccines)", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "How many people support vaccination across the world?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The London-based research charity ", "spanType": "span-simple-text" }, { "children": [ { "text": "The Wellcome Trust", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " published their ", "spanType": "span-simple-text" }, { "url": "https://wellcome.ac.uk/what-we-do/our-work/wellcome-global-monitor", "children": [ { "text": "Wellcome Global Monitor", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " in 2019 on attitudes to science and major health challenges. It is the world\u2019s largest study of its kind, surveying over 140,000 people from over 140 countries. As part of the ", "spanType": "span-simple-text" }, { "children": [ { "text": "Gallup World Poll", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", the 30-question survey ran during 2018.{ref}It provides data on topics such as trust in science and scientists; trust in sources of information about health; public understanding of the word \u2018science\u2019; the intersection between religious teachings and science; and attitudes to vaccines. In this post, we focus on how attitudes to vaccination vary across the world.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The Wellcome Trust survey asked three core questions related to attitudes to vaccines: do people think that vaccines are important for children to have; do they think vaccines are safe; and do they believe vaccines are effective.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Most people in the world think vaccines are important for children to have", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "More than 9-in-10 people in the world (92%) think that vaccines are important for children to have.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "How support varies across the world is shown in the map. We see high support for vaccination across almost all countries. In most countries over 80% of respondents think child vaccination is important, in many countries it is over 90% who think so.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There is a visible North-South divide in attitudes: support is highest across South Asia at 98%; 97% in South America; 94% in Northern Africa; and 92% in Southern Africa. Support is still high, but lower across North America (87%); Western Europe (83%) and Eastern Europe (80%).", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Of those surveyed in Venezuela, Palestine, Ethiopia and Northern Cyprus thought vaccines were most important: 100% were in favour.{ref}This is a stark result for Venezuela in particular (although perhaps unsurprising) since the availability and coverage of child vaccination ", "spanType": "span-simple-text" }, { "url": "https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1", "children": [ { "text": "has fallen significantly", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " over the last few years.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-agrees-vaccines-are-important-wellcome", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Most people in the world think vaccines are safe, but mistrust is high in some countries", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Some parents may not agree for children to be vaccinated if they think vaccines are unsafe or could potentially cause side-effects which are worse than the benefits. How prevalent are these safety concerns?", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Globally, a small share of people disagree that vaccines are safe. Only 7% of respondents across the world said they \u201cstrongly disagree\u201d or \u201csomewhat disagree\u201d with the statement \u2018Vaccines are safe\u2019.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In many countries these concerns are very low: in Bangladesh, for example, less than 1% disagree that vaccines are safe. In neighbouring India, only 2% disagree. We see this distribution across the world in the map.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Trust in vaccines is not high everywhere. There are some clear outliers. The French were most skeptical: 1-in-3 disagreed that vaccines were safe. Many in neighbouring Switzerland and Belgium were also very skeptical: more than 20% disagreed. Other countries with high mistrust of vaccine safety were Gabon (26%); Togo (25%); Russia (24%); Austria (21%), and Iceland (21%).", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-disagree-vaccines-are-safe-wellcome-trust", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Only 5% of respondents globally disagree that vaccines are effective but skepticism is much higher in some countries", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "In response to the statement \u2018Vaccines are effective\u2019, only 5% of respondents across all surveyed countries said they \u201cstrongly disagree\u201d or \u201csomewhat disagree\u201d. The vast majority of people do not think of vaccines as ineffective.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But, as with the other surveyed questions, this varies significantly across countries. We see this in the map. In some countries, very few respondents disagreed: less than 1% in Bangladesh and Egypt; 2% in India and Ethiopia; and 3% in China, Germany and the UK.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Liberia is most skeptical with 28% disagreeing that vaccines are effective. But skepticism was also high in France (18%); Namibia (16%); Nigeria (16%); and Peru (15%).", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-disagrees-vaccines-are-effective", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "In some countries many people are undecided on vaccination", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The finding of the Wellcome Trust of mostly very positive attitudes towards vaccines \u2013 a health intervention that ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/vaccination#how-is-the-world-doing-in-its-fight-against-vaccine-preventable-diseases", "children": [ { "text": "saves millions of lives", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " and ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/smallpox", "children": [ { "text": "eradicated one of the worst diseases", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " humanity ever faced \u2013 is a very positive finding.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But there is a concerning finding which is hidden when we look only at agreement and disagreement to the questions in the Global Monitor.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Take Japan as one example. Only 66% of Japanese respondents thought vaccines were important for children to have \u2013 very low in comparison to other countries. But few disagreed that vaccines were safe (only 8%) and disagreed that they\u2019re effective (only 3%). If few people thought they were unsafe and ineffective, why would support for vaccines be so low?", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Many Japanese respondents did not answer either way. 28% answered \u201cneither agree nor disagree\u201d to ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-neither-agrees-disagrees-vaccines-important", "children": [ { "text": "whether child vaccination is important", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "; 55% to the question regarding the ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-neither-agree-disagree-vaccines-are-safe", "children": [ { "text": "safety of vaccines", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "; and one-third were undecided on their effectiveness. It's difficult here, without further questions, to fully interpret the opinions of those in this undecided category: maybe they had no opinion; or they thought vaccines could be safe or effective in some cases, but not all; or some vaccines were safe but others were not. With this data, it's impossible to fully understand their reasoning.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "This stance was common across several other countries, as we see in the map.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-neither-agrees-nor-disagrees-vaccines-effective", "type": "chart", "parseErrors": [] }, { "type": "text", "value": [ { "text": "While being undecided or divided is perhaps less concerning than denialism on the importance, safety and effectiveness of vaccination, it nonetheless suggests that many are unaware of the massive role vaccines have played in ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/vaccination#eradication-of-diseases-through-vaccination", "children": [ { "text": "eradicating diseases", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", and ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/vaccination#diseases-preventable-through-vaccination", "children": [ { "text": "saving lives across the world", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". The success story of vaccines is one we don\u2019t tell often enough.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "It\u2019s also true that people in the 'neither' group may be more likely to be convinced by arguments that are put forward by those who deny the safety, effectiveness and importance of vaccination.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In a ", "spanType": "span-simple-text" }, { "url": "http://ourworldindata.org/vaccine-skepticism", "children": [ { "children": [ { "text": "related post", "spanType": "span-simple-text" } ], "spanType": "span-bold" } ], "spanType": "span-link" }, { "text": "\u00a0we take a look at why denialism around vaccination exists, and what is effective in addressing it.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Does vaccine skepticism affect immunization coverage?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The crucial question to ask when considering the importance of vaccine skepticism is: does it actually have an effect on behaviour? Does it really affect the share of children who are vaccinated?", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the chart we see the comparison of vaccination rates \u2013 here as the share of children who were immunized against diphtheria, pertussis and tetanus (DTP) in 2015, the latest year available \u2013 to the share of respondents in a given country who disagreed that vaccines are safe.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "You can also ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/immunization-measles-vs-vaccine-safety", "children": [ { "text": "see this relationship", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " for measles vaccine coverage.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Overall we see that widespread public concern for vaccine safety does not appear to be strongly correlated with vaccination rates. While one-third of the French public disagrees with their safety, 97% of children in France are vaccinated.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are numerous other reasons, however, why vaccination rates in some countries are low: in low-to-middle income countries the availability, affordability and access to vaccines can be poor. Having low coverage rates often doesn\u2019t reflect the population\u2019s view of them. As the chart shows, in many poor countries the situation is the opposite as in France: the vast majority of the population considers vaccine safe, but only about every second child receives the DTP vaccine.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "One country which stands out is Ukraine: there we see that vaccination rates are uncharacteristically low for ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/gdp-per-capita-worldbank", "children": [ { "text": "its income level", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2013 less than 1-in-4 children receive the DTP vaccine. Skepticism of vaccine safety in Ukraine is high at 15%.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Is there evidence that skepticism is reflected in cases and deaths from vaccine-preventable diseases? Over the last few years there has been ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/csr/don/06-may-2019-measles-euro/en/", "children": [ { "text": "a reported rise", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " in the number of measles cases in countries which had previously been close to eliminating the disease. In Europe, for example, there were more than ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/csr/don/06-may-2019-measles-euro/en/", "children": [ { "text": "34,000 cases of measles", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " in the first two months of 2019 alone. Ukraine ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/csr/don/06-may-2019-measles-euro/en/", "children": [ { "text": "accounted for the majority", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " (more than 70%) of these cases. And here as well as in Albania and Romania some measles cases led to the death of children.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/perception-of-the-safety-of-vaccines-vs-vaccine-coverage", "type": "chart", "parseErrors": [] }, { "type": "text", "value": [ { "text": "The visualization shows the relationship between the share of people who trust doctors and nurses in their country and share who disagree that vaccines are safe. Overall we see that countries with higher levels of distrust in the safety of vaccines tend to also have less trust in health professionals.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are however some outliers: France has relatively high trust in health staff, but are most mistrusting of vaccine safety.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Health officials are worried that skepticism of vaccination will begin to translate to lower vaccination rates. One reason being attributed to higher skepticism is the spread of misinformation on social media.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Social media firms do have a responsibility for dealing with misinformation and need to consider how to react carefully. Currently, social and online media companies are being asked by politicians in the US and UK to ban or control anti-vaccination messaging. Banning or strict control could reduce the exposure to such messages but does not solve the root problem: the public are asking questions about vaccines and are looking to find answers online. A worry is that banning certain sorts of information and groups will fuel suspicion and only drive activity elsewhere.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Nonetheless, demands on social media firms to act is increasing. A request for action by ", "spanType": "span-simple-text" }, { "url": "https://schiff.house.gov/news/press-releases/schiff-sends-letter-to-google-facebook-regarding-anti-vaccine-misinformation", "children": [ { "text": "Adam Schiff to the CEOs of Google and Facebook", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " sparked a cascade of responses. In an open letter, he asked for action against vaccine misinformation and similar demands have been made since, from the UK Health Secretary Matt Hancock among others.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/trust-healthcare-vs-vaccine-safety", "type": "chart", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Vaccine policy", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "What determines if vaccinations are compulsory?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Countries vary in whether vaccination is compulsory, mandatory (required according to specific mandates), or voluntary. Navin and Largent (2017) provide a helpful distinction between these policies. A compulsory policy is when refusing vaccination is illegal, while mandatory vaccination when certain goods and services are limited for not vaccinating.{ref}Navin M. Largent, improving non-medical exemption vaccine policies: three case studies. Public Health Ethics. 2017; 10: 225\u2013234. Available ", "spanType": "span-simple-text" }, { "url": "https://philpapers.org/rec/NAVINV", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Which policy is followed has depended much on historical legacy, which becomes clear when one considers some of the different regulations and their history around the world:", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Compulsory vaccination:", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " Many Eastern Bloc countries introduced compulsory vaccination during the communist era. Vaccination was previously compulsory in Romania for example and after a drop in vaccination rates the country is going through the process of reintroducing compulsory vaccination. The same is true for Italy and also France, which had compulsory vaccination for three diseases but increased this number to 11 in January 2018 in response to a drop in vaccination rates.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Mandatory vaccination:", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " Some countries, such as the United States, have mandates for vaccination where a child is required to be vaccinated to enter state school or daycare. An early case in the US paved the way for state jurisdiction to protect public health in light of personal liberty.{ref}See: ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/", "children": [ { "text": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} In Jacobson v. Massachusetts (1905) the Supreme Court ruled that states have the authority to require vaccination against smallpox during a smallpox epidemic. Since then the US has had a history of school vaccination requirements. The increased number of children in public schools as a result of the compulsory school attendance law led to an increased risk of smallpox outbreaks, through close contact in large crowded classrooms.{ref}Stern, M., Alexandra. (2010). Better Off in School: School Medical Inspection as a Public Health Strategy During the 1918-1919 Influenza Pandemic in the United States{/ref} Similarly in Australia two policies penalize parents for not vaccinating their children. The 'No jab no play' policy removed unvaccinated children from state-sponsored childcare. The 2016 'No jab no pay' policy removes state welfare by not providing the universal 'Family Allowance' welfare payments for parents who are conscientious objectors of vaccination.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Voluntary vaccination:", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " Some countries where vaccination is voluntary had early pushback against vaccination, as in the UK and the Netherlands. In 1853 a law was passed in England and Wales requiring universal vaccination against smallpox, but opposition from anti-vaccinationists led to laws being passed to allow for conscientious objection.{ref}Amin, A.N.E., Parra, M.T., Kim-Farley, R. et al. (2012) \u2013 Ethical Issues Concerning Vaccination Requirements. In\u00a0", "spanType": "span-simple-text" }, { "children": [ { "text": "Public Health Reviews", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (2012) 34: 14. ", "spanType": "span-simple-text" }, { "url": "https://doi.org/10.1007/BF03391666", "children": [ { "text": "https://doi.org/10.1007/BF03391666", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". Online here: ", "spanType": "span-simple-text" }, { "url": "https://link.springer.com/article/10.1007/BF03391666", "children": [ { "text": "https://link.springer.com/article/10.1007/BF03391666", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Vaccination requirements for country entry:", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " For countries in Africa and South America where yellow fever is endemic or where the mosquito vector is present a certificate of proof of vaccination is required. Only then will the country issue a visa upon entry to that country to prevent importation of this disease (particularly if travellers come from, or have visited other yellow fever endemic areas).{ref}See: ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/csr/ihr/icvp/en/index.html", "children": [ { "text": "http://www.who.int/csr/ihr/icvp/en/index.html", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} In past centuries (17th to 19th), yellow fever was transported to North America and Europe, causing large outbreaks that disrupted economies and development, and in some cases decimated populations. Throughout the 18th and 19th century, yellow fever was among the most feared diseases in the ports of the Old and New World. Saudi Arabia is the only country that requires the ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/ith/updates/20170408/en/", "children": [ { "text": "additional vaccinations of meningococcal disease and polio", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " for pilgrims visiting Mecca.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Does it work to make vaccinations compulsory?", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Whether compulsory vaccination results in improved vaccination rates is not a straightforward question to tackle because it is highly dependant on country context, historical circumstance, cultural and social norms, as well as the practicalities of implementing and enforcing such a law. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Certainly in ", "spanType": "span-simple-text" }, { "url": "https://theconversation.com/despite-scepticism-europe-has-high-vaccination-rates-but-it-shouldnt-be-complacent-75169", "children": [ { "text": "Eastern Bloc countries", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " when the vaccination law was compulsory, vaccination rates have been high but it is unclear whether to attribute this to the law or the behaviours and mechanisms of compliance under communist rule. Certain vaccinations have historically been compulsory such as smallpox, polio, and yellow fever. Here vaccination rates have also been high but it also encouraged organised opposition to vaccination and public discontent. This is a major concern for public health authorities that a relationship of trust, between governments and citizens is threatened (particularly for health where a rhetoric of self-responsibility, personalisation, and choice is encouraged). ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are countries with high vaccination rates without compulsory vaccination and governments do not want to disrupt public trust and self-responsibility by making vaccination compulsory, particularly if it is not seen as needed. It has been argued that high coverage has been achieved through \"other approaches or efforts\" and so acceptance of compulsory vaccination might be problematic in countries such as Sweden, Norway, Denmark, the Netherlands, and the UK.{ref}Salmon, Daniel A et al., Compulsory vaccination and conscientious or philosophical exemptions: past, present, and future, The Lancet, Volume 367, Issue 9508, 436 - 442{/ref} ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In recent years governments have acted in response to epidemics to make vaccinations compulsory, as we have seen for 2017-18 with compulsory vaccinations in France, Italy, Germany, and Romania.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "One country where we can see the effect of variation in vaccination policy is the US. In the US states decide what vaccine exemptions are permitted for children who receive education in schools or use daycare. Public schooling unfortunately means that schools are sites of epidemics for childhood diseases, which is the reason such vaccination laws are required.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In individual states exemptions are granted for medical reasons but many states also allow for philosophical, personal belief or religious exemptions. Only three states \u2013 Mississippi, West Virginia, and California \u2013 only allow for medical exemption. ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/app/uploads/2017/11/Screen-Shot-2017-11-10-at-15.31.35.png", "children": [ { "text": "Californian immunization rates have increased", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " following a new Senate Bill SB 277 in 2015 to remove non-medical exemptions to vaccination. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart here shows vaccination coverage and what exemptions are allowed for each state. Fewer exemptions generally mean higher vaccine coverage. Indeed, Mississippi does often top the list as having the highest vaccination rates because only medical exemptions are allowed in the state. But starkly, Mississippi residents are also consistently the ", "spanType": "span-simple-text" }, { "url": "http://www.businessinsider.de/unhealthiest-states-in-the-us-health-rankings-2017-12?r=US&IR=T", "children": [ { "text": "unhealthiest", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " and ", "spanType": "span-simple-text" }, { "url": "https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/", "children": [ { "text": "poorest", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " in the entire country. Health outcomes are very poor and many residents cannot afford healthcare (", "spanType": "span-simple-text" }, { "url": "https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/", "children": [ { "text": "the state has the highest percentage without health insurance in 2017", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "). So perhaps it is unsurprising that residents accept subsidized vaccinations that are required for access to childcare and state schools.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Vaccination coverage of children, by US state in 2016/17{ref}The data source for vaccination coverage: School Vaccination Assessment Report, 2016-17 school year.", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": " Estimated vaccination coverage with 5 doses of Childhood Diphtheria toxoid, Tetanus toxoid, acellular Pertussis (DTaP) vaccination for kindergartners (typical age range is 4\u20136 years).", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "spanType": "span-newline" }, { "text": "The data source for exemptions is: Immunization Action Coalition, \"Exemptions Permitted for State Immunization Requirements,\" 2017; LexisNexis; StateNet 2017", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "spanType": "span-newline" }, { "text": "Regarding the school vaccination coverage and exemption methods the source notes: \"Each school year, school nurses, other school personnel, or health department personnel check the vaccination and exemption status of kindergartners enrolled in public and private schools as required by state law or regulation. State and local immunization programs measure vaccination coverage among children entering kindergarten annually. This may be done for every student or for a sample of students.", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "spanType": "span-newline" }, { "text": "State and local areas set the vaccination requirements. Immunization information systems (IISs) may be used as one source of data for school vaccination assessment. The school-level data are reported to the health department. The aggregate data are reported to CDC for public and private schools. Data for home-schooled students are not routinely reported to CDC.\"", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "spanType": "span-newline" }, { "text": "The types of permitted exemptions vary by state. For specific details refer to ", "spanType": "span-simple-text" }, { "url": "https://www.cdc.gov/vaccines/imz-managers/coverage/schoolvaxview/requirements/index.html", "children": [ { "text": "School Vaccination Requirements and Exemptions", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "type": "heading", "level": 5, "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "DTP-Vaccination-rate-by-US-State-and-exemption-status-1.png", "parseErrors": [] }, { "text": [ { "text": "Vaccine supply", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Supply constraints have caused problems for country access to vaccination. One-third of 194 countries have run out of a vaccine for a month or longer \u2013 according to ", "spanType": "span-simple-text" }, { "url": "http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health", "children": [ { "text": "data", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u00a0submitted to WHO and UNICEF \u2013\u00a0and this includes both high- and low-income countries. In the US, the Centers for Disease Control and Prevention (CDC) ", "spanType": "span-simple-text" }, { "url": "https://www.cdc.gov/vaccines/hcp/clinical-resources/shortages.html", "children": [ { "text": "stated", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " that reasons for shortages were multi-factoral and included\u00a0\"...companies leaving the vaccine market, manufacturing or production problems, and insufficient stockpiles\". In 2018, it ", "spanType": "span-simple-text" }, { "url": "http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health", "children": [ { "text": "was reported", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u00a0that shortages where supplies of vaccines were critically low included those that target yellow fever, hepatitis B, cholera, meningitis C, diphtheria, whooping cough, tetanus, hepatitis A, and tuberculosis.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Concerns about the supply of vaccines in an epidemic or pandemic have been raised. For example, the supply of yellow fever vaccine was limited for the outbreak in Angola in 2016 leading to the recommendation of a fractional dose to extend existing supplies.{ref}See the WHO ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/emergencies/yellow-fever/mediacentre/qa/en/", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "url": "http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health", "children": [ { "text": "Laurie Garrett argues", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " that because the drug had become so cheap (60 cents for each vaccine 2008) few companies had an incentive to produce it and world stocks of the vaccine were nearing zero, forcing the WHO to dilute donated vaccines from countries like Brazil (which sent 18 million doses) by 5 to 1 with the hope they would still be sufficiently effective. Romania experienced a situation of parallel vaccine exports in 2016 where more vaccines were exported than was supplied to meet the country's needs. A shortage of the\u00a0measles, mumps, and rubella (MMR) vaccine was partly responsible for the measles outbreak in 2016-17.{ref}See ", "spanType": "span-simple-text" }, { "url": "https://www.euractiv.com/section/health-consumers/news/romania-cuts-vaccine-exports-as-measles-outbreak-takes-hold/", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In Venezuela, a country experiencing an economic crisis, there are severe ", "spanType": "span-simple-text" }, { "url": "https://www.bbc.co.uk/news/resources/idt-sh/Venezuela_bridge", "children": [ { "text": "shortages of medicines, including vaccines", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", which has led to an ", "spanType": "span-simple-text" }, { "url": "https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1", "children": [ { "text": "estimated one million", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " unvaccinated children and the re-emergence of diseases such as diphtheria and measles.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "The cost of vaccines", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are five big pharmaceutical companies{ref}According to MacKenzie, D.\u00a0(2011) \u2013 Vaccines enjoy a healthy return. ", "spanType": "span-simple-text" }, { "children": [ { "text": "New Scientist", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". Available ", "spanType": "span-simple-text" }, { "url": "https://www.newscientist.com/article/dn20877-vaccines-enjoy-a-healthy-return/", "children": [ { "text": "online", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}\u00a0that account for 80% of vaccine production: Sanofi Pasteur, GlaxoSmithKline, Merck, Pfizer, and Novartis.{ref}In 2014 their vaccine business was acquired by GlaxoSmithKline, as reported ", "spanType": "span-simple-text" }, { "url": "https://www.telegraph.co.uk/finance/newsbysector/pharmaceuticalsandchemicals/11444023/GSK-and-Novartis-complete-deals-to-reshape-both-drugmakers.html", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Many vaccines are only provided by one or two suppliers. For newer vaccines there are often particularly few suppliers due to the high investment needed to develop a vaccine.{ref}There are exceptions however. A vaccine for tetanus and diphtheria (td) for example, has a large number of suppliers (13, and 7 for the paediatric formulation).{/ref} As one would expect from competition, the WHO reports that when vaccines are produced by a greater number of suppliers it leads to a decline of the prices of those vaccines.{ref}Review of vaccine price data. Submitted by WHO European Region Member States through the WHO/UNICEF.\u00a0Joint Reporting Form for 2013. Online ", "spanType": "span-simple-text" }, { "url": "http://www.euro.who.int/__data/assets/pdf_file/0009/284832/Review-vaccine-price-data.pdf?ua=1", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the past vaccines were often viewed as less profitable products for pharmaceutical companies, which led to a lack of investment and some companies pulling out of production altogether.{ref}The Economist. (2010). A smarter jab. Available ", "spanType": "span-simple-text" }, { "url": "http://www.economist.com/node/17258858#print", "children": [ { "text": "online", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But this has changed as the revenue of the global vaccines market has increased and richer country governments and insurance companies have been willing to pay more for new vaccines.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In addition, growing economies such as India and China are investing more in vaccines as well as developing their domestic manufacturing capacity. Poorer countries now have Gavi to help governments pool resources and make advance purchase commitments.{ref}The Economist. (2010). A smarter jab. Available ", "spanType": "span-simple-text" }, { "url": "http://www.economist.com/node/17258858#print", "children": [ { "text": "online", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Gavi is an international organisation created in 2000 to bring together public and private sectors, with the goal of equal access to new and underused vaccines for children in poorer countries. It subsidizes vaccines that otherwise would not be affordable for low-income countries. In addition to subsidizing vaccines themselves, Gavi offers ", "spanType": "span-simple-text" }, { "url": "https://www.gavi.org/about/programme-policies/health-system-and-immunisation-strengthening-support-framework/", "children": [ { "text": "vaccine introduction grants", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", which help to cover the costs of introduction of new vaccines into routine immunization schedules. The map here shows which countries are eligible for GAVI support. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/gavi-supported-countries", "type": "chart", "parseErrors": [] }, { "type": "text", "value": [ { "text": "Some vaccines still remain expensive. For example, the pertussis vaccine is available in two versions: whole cell (wP) containing the whole pertussis bacterium or acellular (aP) which contains a part of the pertussis bacterium. The pertussis vaccine is often combined with diphtheria and tetanus to produce either a DTwP or DTaP vaccine.{ref}See WHO guidance for more information at: ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf", "children": [ { "text": "https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "spanType": "span-newline" } ], "spanType": "span-fallback" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "DTaP is slightly more expensive; it is sometimes called 'the painless vaccine' because it causes less of a local reaction and pain but should not be given to children over the age of seven. However, DTwP has been shown to be more efficacious at preventing the transmission and spread of disease to unvaccinated people and to those with weak immunity.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "New vaccines tend to be more expensive as they are under patent protection. For example when the HepB vaccine was developed many lower income countries could not afford to pay $30 per dose.{ref}Jaffe, A. B., Lerner, J., Stern, S., & National Bureau of Economic Research. Innovation Policy and the Economy Group. (2006). ", "spanType": "span-simple-text" }, { "children": [ { "text": "Innovation policy and the economy", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". MIT Press. ", "spanType": "span-simple-text" }, { "url": "https://books.google.co.uk/books/about/Innovation_Policy_and_the_Economy.html?id=9I7KowFvI9oC&source=kp_cover&redir_esc=y", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Today there is often a differentiation between the prices paid by countries as shown in the small table.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Price differences for vaccines between the US and developing countries{ref}The source of the data is the ", "spanType": "span-simple-text" }, { "url": "http://mshpriceguide.org/en/home/", "children": [ { "text": "International drug price indicator guide", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "type": "heading", "level": 5, "parseErrors": [] }, { "type": "html", "value": "<div class=\"raw-html-table__container\"><table class=\"\"><tbody><tr><td><strong>Vaccine</strong></td><td><strong>Cost per dose in a developing country</strong></td><td><strong>Cost per dose in the US</strong></td></tr><tr><td>HepB</td><td>$0.58 - 13.20</td><td>$50 - 100</td></tr><tr><td>BCG</td><td>$0.16 - 1.11</td><td>$100 - 200</td></tr><tr><td>Yellow fever</td><td>$4.30 - 21.30</td><td>$50 - 100</td></tr></tbody></table></div>", "parseErrors": [] }, { "text": [ { "text": "Which countries include vaccines in their immunization schedules?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Several vaccines, including rubella, mumps, and rotavirus, are included in immunization schedules in many countries around the world. This means these vaccines are provided and recommended through routine services.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "This doesn't necessarily tell us how many children ", "spanType": "span-simple-text" }, { "children": [ { "text": "receive", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " these vaccines in each country. The vaccines may or may not be mandatory and their coverage rates may vary widely. Similarly, when countries do not have a vaccine in their schedule, this does not mean that the vaccine is completely unavailable in those countries, as it may be optional or available commercially.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the chart you can see which countries include rubella vaccines in their national immunization schedules. Rubella vaccines became available for the first time in 1969, starting in the United States, where it was developed.{ref}Lanziera, T., Haber, P., Icenogle, J. P., & Patel, M. (n.d.). Rubella. In ", "spanType": "span-simple-text" }, { "children": [ { "text": "Epidemiology and Prevention of Vaccine-Preventable Diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". Communication and Education Branch, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention.", "spanType": "span-simple-text" }, { "url": "https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html", "children": [ { "text": " https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} It was included in the schedules of the United States and most European countries as early as 1994 (the first year of this dataset). Over time, more countries included it in their schedule.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But this took many years for some countries: for example, it took until 2018 for it to be included in countries such as Uganda and Congo.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "As of 2021 some countries, such as Nigeria and South Africa, still do not include it in their schedules.{ref}World Health Organization. (2021). ", "spanType": "span-simple-text" }, { "children": [ { "text": "New and underutilized vaccines introduction", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".", "spanType": "span-simple-text" }, { "url": "https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html", "children": [ { "text": " https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the links below, you can see these charts for other vaccines.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/rubella-vaccine-immunization-schedule", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Why do vaccine schedules differ?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "text": [ { "text": "The chickenpox example", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Chickenpox\u00a0(varicella) is an example of a vaccine that some countries adopt into their routine childhood vaccination schedules, while others do not. The question that follows is why there is a difference in opinion for introducing widespread uptake of a vaccine or not. Japan was one of the first countries to adopt universal chickenpox vaccination.{ref}Bonanni et al. 2009; Bonanni P., Breuer J., Gershon A., Gershon M., Hryniewicz W., Papaevangelou V., et al. (2009) \u2013 Varicella vaccination in Europe - taking the practical approach. BMC Med 7: 26 ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/19476611", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Australia, Canada, Germany, Qatar, Republic of Korea, Saudi Arabia, Taiwan, Uruguay, U.S., Italy (Sicily only) and Spain (Madrid only) followed afterwards and adopted universal chickenpox vaccination. When extreme cases of chickenpox have occurred there have been calls for the vaccine to become ", "spanType": "span-simple-text" }, { "url": "http://www.bbc.co.uk/news/uk-england-cambridgeshire-36952432", "children": [ { "text": "available for free", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " through the National Health Service in the UK. However, most European countries do not vaccinate against chickenpox, except for 'at risk' groups. The main reason for not adopting universal vaccination is the high cost. Additional supporting justifications are that it is usually a ", "spanType": "span-simple-text" }, { "url": "http://www.nhs.uk/chq/Pages/1032.aspx?CategoryID=62", "children": [ { "text": "mild disease", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " and the\u00a0benefit of fewer cases of shingles \u2013 as explained ", "spanType": "span-simple-text" }, { "url": "https://theconversation.com/everything-you-need-to-know-about-chickenpox-and-why-more-countries-dont-use-the-vaccine-63473", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The Centers for Disease Control and Prevention in the US ran\u00a0the ", "spanType": "span-simple-text" }, { "url": "https://www.cdc.gov/chickenpox/surveillance/vasp.html", "children": [ { "text": "Varicella Active Surveillance Project", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " (VASP)\u00a0from 1995 through to 2010 to monitor the\u00a0impact of the varicella vaccination program and the key finding is shown in the chart. The coverage of the vaccine in\u00a0Los Angeles County rose from 37.9% in 1997 to 95.1% in 2010, and in Philadelphia from 41.2% in 1997 to 94.6% in 2010\u00a0(one-dose vaccinations for children between 19 and 35 months of age). By 2010, varicella incidence declined by 98% in Antelope Valley (California) and West Philadelphia (Pennsylvania) compared with 1995. Outbreaks and hospitalizations also decreased rapidly. From 1995 to 1998, hospitalization rates ranged from 2.2 to 3.3 per 100,000 population but by 2006-2010 this had declined to 0.2 per 100,000 in Antelope Valley and 0.5 per 100,000 in Philadelphia.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Chickenpox is an example that can also help to answer the question of whether better hygiene or vaccination are in fact responsible for the reduced rates of disease. Although both are important, a more recently adopted vaccination such as chickenpox can demonstrate the effects of vaccination in reducing the rate of disease after the importance of hygiene was discovered and became a preventative measure against disease. As hygiene standards already reached high levels, the additional benefit of the vaccine is confirmed. The impact on disease rates demonstrate it is not hygiene but vaccination that reduced the incidence of chickenpox so dramatically in the US.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "Chickenpox-cases-in-US.png", "parseErrors": [] }, { "text": [ { "text": "Which countries have mandatory childhood vaccination policies?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "With the widespread rollout of ", "spanType": "span-simple-text" }, { "url": "http://ourworldindata.org/covid-vaccinations", "children": [ { "text": "COVID-19 vaccines", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " globally, some countries have started to consider mandatory vaccination, although no country has yet to make vaccines mandatory for its population.{ref}Gostin, L. O., Salmon, D. A. and Larson, H. J. (2021) \u2018Mandating COVID-19 Vaccines\u2019, ", "spanType": "span-simple-text" }, { "children": [ { "text": "JAMA", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". American Medical Association, 325(6), p. 532. doi: 10.1001/jama.2020.26553.{/ref} While COVID-19 has resurfaced the debate on vaccination policies, it has been an important topic for many other diseases. The World Health Organization (WHO) estimates that vaccines save two to three million lives each year (excluding COVID). The development of vaccines against vaccine-preventable childhood diseases has been a key driver in the decline of ", "spanType": "span-simple-text" }, { "url": "http://ourworldindata.org/child-mortality", "children": [ { "text": "child mortality", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Despite it being such an important topic, it is surprising that information about which countries have mandatory vaccine policy is lacking, and it is childhood vaccines under a country\u2019s national immunization schedules that are most commonly made mandatory.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In this article we present a new global dataset which looks at childhood vaccination policies across the world.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "How do childhood vaccination policies vary across the world?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "We recently charted mandatory childhood vaccine policies worldwide as they are becoming an increasingly important policy intervention for governments trying to address low vaccination rates.{ref}Vanderslott, S., & Marks, T. (2021). ", "spanType": "span-simple-text" }, { "url": "https://www.sciencedirect.com/science/article/pii/S0264410X21005478", "children": [ { "text": "Charting mandatory vaccination policies worldwide", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Vaccine", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The term \u2018mandatory\u2019 and \u2018mandates\u2019 are taken to mean quite different things across countries. Whilst the term is commonly used it is poorly defined.{ref}Attwell, K. and C. Navin, M. (2019) \u2018Childhood Vaccination Mandates: Scope, Sanctions, Severity, Selectivity, and Salience\u2019, ", "spanType": "span-simple-text" }, { "children": [ { "text": "The Milbank Quarterly", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", 97(4), pp. 978\u20131014. doi: 10.1111/1468-0009.12417.{/ref} Mandates require vaccination for a certain purpose, most commonly related to school entry for children. While definitional disagreements still persist, it remains important to better understand what policies are in place across countries and the reasons driving changes in policy over time.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Our list indicates whether a country has a mandatory vaccination policy for one or more vaccine and the strictness of the mandate on a scale ranging across three levels: mandatory, mandatory for school entry, or recommended. The childhood vaccines include the vaccines that protect from ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide", "children": [ { "text": "measles,", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " mumps, rubella, ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/immunization-coverage-against-diphtheria-tetanus-and-pertussis-dtp3-vs-gdp-per-capita", "children": [ { "text": "diphtheria, tetanus, pertussis", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/polio-rate-of-cases-vs-vaccination-coverage", "children": [ { "text": "polio", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", rabies, hepatitis B, ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/rotavirus-vaccine", "children": [ { "text": "rotavirus", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/hib-vaccine", "children": [ { "text": "haemophilus influenzae type B", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", and ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds?country=~OWID_WRL", "children": [ { "text": "tuberculosis", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2013 some of which are administered as combined vaccines. We have classified a country as having a mandatory policy if they mandate for at least one vaccine. \u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The differences in vaccination policy across the world are shown in the map. By covering 149 countries we could identify some trends around where and why vaccines are mandatory today.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/mandatory-childhood-vaccination", "type": "chart", "parseErrors": [] }, { "text": [], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Note: this is a live dataset that relies on crowdsourcing to note policy changes. If you are aware of any new policies or policy changes for any country please do get in touch at: [email protected].", "spanType": "span-simple-text" } ], "spanType": "span-italic" } ], "parseErrors": [] }, { "text": [ { "text": "How do mandatory vaccination policies vary by region?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "We found that assessing policies across WHO regions \u2013 European, Americas, Western Pacific, African, and Eastern Mediterranean \u2013 was a useful way to break down our analysis of policies worldwide.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the chart you see a breakdown of the number of countries with a given policy mandate. You can view this by region by using the \"Change region\" toggle on the interactive chart.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Europe has a mixture of mandatory and recommended policies. But most European countries \u00ad\u2013 16 out of 28 \u2013 do not have mandatory vaccination. European countries were among the first to introduce mandatory vaccination for smallpox in the early 19", "spanType": "span-simple-text" }, { "children": [ { "text": "th", "spanType": "span-simple-text" } ], "spanType": "span-superscript" }, { "text": " century, which also led to early push-back. The early introduction and early push-back, along with present-day approaches to foster mutual trust and responsibility between citizens and the health authorities, may be part of the reason why vaccination is often recommended rather than mandated in many European countries.{ref}Stuart Blume (2017) ", "spanType": "span-simple-text" }, { "children": [ { "text": "Immunization: How Vaccines became Controversial - Stuart Blume - Google Books", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". Reaktion Books.{/ref} Countries of the former-USSR (Union of Soviet Socialist Republics) or under the influence of the Eastern Bloc previously had mandatory vaccination, and many kept this policy in the post-USSR era.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Most countries in the Americas \u2013 29 out of 35 \u2013 have mandatory vaccinations. In the USA, vaccination is regulated by individual states though it is mandatory for school entry in all of them. In Canada, only three provinces have legislated mandatory vaccination policies that apply to children enrolling in school.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the Western Pacific region, changes to mandatory policies have gone in both directions. Some countries such as Singapore have moved towards mandatory vaccinations whilst others, such as South Korea transitioned away from mandatory to recommended vaccines in 1999. For other countries, mandatory policies are more ambiguous. In China, there is no evidence of specific legislation mandating vaccines, despite many references to such claims in the literature.{ref}Attwell, K., Drislane, S. and Leask, J. (2019) \u2018Mandatory vaccination and no fault vaccine injury compensation schemes: An identification of country-level policies\u2019, ", "spanType": "span-simple-text" }, { "children": [ { "text": "Vaccine", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". Elsevier Ltd, 37(21), pp. 2843\u20132848. doi: 10.1016/j.vaccine.2019.03.065.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "It was difficult to obtain information about vaccination policies across African countries, suggesting\u00a0the absence of specific policies in the region. However, the policies we did find were for\u00a0mandatory vaccination.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Most countries in the Eastern Mediterranean region have mandatory vaccines. Israel is an exception in only recommending vaccination, based on a vaccination schedule outlined by the National Immunization Technical Advisory\u00a0Group.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are a number of countries in South-East Asia with mandatory vaccination. India is similar to other large countries, with varying policies on mandatory vaccination at the state level. Finally, we note that there are some countries that have mandatory policies at a sub-country level such as in Canadian provinces and Indian and Australian states but we have classified these countries as to the national policy and the policies cover most of the country.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/number-countries-mandatory-vaccination?country=~OWID_WRL", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "What drives the introduction of mandatory vaccinations?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Overall, we found that the occurrence of recent outbreaks is a major factor in the introduction of mandatory vaccination, particularly for high and upper-middle-income countries in Europe. Germany, for example, made measles vaccination mandatory for school and day-care attendance in 2020 following large outbreaks.{ref}Rezza, G. (2019) \u2018Mandatory vaccination for infants and children: the Italian experience\u2019, ", "spanType": "span-simple-text" }, { "children": [ { "text": "Pathogens and Global Health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". Taylor and Francis Ltd., pp. 291\u2013296. doi: 10.1080/20477724.2019.1705021.{/ref} Similarly, Serbia tightened mandatory vaccination laws following a measles outbreak in 2014 to 2015 by introducing harsher penalties.{ref}Pejin LS. Tightening measures for compliance with vaccination in Serbia ESPN Flash Report. European Commission; 2016.{/ref} Trends of reported cases of measles can be explored in detail ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/reported-cases-of-measles?country=~DEU", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Secondly, many low- and lower-middle-income countries have resorted to mandatory vaccination policies because of a lack of other policy options. Nonetheless, many have still missed their target vaccination rates due to problems with vaccine supply, delivery, and access. In Guyana for example, vaccination is mandatory, yet vaccination coverage is hindered by the management of the supply chain in keeping storage temperatures consistent and the distribution of freeze-sensitive vaccines.{ref}UNICEF. Guyana Situation Analysis of Children and Women; 2016. Available at:\u00a0", "spanType": "span-simple-text" }, { "url": "https://www.unicef.org/sitan/", "children": [ { "text": "https://www.unicef.org/sitan/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u00a0[accessed: 10 April 2020].{/ref} In Nigeria, vaccination is mandatory, and several states have enacted legislation criminalising vaccine refusal. Yet as Onyemelukwe (2016) argues, there are structural, logistical, political, systemic, religious and cultural obstacles to the effective distribution and uptake of vaccines, ranging from cold chain issues, to corruption and security issues.{ref}Onyemelukwe, C. (2016) \u2018Can legislation mandating vaccination solve the challenges of routine childhood immunisation in Nigeria?\u2019, ", "spanType": "span-simple-text" }, { "children": [ { "text": "Oxford University Commonwealth Law Journal", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". Taylor and Francis Ltd., 16(1), pp. 100\u2013124. doi: 10.1080/14729342.2016.1244450.{/ref} There is thus often variation between vaccination in policy compared to in practice.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "These findings will be useful to inform policymakers considering the merits of mandatory vaccination:", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "1) In the past, an outbreak of a disease (such as measles) has led to introduction of mandatory vaccines even in countries where previously all vaccinations were recommended;", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "2) Making a vaccine mandatory should not be the only policy tool but needs to be combined with strong access and availability of vaccines;", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "3) It is not just a matter of whether to mandate a vaccine, but how this mandate will be enforced, whether people will comply, and the impact on state-citizen relations. \u00a0 ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In summary, mandatory vaccination must be considered with caution. A country\u2019s past experience with mandates, vaccination services, ability for enforcement, public attitudes, and the current state of disease outbreaks will all play a part in whether mandatory vaccination should be introduced.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Coverage, Impact, and Potential", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Diseases preventable through vaccination", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart shows the number of global deaths caused by some of the most common and serious vaccine-preventable diseases.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "By selecting \u2018change country\u2019 it is possible to see this change for any country in the world and extending the timeline will let you see the change in deaths over time.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are more diseases for which vaccines are available now and even more are under development currently. The WHO publishes list of ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/immunization/diseases/en/", "children": [ { "text": "26 diseases", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " for which vaccines are available \u2013 including Japanese encephalitis, pneumococcal disease, varicella/chicken pox, HPV, Hepatitis A and rotavirus.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/Deaths-caused-by-vaccine-preventable-diseases-over-time", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Diphtheria, Tetanus, and Pertussis vaccine", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Diphtheria, tetanus, and pertussis are all bacterial diseases and a combination vaccine against all three diseases is commonly used. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "list", "items": [ { "type": "text", "value": [ { "text": "Diphtheria primarily infects the throat and upper airways and is fatal in 5 \u2013 10% of cases.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Tetanus is not passed person-to-person but through spores of a bacteria living in soil and animal intestinal tracts. These bacteria enter the body through wounds and release a toxin that affects the nerves, which causes muscle stiffness and spasms.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Pertussis is a highly contagious disease of the respiratory tract, commonly known as whooping cough. Children who contract pertussis tend to have coughing spells that last four to eight weeks, but the highest fatality is in young infants.\u00a0Vaccinating health workers and pregnant women is the most effective strategy for preventing disease in infants too young to be vaccinated. ", "spanType": "span-simple-text" } ], "parseErrors": [] } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart shows the progress over time of DTP3 immunization coverage of children around the world.\u00a0By clicking on any country you can see the change in that country over time.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The WHO ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=OWID_WRL", "children": [ { "text": "reports", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " in 2017 that 85% of infants worldwide (116.5 million infants) received 3 doses of diphtheria-tetanus-pertussis\u00a0vaccine (DTP3). Also in 2016 130 countries had reached at least 90% coverage with the DTP3 vaccine.{ref}See the WHO here: ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/mediacentre/factsheets/fs378/en/", "children": [ { "text": "http://www.who.int/mediacentre/factsheets/fs378/en/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "If we look at ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=East%20Asia%20%26%20Pacific+Europe%20%26%20Central%20Asia+Latin%20America%20%26%20Caribbean+Middle%20East%20%26%20North%20Africa+North%20America+South%20Asia+Sub-Saharan%20Africa", "children": [ { "text": "the change over time by world region", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u00a0it is South Asia in particular that stands out. While 85% of one-year-olds today are immunized, that same figure was as low 6% in 1980.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Within each country there can be substantial differences in vaccination coverage.\u00a0The ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/gho/urban_health/services/dpt3_vaccination/en/", "children": [ { "text": "WHO reports", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " that in all regions children in the richest 20% of urban households are more likely to get immunized than children from the poorest 20% of households.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Some countries lag behind however. Ukraine stands out as having particularly low DTP vaccination rates in 2015 of 23%, falling from 98% in 1999. Ed Holt writing for the Lancet in 2013 attributed the decline to: \"A combination of public mistrust in vaccinations, poor vaccine supply, and corruption in the health system\".{ref}Holt, Ed., Ukraine at risk of polio outbreak, The Lancet , Volume 381 , Issue 9885 , 2244 ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/23819156", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} Therefore Ukraine is suffering from a combination of factors effecting vaccination rates from public attitudes and systemic delivery problems. Furthermore, the unrest since 2014 and Russian military intervention is likely to have worsened matters. Today only Equatorial Guinea reports even lower rates at 16%. As ", "spanType": "span-simple-text" }, { "url": "https://www.hrw.org/world-report/2015/country-chapters/equatorial-guinea", "children": [ { "text": "Human Rights Watch observes", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", very little of the country's wealth is being directed towards the needs of citizens.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The number of under-vaccinated children in Nigeria remains high, with ", "spanType": "span-simple-text" }, { "url": "http://www.gavi.org/library/news/statements/2017/vaccine-progress-in-developing-countries-in-danger-of-stalling/", "children": [ { "text": "3.4 million children going without the DTP3 vaccine (compared with 2.9 million in India", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ").", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-of-children-immunized-dtp3", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Measles vaccine", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Measles is a\u00a0highly contagious virus-caused disease that, despite a safe and effective vaccine being available, infects thousands of people globally. Around 90,000 people die because of measles every year, the huge majority of whom (87%) are children younger than 5. Measles vaccination has resulted in an 84% drop in measles deaths between 2000-2016.{ref}Figures are updated by the WHO here: http://www.who.int/news-room/fact-sheets/detail/measles{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The world map shows the share of children vaccinated with the first dose of measles vaccine.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "You can switch to the 'chart' view to see the global coverage against vaccines. The measles vaccine was developed in 1963. In 1983 \u2013 the first year for which global data is available \u2013 only every second child was vaccinated against measles. In the latest data this share has increased to 85% globally up from 72% in 2000.{ref}See the WHO here: ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/mediacentre/factsheets/fs286/en/", "children": [ { "text": "http://www.who.int/mediacentre/factsheets/fs286/en/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The sub-Saharan African region achieves the lowest measles vaccination rates, along with conflict-ridden and unstable countries (e.g. Syria, Afghanistan, and Iraq). But also some of the Pacific Islands \u2013 such as Papua New Guinea and Vanuatu \u2013 are performing poorly.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Today (data from 2014) 114.3 million children are vaccinated against measles every year, which is on average 313,071 children every single day.{ref}In 2014 there were ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/number-of-one-year-olds", "children": [ { "text": "135.2 million one-year olds", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". Of these ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles?tab=chart", "children": [ { "text": "84.52% received the vaccine against measles", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": " This means that 135.2 *0.8452 =\u00a0114.27 million children were vaccinated.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Second dose of measles vaccine provides greater protection", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "As of 2018, the WHO estimate that 171 countries had included a second dose as part of routine immunization. Two doses are needed for a higher level of protection.{ref}Gaston De Serres, Jill Sciberras, Monika Naus, Nicole Boulianne, Bernard Duval, and Louis Rochette (1999) \u2013\u00a0Protection after Two Doses of Measles Vaccine Is Independent of Interval between Doses. In The Journal of Infectious Diseases, Volume 180, Issue 1, 1 July 1999, Pages 187\u2013190, ", "spanType": "span-simple-text" }, { "url": "https://doi.org/10.1086/314847", "children": [ { "text": "https://doi.org/10.1086/314847", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " Online here: ", "spanType": "span-simple-text" }, { "url": "https://academic.oup.com/jid/article/180/1/187/990623", "children": [ { "text": "https://academic.oup.com/jid/article/180/1/187/990623", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The map here shows the coverage of the second dose (MCV2) of the measles vaccine. The current global average is 67%. The coverage is lowest in South Africa and many countries in Sub-Saharan Africa still have not introduced the vaccine into their immunization coverage.{ref}For guidelines on recommendations for the second dose of measles vaccine see here ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf", "children": [ { "text": "https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "url": "https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles-vs-share-vaccinated-against-dpt3", "children": [ { "text": "This scatterplot", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " compares the vaccination coverage against measles with the coverage against DTP3.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-of-children-vaccinated-with-mcv2", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Global decline of measles", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The second visualization shows the discussed increase of the global vaccination coverage of one-year-olds and the simultaneous decline of reported cases of the disease; from close to 1,000 cases per million people globally to 28 cases per million. This represents a 33-fold reduction.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "For country by country change over time see ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/reported-cases-of-measles", "children": [ { "text": "this visualization", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Rotavirus vaccines", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The first widely-used rotavirus vaccine was approved in the United States in 2006. Today, there are four oral rotavirus vaccines recommended for use by the World Health Organisation (WHO): Rotarix, RotaTeq, RotaSiil, and Rotavac.{ref}World Health Organization. (2019). ", "spanType": "span-simple-text" }, { "children": [ { "text": "Rotavirus", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". [online] Available at: ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/immunization/diseases/rotavirus/en/", "children": [ { "text": "https://www.who.int/immunization/diseases/rotavirus/en/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " [Accessed 14 Aug. 2019].{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": " Rotarix and RotaTeq are the most widely used and both have shown good efficacy against rotavirus infections in clinical trials.{ref}Ruiz-Palacios, G. M., P\u00e9rez-Schael, I., Vel\u00e1zquez, F. R., Abate, H., Breuer, T., Clemens, S. C., \u2026 & Cervantes, Y. (2006). ", "spanType": "span-simple-text" }, { "url": "https://www.nejm.org/doi/full/10.1056/nejmoa052434", "children": [ { "text": "Safety and efficacy of an attenuated vaccine against severe rotavirus gastroenteritis", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "New England Journal of Medicine", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "354", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(1), 11-22.{/ref}{ref}Vesikari, T., Matson, D. O., Dennehy, P., Van Damme, P., Santosham, M., Rodriguez, Z., \u2026 & Shinefield, H. R. (2006). ", "spanType": "span-simple-text" }, { "url": "https://www.nejm.org/doi/full/10.1056/nejmoa052664", "children": [ { "text": "Safety and efficacy of a pentavalent human\u2013bovine (WC3) reassortant rotavirus vaccine", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "New England Journal of Medicine", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "354", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(1), 23-33.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Since the use of rotavirus vaccines have been approved, they have had a notable impact on the reduction of rotavirus-related deaths. According to a study published in 2018, the use of rotavirus vaccines prevented approximately 28,900 child deaths globally in 2016. However, as the chart shows, full vaccine use \u2013 that is a 100% coverage globally \u2013 could have prevented an additional 83,200 deaths.{ref}Troeger, C., Khalil, I. A., Rao, P. C., Cao, S., Blacker, B. F., Ahmed, T., \u2026 & Kang, G. (2018). ", "spanType": "span-simple-text" }, { "url": "https://jamanetwork.com/journals/jamapediatrics/fullarticle/2696431", "children": [ { "text": "Rotavirus vaccination and the global burden of rotavirus diarrhea among children younger than 5 years", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "JAMA Pediatrics", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "172", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(10), 958-965.{/ref} This means that, even at the current rates of efficacy, 53% of all deaths in children under-5 from rotavirus in 2016 could have been avoided by full vaccine coverage. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In addition to saving lives, the rotavirus vaccine also reduces the burden on healthcare systems. Between 2008 and 2016 the introduction of the rotavirus vaccine has reduced the number of diarrhea-related hospital admissions on average by 40%.{ref}Aliabadi, Negar, et al. ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(19)30207-4/fulltext", "children": [ { "text": "\"Global impact of rotavirus vaccine introduction on rotavirus hospitalisations among children under 5 years of age, 2008\u201316: findings from the Global Rotavirus Surveillance Network.\"", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "The Lancet Global Health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "7.7 (2019): e893-e903.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/avertable-deaths-from-rotavirus-with-full-vaccine-coverage", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Rotavirus vaccine could save the lives of even more children", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "If there is so much scope for saving more children\u2019s lives, what is the reason that these children are still dying?", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are two key barriers to achieving the full potential of the rotavirus vaccine: immunization rates, and the efficacy of the vaccine in specific regions.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Immunisation rates are still too low", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "According to the WHO, by the end of 2018, 101 countries were using the rotavirus vaccine. The major drivers for the introduction of the vaccine are the burden of diarrheal diseases, the availability of funding, and a favourable political climate for vaccines.{ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The cost of rotavirus vaccines varies by country. For example, countries with a gross national income per capita of less than US$1,000 receive subsidies from the Global Alliance for Vaccines and Immunisation, and there the cost per dose is ", "spanType": "span-simple-text" }, { "url": "https://www.unicef.org/supply/files/Rotavaccine.pdf", "children": [ { "text": "set between US$2.10 - 3.20", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". With additional co-financing options can reduce the costs ", "spanType": "span-simple-text" }, { "url": "https://www.sabin.org/sites/sabin.org/files/frederic_debellut.pdf", "children": [ { "text": "down to US$0.13", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". In high-income countries, such as the US, the cost per dose is between ", "spanType": "span-simple-text" }, { "url": "https://www.cdc.gov/vaccines/programs/vfc/awardees/vaccine-management/price-list/index.html", "children": [ { "text": "US$70 and 95", "spanType": "span-simple-text" } ], "spanType": "span-link" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Countries are more likely to introduce the vaccine if the political environment is favourably disposed towards them. For example, if a country has set a high priority on achieving the Millennium Development Goal targets or the introduction of vaccines is seen as a positive news story, especially during election years.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Burchett, H. E. D., Mounier-Jack, S., Griffiths, U. K., Biellik, R., Ongolo-Zogo, P., Chavez, E., \u2026 & Molla, M. (2012). ", "spanType": "span-simple-text" }, { "url": "https://academic.oup.com/heapol/article/27/suppl_2/ii5/594662", "children": [ { "text": "New vaccine adoption: qualitative study of national decision-making processes in seven low-and middle-income countries", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Health policy and planning", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "27", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(suppl_2), ii5-ii16.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": " The vaccine is only given to children \u2013 it\u2019s recommended that the vaccination should be initiated 15 weeks after birth and finished by the 32nd week. However, the global coverage is still very low: it is estimated that just 35% of under one-year-olds were vaccinated in 2018.{ref}World Health Organization (2019). ", "spanType": "span-simple-text" }, { "children": [ { "text": "Immunization coverage", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". [online] Available at: ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/news-room/fact-sheets/detail/immunization-coverage", "children": [ { "text": "https://www.who.int/news-room/fact-sheets/detail/immunization-coverage", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " [Accessed 14 Aug. 2019].{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The map shows the WHO estimates on the share of one-year olds who received the full recommended dosage of the vaccine (two immunizations for Rotarix vaccine or three immunizations for RotaTeq vaccine). For many countries where data coverage is low, it\u2019s expected that the share of infants receiving the vaccine is very low. Some countries however did see rapid increases in rates of immunization. In a period of only a few years countries including ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine?tab=chart&time=2011..2018&country=SDN+GMB+MWI", "children": [ { "text": "Sudan, Malawi and Gambia", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " have increased immunisation rates from below 10% to 80-95% \u2013 click on the country to see the change over time.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Vaccine efficacy differs by region", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Since most ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/child-deaths-from-rotavirus", "children": [ { "text": "rotavirus cases", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " occur in Sub-Saharan Africa where ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/child-mortality-rate-from-rotavirus?tab=chart", "children": [ { "text": "mortality from rotavirus infection is also the highest", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", it is essential to increase and maintain high immunisation coverage in this region. However, in addition to delivering the vaccine for those who need it, we also need to work on improving its efficacy.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Vaccine efficacy for the rotavirus vaccine is defined as the percentage reduction of the rate of diarrhea incidences in vaccinated versus unvaccinated groups of children. It is well established that the efficacy of the rotavirus vaccine is not the same across all countries \u2014 in countries with high child mortality rates the vaccine shows much lower efficacy.{ref}Clark, Andrew, et al. ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext", "children": [ { "text": "\"Efficacy of live oral rotavirus vaccines by duration of follow-up: a meta-regression of randomised controlled trials.\"", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "The Lancet Infectious Diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (2019).{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart is from a recent study by Clark et ", "spanType": "span-simple-text" }, { "children": [ { "text": "al.", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", which looked at how the efficacy of live oral rotavirus vaccines changes in different countries following vaccination. The chart shows that in countries with high child mortality rates, not only is the immediate vaccine efficacy lower \u2013 98% in low child mortality countries versus 66% in high child mortality countries \u2013 but also the vaccine efficacy decreases faster in high child mortality countries over time.{ref}The ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext", "children": [ { "text": "Clark et al.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " (2019) study defined low child mortality rate as less than 1.3% of newborns; medium mortality rate as between 1.35% and 2.81%; and high mortality rate as more than 2.81%{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": " Five years after vaccination, the rotavirus vaccine reduces the chances of getting diarrhea by 90% in low child mortality countries and only by 30% in high mortality countries.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "alt": "", "size": "wide", "type": "image", "filename": "Rotavirus-vaccine-efficacy-by-child-mortality-group-1.png", "parseErrors": [] }, { "type": "text", "value": [ { "text": "The table shows how good the rotavirus vaccine is at preventing severe diarrhea and reducing hospitalization due to diarrhea in children under-5 in different regions.{ref}Lamberti, L. M., Ashraf, S., Walker, C. L. F., & Black, R. E. (2016). ", "spanType": "span-simple-text" }, { "url": "https://www.ingentaconnect.com/content/wk/inf/2016/00000035/00000009/art00016", "children": [ { "text": "A systematic review of the effect of rotavirus vaccination on diarrhea outcomes among children younger than 5 years", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "The Pediatric Infectious Disease Journal", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "35", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(9), 992-998.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": " In high-income countries, rotavirus vaccination has been shown to reduce the cases of severe rotavirus diarrhea by 91% and hospitalization by 94%. In Eastern Asia and Latin America, the effectiveness rates are lower but still high \u2013 preventing 88% and 80% of severe diarrhea cases, respectively. However, effectiveness in South Asia and Sub-Saharan Africa is significantly lower, only reducing severe diarrhea in around half of the cases.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "html", "value": "<div class=\"raw-html-table__container\"><table><thead><tr><th scope=\"col\" colspan=\"1\">Outcome </th><th scope=\"col\" colspan=\"1\">Region</th><th scope=\"col\" colspan=\"1\">Vaccine effectivness</th></tr></thead><tbody><tr><td colspan=\"1\" rowspan=\"5\">Severe rotavirus diarrhea</td><td colspan=\"1\" rowspan=\"1\">Developed</td><td colspan=\"1\" rowspan=\"1\">91%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Eastern Asia and Southeast Asia</td><td colspan=\"1\" rowspan=\"1\">88%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Latin America and Caribbean</td><td colspan=\"1\" rowspan=\"1\">80%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Southern Asia</td><td colspan=\"1\" rowspan=\"1\">50%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Sub-Saharan Africa</td><td colspan=\"1\" rowspan=\"1\">46%</td></tr><tr><td colspan=\"1\" rowspan=\"4\">Hospitalization due to rotavirus infection</td><td colspan=\"1\" rowspan=\"1\">Developed</td><td colspan=\"1\" rowspan=\"1\">94%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Eastern Asia and Southeast Asia</td><td colspan=\"1\" rowspan=\"1\">94%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Latin America and Caribbean</td><td colspan=\"1\" rowspan=\"1\">84%</td></tr><tr><td colspan=\"1\" rowspan=\"1\">Sub-Saharan Africa</td><td colspan=\"1\" rowspan=\"1\">58%</td></tr></tbody></table></div>", "parseErrors": [] }, { "type": "text", "value": [ { "text": "The reasons for different responses to the vaccine are not entirely clear.{ref}Patel, M., Shane, A. L., Parashar, U. D., Jiang, B., Gentsch, J. R., & Glass, R. I. (2009). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3673012/#R3", "children": [ { "text": "Oral rotavirus vaccines: how well will they work where they are needed most?", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "The Journal of Infectious Diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "200", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", S39-S48.{/ref} {ref}Parker, E. P., Ramani, S., Lopman, B. A., Church, J. A., Iturriza-Gomara, M., Prendergast, A. J., & Grassly, N. C. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.futuremedicine.com/doi/10.2217/fmb-2017-0128?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dwww.ncbi.nlm.nih.gov&", "children": [ { "text": "Causes of impaired oral vaccine efficacy in developing countries", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Future microbiology", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "13", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(1), 97-118.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": " It is likely that the gut responses to the oral rotavirus vaccines in children in lower-income countries are different. This may be due to a variety of causes, including ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/micronutrient-deficiency", "children": [ { "text": "micronutrient deficiencies", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", pre-vaccination exposure to certain pathogens, and the presence of chronic conditions such as ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/malaria", "children": [ { "text": "malaria", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " or ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/hiv-aids", "children": [ { "text": "HIV", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". Overall, the poor gut response to the live vaccine means the efficacy of the vaccine is reduced. Taking all of the above mentioned points into account, there are several interventions that could increase the benefits of the rotavirus vaccine even further. In addition to increasing the vaccine coverage, improving nutritional health (of both infants and mothers) and improving hygiene and sanitation conditions (to lower the prevalence of damaging pathogens) could have positive effects on the vaccine\u2019s efficacy.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "We are still at quite an early stage of the rotavirus vaccine use. Although the vaccine has brought huge benefits already, it could go even further. Improving vaccination coverage, particularly across Sub-Saharan Africa and South Asia is key to continued reduction of childhood deaths from diarrhea. Even at moderate levels of vaccine efficacy, a significant number of additional additional child deaths could be prevented every year. The bar chart above that shows the number of preventable deaths illustrates the potential for extended vaccine coverage to save many more lives. And this is already taking into account the regional differences in the vaccine\u2019s effectiveness.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In addition to increased coverage, improving the effectiveness of the vaccine would go even further in tackling one of the leading causes of death.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Pneumococcal vaccines", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are a number of ways we could reduce the number of children dying from pneumonia, including eliminating the major risk factors such as ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/hunger-and-undernourishment", "children": [ { "text": "undernutrition", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " and ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/indoor-air-pollution", "children": [ { "text": "air pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", and providing better ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/pneumonia-careseeking", "children": [ { "text": "access to treatment", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But we have another highly effective intervention: a ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/vaccination", "children": [ { "text": "vaccine", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " against the major pathogen responsible for pneumonia in children. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Streptococcus pneumoniae ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "is the leading cause of pneumonia in children under 5 \u2014 it was responsible for 52% of all fatal pneumonia cases in children in 2016.{ref}Troeger, C., Blacker, B., Khalil, I. A., Rao, P. C., Cao, J., Zimsen, S. R., ... & Adetifa, I. M. O. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(18)30310-4/fulltext", "children": [ { "text": "Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory infections in 195 countries, 1990\u20132016: a systematic analysis for the Global Burden of Disease Study 2016.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " The Lancet Infectious Diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "18", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(11), 1191-1210.{/ref} Pneumococcal vaccines are vaccines that target ", "spanType": "span-simple-text" }, { "children": [ { "text": "S. pneumoniae", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " bacteria. Here we look at their effectiveness and how we can maximise the number of children they save.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "The coverage of pneumococcal vaccines is still low", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Since the World Health Organisation (WHO) started recommending including pneumococcal vaccines in national immunisation programmes for children in 2007, there has been a progressive increase in the number of countries using the vaccine. You can see the uptake in the vaccine across the world using the \u2018play\u2019 button on the map below. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But the coverage of pneumococcal vaccines is still low in many countries. In India and Nigeria \u2013 the two countries with the ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5", "children": [ { "text": "greatest number", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " of childhood deaths from pneumonia in 2019 \u2013 only 44% and 58% of one-year-olds are vaccinated, respectively.\u00a0 ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In 2018, less than half (47%) of one-year-olds in the world received the full course of pneumococcal vaccination. This means that 55 million children who could be protected by the vaccine are still not vaccinated against it\u00a0\u2014 an appallingly high number for a vaccine that not only protects from pneumonia, the leading cause of childhood death, but also a range of other diseases (as discussed below).{ref}Who.int. (2019) \u2013 ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/news-room/fact-sheets/detail/immunization-coverage", "children": [ { "children": [ { "text": "Immunization coverage", "spanType": "span-simple-text" } ], "spanType": "span-italic" } ], "spanType": "span-link" }, { "text": ". [online] [Accessed 10 Sep. 2019]. ", "spanType": "span-simple-text" }, { "url": "http://view-hub.org/viz/", "children": [ { "text": "http://view-hub.org/viz/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " (Go to PCV \u2014>\u00a0 PCV - Vaccine Access \u2014> Children without Access){/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "How do pneumococcal vaccines work?", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Streptococcus pneumonia", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", often simply referred to as pneumococcus, is a bacterium that is often found in the upper respiratory tract of healthy people. Generally, the bacterium is harmless or causes milder illnesses such as bronchitis, sinusitis, and ear infections. Pneumococcal vaccines are effective against these milder illnesses as well, but importantly also protects from what is called pneumococcal invasive disease (PID). PID occurs when the pneumococcus moves from colonizing the upper respiratory tract to colonizing sites that are normally sterile, such as blood, cerebrospinal fluid or pleural cavity (fluid-filled space surrounding the lungs).{ref}Hanada, S., Pirzadeh, M., Carver, K. Y., & Deng, J. C. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6250824/", "children": [ { "text": "Respiratory Viral Infection-Induced Microbiome Alterations and Secondary Bacterial Pneumonia.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "Frontiers in immunology", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "9", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", 2640.{/ref} Bacterial invasion leads to life-threatening diseases such as sepsis, meningitis and severe pneumonia.\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/child-deaths-from-streptococcus-by-disease", "type": "chart", "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are two types of pneumococcal vaccines available: conjugated polysaccharide pneumococcal vaccine (PCV) and non-conjugated polysaccharide pneumococcal vaccine (PPSV). Both vaccines are designed to elicit immune responses against multiple serotypes of pneumococcus, which are defined by the different immune responses to the sugars found on the bacterial surface.{ref}Song, J. Y., Nahm, M. H., & Moseley, M. A. (2013). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3546102/", "children": [ { "text": "Clinical implications of pneumococcal serotypes: invasive disease potential, clinical presentations, and antibiotic resistance", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Journal of Korean medical science", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "28", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(1), 4-15.{/ref} To be broadly effective, the vaccines need to protect against a certain number of these pneumococcal serotypes, but it is not necessary to include all possible serotypes because only a limited subset is responsible for 70%-80% of invasive pneumococcal disease.{ref}The number of serotypes included in the vaccine is generally indicated in its name, e.g. PCV13 is pneumococcal conjugate vaccine effective against 13 bacterial serotypes. Vaccines including progressively more serotypes have been introduced over the years, PCV7 was introduced in 2000 and today the most commonly used PCV13 was introduced in 2010.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Hausdorff, W. P., Feikin, D. R., & Klugman, K. P. (2005). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/15680778/", "children": [ { "text": "Epidemiological differences among pneumococcal serotypes.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "The Lancet infectious diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "5", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(2), 83-93.{/ref} However, as we\u2019ll discuss later, this variety of different pneumococcal serotypes is important to keep in mind because as vaccine coverage increases we may see a replacement of the vaccine-included serotypes with the less dominant ones, which will mean new vaccine versions will be required.\u00a0\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "While there are two types of pneumococcal vaccines available, for children under two years old only the conjugated (i.e. PCV) vaccines are recommended because the non-conjugated versions (i.e. PPSV) are not effective at such a young age.{ref}The current non-conjugate vaccine, PPSV23, is generally only given to adults or as a single dose following two immunisations with PCV13 in children older than 2.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Golos, M., Eliakim\u2010Raz, N., Stern, A., Leibovici, L., & Paul, M. (2016). ", "spanType": "span-simple-text" }, { "url": "https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD012306/full", "children": [ { "text": "Conjugated pneumococcal vaccine versus polysaccharide pneumococcal vaccine for prevention of pneumonia and invasive pneumococcal disease in immunocompetent and immunocompromised adults and children.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "Cochrane Database of Systematic Reviews", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", (8).{/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "How effective are pneumococcal vaccines?", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "In clinical trials PCV has shown 80% efficacy in reducing invasive pneumococcal disease caused by the bacterial serotypes included in the vaccine formulation. Vaccinated children are 27% less likely to be diagnosed with pneumonia and 11% less likely to die from it.{ref}The 27% refers to X-ray-defined cases of pneumonia. For clinically defined pneumonia, a less accurate diagnosis than X-ray-defined cases, the number is 6%. Both of these indicators refer to cases of pneumonia caused by any pathogen not only pneumococcus.\u00a0\u00a0Lucero, M. G., Dulalia, V. E., Nillos, L. T., Williams, G., Parre\u00f1o, R. A. N., Nohynek, H., ... & Makela, H. (2009). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6464899/", "children": [ { "text": "Pneumococcal conjugate vaccines for preventing vaccine\u2010type invasive pneumococcal disease and X\u2010ray defined pneumonia in children less than two years of age", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Cochrane Database of Systematic Reviews", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", (4).{/ref} ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Several studies have attempted to estimate how many lives PCV vaccination has saved and could possibly save. One ", "spanType": "span-simple-text" }, { "children": [ { "text": "Lancet ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "study concluded that between 2000 and 2015, in 120 countries the number of childhood deaths caused by pneumococcus fell from 600,000 to 294,000 \u2014 a decline of 54%. Most of this decline was attributed to the PCV vaccines: over this period, it\u2019s estimated these vaccines saved the lives of 250,000 children. The majority of these deaths would have been caused by pneumonia, but the vaccine also prevented deaths from pneumococcal meningitis and other diseases.{ref}Wahl, B., O'Brien, K. L., Greenbaum, A., Majumder, A., Liu, L., Chu, Y., ... & Rudan, I. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30247-X/fulltext", "children": [ { "text": "Burden of Streptococcus pneumoniae and Haemophilus influenzae type b disease in children in the era of conjugate vaccines: global, regional, and national estimates for 2000\u201315.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " The Lancet Global Health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "6", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(7), e744-e757.{/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "How many child deaths could be averted by pneumococcal vaccines?", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart shows how estimates of the potential impact of the pneumococcal vaccine.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "It is based on a recent study published in ", "spanType": "span-simple-text" }, { "children": [ { "text": "The Lancet Global Health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " journal, which calculated that if the PCV vaccine coverage would reach at least the levels of the ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-children-immunized-dtp3", "children": [ { "text": "vaccination against diphtheria, tetanus and pertussis", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " (DTP3), the lives of 399,000 children under 5 could be saved.{ref}Chen, C., Liceras, F. C., Flasche, S., Sidharta, S., Yoong, J., Sundaram, N., & Jit, M. (2019). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30422-4/fulltext", "children": [ { "text": "Effect and cost-effectiveness of pneumococcal conjugate vaccination: a global modelling analysis.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " The Lancet Global Health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "7", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(1), e58-e67.{/ref} Additionally the researchers estimate that 54.6 million pneumonia episodes annually could be averted.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "These number estimate the impact of the PCV vaccination relative to a world without that vaccine \u2013 since the vaccine is already used it means that some of these lives are already being saved by the PVC vaccination. However, in many countries ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/diphtheria-tetanus-pertussis-vaccine-vs-pneumococcal-vaccine-coverage", "children": [ { "text": "PCV vaccination rates still fall far below the DTP3 rates", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", making clear that we still haven\u2019t used the pneumococcal vaccine to its full potential.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/pneumococcal-vaccination-averted-deaths", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "What can we do to improve the coverage and effectiveness of\u00a0 pneumococcal vaccines?", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "A continued increase in immunization coverage and the introduction of PCV vaccines into countries which don\u2019t yet use them is important if we want to make use of the full potential of pneumococcal vaccines.\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "PCV vaccines are amongst the most expensive vaccines in national immunisation programmes. The price ranges from $3.05 per dose in GAVI{ref}\u00a0GAVI (Global Alliance for Vaccines and Immunisation) is a non-profit organisation that provides access to vaccination programs for low-income countries by providing financial support and individual expertise.{/ref} supported low-income countries to $169 in high-income countries such as the United States.{ref}O'Brien, K. L. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc", "children": [ { "text": "When less is more: how many doses of PCV are enough?.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " The Lancet Infectious Diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "18", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(2), 127-128.{/ref} For low-middle-income countries who are transitioning from GAVI support the increasing future costs of vaccination place a considerable strain on national healthcare budgets.{ref}For example Kenya has recently entered a transition phase during which it will pay a larger and larger portion of the PCV vaccine cost. By 2027 Kenya will have to pay the full $9 price for a three-dose course child vaccination. The 2016 ", "spanType": "span-simple-text" }, { "url": "https://databank.worldbank.org/Kenya-healthcare-per-capita-/id/58f0a890", "children": [ { "text": "per capita healthcare expenditure in Kenya", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " was around $66 (5% of the GDP), clearly $9 per child is not a trivial cost.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Simonsen, L., van Wijhe, M., & Taylor, R. (2019). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext", "children": [ { "text": "Are expensive vaccines the best investment in low-income and middle-income countries?", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "The Lancet Global Health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "7", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(5), e548-e549.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Ojal, J., Griffiths, U., Hammitt, L. L., Adetifa, I., Akech, D., Tabu, C., ... & Flasche, S. (2019). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext", "children": [ { "text": "Sustaining pneumococcal vaccination after transitioning from Gavi support: a modelling and cost-effectiveness study in Kenya.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " The Lancet Global Health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "7", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(5), e644-e654.{/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "But given the high burden of pneumococcal diseases, even at high prices, PCV vaccines are considered to be cost-effective, with an estimated return of investment in low- and middle-income countries of around 3.{ref}The return of investment was estimated for a projected coverage for individual countries for the decade between 2011 and 2020. It means that the economic benefits (as measured by the costs of vaccination program subtracted from the reduced costs of treatment and productivity loss) of using the vaccine are 3 times higher than no vaccine use.\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "To reduce costs, some countries may also consider switching to a two rather than three dose immunization schedule, but more research on the effectiveness of this schedule in different countries is needed. See O'Brien et al. (2018) reference.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Nakamura, M. M., Tasslimi, A., Lieu, T. A., Levine, O., Knoll, M. D., Russell, L. B., & Sinha, A. (2011). ", "spanType": "span-simple-text" }, { "url": "https://academic.oup.com/inthealth/article-lookup/doi/10.1016/j.inhe.2011.08.004", "children": [ { "text": "Cost effectiveness of child pneumococcal conjugate vaccination in middle-income countries.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "International health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "3", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(4), 270-281.", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Ozawa, S., Clark, S., Portnoy, A., Grewal, S., Brenzel, L., & Walker, D. G. (2016). ", "spanType": "span-simple-text" }, { "url": "https://www.healthaffairs.org/doi/full/10.1377/hlthaff.2015.1086?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed", "children": [ { "text": "Return on investment from childhood immunization in low-and middle-income countries, 2011\u201320.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "Health Affairs", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "35", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(2), 199-207.", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Center, I. V. A. (2017). ", "spanType": "span-simple-text" }, { "url": "https://www.jhsph.edu/ivac/wp-content/uploads/2018/05/PCVEvidenceBase-Jan2017.pdf", "children": [ { "text": "The evidence base for pneumococcal conjugate vaccines (PCVs): data for decision-making around PCV use in childhood.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "Baltimore (MD): Johns Hopkins University", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Goldblatt, D., Southern, J., Andrews, N. J., Burbidge, P., Partington, J., Roalfe, L., ... & Snape, M. D. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30654-0/fulltext", "children": [ { "text": "Pneumococcal conjugate vaccine 13 delivered as one primary and one booster dose (1+ 1) compared with two primary doses and a booster (2+ 1) in UK infants: a multicentre, parallel group randomised controlled trial.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "The Lancet Infectious Diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "18", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(2), 171-179.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "O'Brien, K. L. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc", "children": [ { "text": "When less is more: how many doses of PCV are enough?.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "children": [ { "text": "The Lancet Infectious Diseases", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "18", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(2), 127-128.{/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "PCV vaccines include a limited subset of possible pneumococcal serotypes. The distribution of pneumococcal serotypes is known to vary between countries and PCV vaccines include the ones that are most common globally. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Which non-vaccine serotypes are most common in a particular country, may affect the potential for a particular vaccine\u2019s impact. However, not all countries collect data on serotype distribution, and an assessment of the potential impact is therefore compromised.{ref}Adegbola, R. A., DeAntonio, R., Hill, P. C., Roca, A., Usuf, E., Hoet, B., & Greenwood, B. M. (2014). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/25084351", "children": [ { "text": "Carriage of Streptococcus pneumoniae and other respiratory bacterial pathogens in low and lower-middle income countries: a systematic review and meta-analysis", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "PloS one", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "9", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(8), e103293.{/ref} {ref}Megiddo, I., Klein, E., & Laxminarayan, R. (2018). ", "spanType": "span-simple-text" }, { "url": "https://gh.bmj.com/content/3/3/e000636", "children": [ { "text": "Potential impact of introducing the pneumococcal conjugate vaccine into national immunisation programmes: an economic-epidemiological analysis using data from India.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " BMJ global health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "3", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(3), e000636.{/ref} {ref}Johnson, H. L., Deloria-Knoll, M., Levine, O. S., Stoszek, S. K., Hance, L. F., Reithinger, R., ... & O'Brien, K. L. (2010). ", "spanType": "span-simple-text" }, { "url": "https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1000348", "children": [ { "text": "Systematic evaluation of serotypes causing invasive pneumococcal disease among children under five: the pneumococcal global serotype project.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "PLoS medicine", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "7", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(10), e1000348.{/ref} Notably, since the PCV vaccine was introduced, there has been a rise in pneumococcal invasive disease incidences caused by the less common serotypes. This suggests that, by reducing the prevalence of vaccine-included serotypes, the vaccine unintentionally provides space for non-vaccine serotypes, against which it works less well.{ref}World Health Organization. (2010). ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/wer/2010/wer8543.pdf?ua=1", "children": [ { "text": "Changing epidemiology of pneumococcal serotypes after introduction of conjugate vaccine: July 2010 report.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " Weekly Epidemiological Record [Relev\u00e9 \u00e9pid\u00e9miologique hebdomadaire", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "], ", "spanType": "span-simple-text" }, { "children": [ { "text": "85", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(43), 434-436.{/ref} This means that the vaccine's effectiveness may decrease over time, if the serotype formulation of PCV is not continually reevaluated. In the future, new versions of pneumococcal vaccines may be needed that work better independently of the bacterial serotype. Such vaccines are already in development.{ref}Pichichero, M. E. (2017). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277969/", "children": [ { "text": "Pneumococcal whole-cell and protein-based vaccines: changing the paradigm", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Expert review of vaccines", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "16", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(12), 1181-1190.{/ref} {ref}Ginsburg, A. S., Nahm, M. H., Khambaty, F. M., & Alderson, M. R. (2012). Issues and challenges in the development of pneumococcal protein vaccines. Expert review of vaccines, 11(3), 279-285{/ref} ", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "text": [ { "text": "Hepatitis B vaccine", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart here shows the coverage for Hepatitis B vaccination.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Hepatitis B (HepB)\u00a0is a highly contagious viral infection that attacks the liver and is transmitted through contact with the blood or other body fluids of an infected person. As the chart shows, it is estimated that about 100,000 people die each year\u00a0of chronic liver disease due to hepatitis B. The WHO recommends that all infants should receive their first dose of vaccine as soon as possible after birth, preferably within 24 hours.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/immunization-hepb3-of-one-year-old-children", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Haemophilus influenzae type b vaccine", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Haemophilus influenzae type b (Hib)\u00a0is a bacterial infection that causes meningitis and pneumonia transmitted through the respiratory tract from infected to susceptible individuals. The chart here shows the coverage for Hib vaccination.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/hib-vaccine", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Polio vaccine", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart here shows the coverage of the polio vaccine.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Poliomyelitis (OPV, IPV)\u00a0is a highly infectious viral disease. Once the poliovirus invades the nervous system it can cause irreversible paralysis in a matter of hours. No cure exists for polio, only treatment to alleviate symptoms. As we detail in our\u00a0", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/polio", "children": [ { "text": "entry on polio", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " the world is on its way to eradicate the disease thanks to the vaccine against the virus: While in the 1980s there were 350,000 paralytic cases of polio every year, the world saw only 42 cases in 2016. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/polio-vaccine-coverage-of-one-year-olds", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Tuberculosis vaccine (BCG)", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart here shows the coverage of the BCG vaccine, which protects against tuberculosis.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Developed more than a century ago, bacille Calmette\u2013Gu\u00e9rin vaccine (BCG) is currently the only vaccine available against tuberculosis (TB).\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Close to 4 billion people have been vaccinated with BCG - this makes it the most widely used vaccine in the world.{ref}Kendig, E. L., Wilmott, R. W., & Chernick, V. (2012). ", "spanType": "span-simple-text" }, { "url": "https://www.sciencedirect.com/science/article/pii/B9780323448871000298", "children": [ { "children": [ { "text": "Kendig and Chernick's disorders of the respiratory tract in children", "spanType": "span-simple-text" } ], "spanType": "span-italic" } ], "spanType": "span-link" }, { "text": ". 9th ed. Elsevier Health Sciences.{/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "BCG vaccine is based on a reduced-virulence strain of ", "spanType": "span-simple-text" }, { "children": [ { "text": "Mycobacterium bovis", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", a bacterium that is closely related to ", "spanType": "span-simple-text" }, { "children": [ { "text": "Mycobacterium tuberculosis", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " - the pathogen that causes TB. BCG vaccine was already used in the 1920s in Belgium and France in small trials and after the Second World War its use was expanded to vaccinate children across Europe. In 1950s the WHO started recommending the use of BCG globally.\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "BCG is effective at protecting children and adolescents from severe forms of TB and meningitis.{ref}\u00a0Rodrigues, L. C., Mangtani, P., & Abubakar, I. (2011).", "spanType": "span-simple-text" }, { "url": "https://www.bmj.com/content/343/bmj.d5974.full", "children": [ { "text": " How does the level of BCG vaccine protection against tuberculosis fall over time?", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Bmj", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "343", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", d5974.{/ref} {ref}Rodrigues, L. C., Diwan, V. K., & Wheeler, J. G. (1993). ", "spanType": "span-simple-text" }, { "url": "https://academic.oup.com/ije/article-abstract/22/6/1154/650235", "children": [ { "text": "Protective effect of BCG against tuberculous meningitis and miliary tuberculosis: a meta-analysis.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "International journal of epidemiology", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "22", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(6), 1154-1158.{/ref} However, studies have shown that the length of protection provided by the vaccine varies greatly depending on the populations studied: from 15 years in the UK to 50\u201360 years in Alaska.{ref}Sterne, J. A. C., Rodrigues, L. C., & Guedes, I. N. (1998).", "spanType": "span-simple-text" }, { "url": "https://www.ingentaconnect.com/content/iuatld/ijtld/1998/00000002/00000003/art00005", "children": [ { "text": " Does the efficacy of BCG decline with time since vaccination?.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "The international journal of tuberculosis and lung disease", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "2", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(3), 200-207.{/ref} {ref}Aronson, N. E., Santosham, M., Comstock, G. W., Howard, R. S., Moulton, L. H., Rhoades, E. R., & Harrison, L. H. (2004). ", "spanType": "span-simple-text" }, { "url": "https://jamanetwork.com/journals/jama/article-abstract/198681", "children": [ { "text": "Long-term efficacy of BCG vaccine in American Indians and Alaska Natives: a 60-year follow-up study.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "Jama", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "291", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(17), 2086-2091.{/ref} The reason for such variability is not clear, but factors such as different vaccine seed strains used for immunization and pre-existing immunity in people already exposed to other mycobacteria strains may be important.\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "Notably, BCG vaccine does not protect people from primary infections, that is it does not prevent people from getting infected with ", "spanType": "span-simple-text" }, { "children": [ { "text": "M. tuberculosis ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "bacterium in the first place. BCG also does not prevent activation of latent TB if a person has already been infected. Therefore, the vaccine has limited effect on prevention of ", "spanType": "span-simple-text" }, { "children": [ { "text": "M. tuberculosis ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "spread in a population.{ref} https://www.who.int/biologicals/areas/vaccines/bcg/en/ {/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Yellow fever vaccine", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart here shows the coverage of the yellow fever vaccine.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Yellow fever (YF)\u00a0is a viral disease transmitted by infected mosquitoes. There are 40 countries and territories at risk for yellow fever in Africa and the Americas and of these 36 include yellow fever vaccination in their routine immunization schedules. Total, vaccine coverage in 2018 was estimated at 49%.{ref}", "spanType": "span-simple-text" }, { "url": "https://www.who.int/news-room/fact-sheets/detail/immunization-coverage", "children": [ { "text": "https://www.who.int/news-room/fact-sheets/detail/immunization-coverage", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/yellow-fever-vaccine-coverage", "type": "chart", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Definitions and Measurement", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Calculating coverage", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The coverage is calculated as the proportion of persons in a target age group who received a vaccine dose. Dates of vaccination are either taken from a child\u2019s home-based record, recorded based on caregiver recall, or from health facility records.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "While appearing straightforward enough, several methodological problems of household survey respondent data on vaccination have been well documented.{ref}Daniel A. Salmon, Philip J. Smith, Ann Marie Navar, William K. Y. Pan, Saad B. Omer, James A. Singleton, Neal A. Halsey; Measuring Immunization Coverage among Preschool Children: Past, Present, and Future Opportunities, ", "spanType": "span-simple-text" }, { "children": [ { "text": "Epidemiologic Reviews", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", Volume 28, Issue 1, 1 August 2006, Pages 27\u201340, ", "spanType": "span-simple-text" }, { "url": "https://doi.org/10.1093/epirev/mxj001", "children": [ { "text": "https://doi.org/10.1093/epirev/mxj001", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Questions have arisen about how accurately parents can recall child immunization history and the limitations of phone calls to collect data.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Even accurately estimating target populations in low-income settings can be difficult and discrepancies have been found when comparing country-reported figures with independent surveys.{ref}\"Global childhood immunization coverage growing at only half the officially reported rate, IHME study\" online here: ", "spanType": "span-simple-text" }, { "url": "http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme", "children": [ { "text": "http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Furthermore, childhood vaccinations are rarely considered altogether. The DTP3 vaccination tends to be the vaccination most often used as a marker of strength in a country\u2019s immunization programs, since three administrations of the vaccination are required.{ref}Other vaccines measured by the WHO and UNICEF are HepB3, Hib3, MCV and PAB.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "National and subnational coverage", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "National coverage rates are what is focused upon, but even when national coverage are high, subnational coverage can reveal inequities, which is why the WHO and UNICEF are increasing efforts to gather high quality subnational coverage data.{ref}See:\u00a0\u00a0", "spanType": "span-simple-text" }, { "url": "http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/", "children": [ { "text": "http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In 2015 coverage estimates at the district level were only reported for 158 of the 194 WHO Member States. 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Also available via Gapminder ", "spanType": "span-simple-text" }, { "url": "http://www.gapminder.org/data/", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u00a0(search \"vaccine\" to find the data).", "spanType": "span-simple-text" } ], "parseErrors": [] } ], "parseErrors": [] }, { "text": [ { "text": "Further reading", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "More information about vaccines in general can be found on the World Health Organization (WHO) page on ", "spanType": "span-simple-text" }, { "url": "http://www.who.int/topics/immunization/en/", "children": [ { "text": "immunization", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "top": [], "type": "all-charts", "heading": "Interactive charts on vaccination", "parseErrors": [] } ], "type": "linear-topic-page", "title": "Vaccination", "authors": [ "Samantha Vanderslott", "Saloni Dattani", "Fiona Spooner", "Max Roser" ], "excerpt": "Vaccines are key in making progress against infectious diseases and save millions of lives every year.", "dateline": "May 10, 2013", "subtitle": "Vaccines are key in making progress against infectious diseases and save millions of lives every year.", "sticky-nav": [], "sidebar-toc": true, "featured-image": "Screen-Shot-2020-12-30-at-19.13.37.png" }, "createdAt": "2019-11-25T15:46:43.000Z", "published": false, "updatedAt": "2022-10-13T10:56:30.000Z", "revisionId": null, "publishedAt": "2013-05-10T23:14:52.000Z", "relatedCharts": [ { "slug": "were-flu-vaccines-available-in-the-country", "title": "Availability of flu vaccines", "variantName": null, "keyChartLevel": 2 }, { "slug": "covid-vaccinations-vs-covid-death-rate", "title": "COVID-19 vaccinations vs. COVID-19 deaths", "variantName": null, "keyChartLevel": 0 }, { "slug": 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2013-05-10 23:14:52 | 2024-02-24 00:30:09 | [ "Samantha Vanderslott", "Saloni Dattani", "Fiona Spooner" ] |
Vaccines are key in making progress against infectious diseases and save millions of lives every year. | 2019-11-25 15:46:43 | 2022-10-13 10:56:30 | https://ourworldindata.org/wp-content/uploads/2020/12/Screen-Shot-2020-12-30-at-19.13.37.png | {} |
This article was first published in July 2015; last revised in October 2022. **[See all interactive charts on vaccination ↓](#all-charts)** _We thank Stephanie Shendale, Sarah Loving, Anita Milicic, and Andy Pollard for helpful comments and suggestions on earlier draft versions of this entry._ ### Related writing * [Smallpox](https://ourworldindata.org/smallpox) — How has vaccination eradicated smallpox? * [Disease eradication](https://ourworldindata.org/eradication-of-diseases) — How and which diseases can be eradicated? * [Child & ](https://ourworldindata.org/pneumonia#pneumococcal-vaccines)[infant](https://ourworldindata.org/child-mortality#)[ mortality](https://ourworldindata.org/pneumonia#pneumococcal-vaccines) — What are children dying from and how can we prevent it? --- # Not every child who should be vaccinated is vaccinated --- ### Global vaccine coverage This chart shows the global vaccination coverage of one-year-olds with some of the most important vaccines recommended by the WHO. For many essential vaccines coverage is now much higher than 80%. However, the rates of vaccination are still not sufficient. If you click the play button you see that the coverage for most vaccines has increased substantially over time. The vaccine against diphtheria, tetanus and pertussis, is often used as the key metric for global vaccination coverage because it is a good indicator for access to routine immunization services. In 2018, coverage of the third dose of DTP was 86%. This means that out of 135 million under-one-year-olds more than 19 million did not receive full immunization. The coverage of the first dose of DTP was 90% indicating that **13.5 million children were not vaccinated** in 2018. In 2018, only 35% of children globally received the rotavirus vaccine, which protects children from [diarrheal diseases](https://ourworldindata.org/diarrheal-diseases) — [one of the leading causes](https://ourworldindata.org/child-mortality#what-are-children-dying-from) of child mortality. Similarly, pneumococcal vaccine that protects children from [pneumonia](https://ourworldindata.org/pneumonia) — the leading cause of child mortality — only reached 47% of one-year-olds.{ref}This and other numbers in this entry are based on the estimates by the World Health Organisation. The coverage estimates are calculated by dividing the total number of vaccinations given by the number of children in the target population. Target population size is usually based on census population projections. This means that there may be children in the target population that for medical reasons should be exempt from vaccination. These medical reasons may include factors such as allergies to vaccine components or severe immunodeficiencies. Notably, such cases are very rare and would have little effect on global coverage numbers. For example, [a study](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4783279/) from 2003 identified severe allergic reaction in only 0.000063% of all vaccinations, that's 0.63 cases per million vaccinations. In addition, vaccines are always being improved with fewer ingredients that may cause allergic reactions. Vaccination of children with immunodeficiencies generally needs to be assessed by a specialist. Especially, for vaccine that are based on a live pathogens. For example, [WHO recommends](https://www.who.int/immunization/policy/Immunization_routine_table1.pdf) vaccinating HIV-positive children with measles vaccine if child's HIV infection is asymptomatic or not severe. Similarly, children with severe immunodeficiency syndrome (SCID), a genetic disorder that causes defects in immune system, are [safely vaccinated](https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/severe-combined-immunodeficiency-scid) with many vaccines before SCID is even diagnosed, but it's recommended not to vaccinate them with live vaccines. In fact, one of the reasons it is important to increase vaccination rates is that those children and adults who for medical reasons cannot be vaccinated would still be protected from diseases through [herd immunity](https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity).{/ref} ### undefined undefined https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds?time=1980..2015 <Chart url="https://ourworldindata.org/grapher/global-vaccination-coverage"/> ### Prosperity and vaccination coverage Why do not all children in the world receive vaccinations? This chart shows that it is in poor countries where vaccination coverage is low. The vaccine coverage against diphtheria, pertussis (whooping cough), and tetanus is a good marker of the strength of a country’s immunization programs since several administrations are required. All rich countries have vaccination coverage rates of more than 90%. It is in low- and middle-income countries where coverage is low – in some countries below 50%. But the chart also shows that some poor countries – like Burundi, Rwanda, and Bangladesh – achieve high coverage rates. Similarly, countries in which a large share of the population is living in extreme poverty often – but not always – have lower immunization rates, as [this chart shows](https://ourworldindata.org/grapher/vaccination-coverage-dpt-by-extreme-poverty?endpointsOnly=0). <Chart url="https://ourworldindata.org/grapher/vaccination-coverage-by-income-in"/> --- # Vaccines save lives --- We know that vaccines save lives. But how many lives vaccines have they saved? The World Health Organisation (WHO) suggests that vaccination prevents 2-3 million deaths each year.{ref} [https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage](https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage){/ref} However, while we are certain that vaccines have saved millions of lives, calculating a precise number is impossible. Also the quoted number from the WHO is in important ways a very low estimate. The counterfactual world, in which vaccines would have never been developed, would be so different that an estimate of the impact of vaccines is impossible. One example that makes this clear is to consider the impact of the smallpox vaccine: [Smallpox](https://owid.cloud/smallpox) was once an extremely common and deadly infectious disease, but it has been eradicated globally back in 1977 thanks to the vaccination against the disease. It is impossible to know exactly how many people would die of smallpox today if scientists had not developed the vaccine. Reasonable estimates are in the range of around 5 million lives per year, which implies that between 1980 and 2018 around 150 to 200 million lives have been saved.{ref}UNICEF (1996) and Hinman, A. R. (1998) estimate that in the absence of a vaccine the world would have seen 5 million deaths due to smallpox every year in the mid-1990s. Assuming that the estimate for the mid-1990s provides a midpoint estimate for the period since 1980 and therefore multiplying the 5 million per year estimate by the number of years between 1980 and 2018 means that since the eradication of the disease 190 million people’s lives were saved. UNICEF (1996) – Vaccines bring 7 diseases under control. Online [here](https://www.unicef.org/pon96/hevaccin.htm).{/ref} This makes clear why it is so difficult to estimate the number of lives saved every year and why the WHO estimate is rather low. ## How vaccines work & herd immunity The basic mechanism by which vaccines work is simple: Vaccines create immunity in an individual by introducing a weakened or killed form of the pathogen that make us ill – such as bacteria or viruses – or its toxins or one of its surface proteins. The vaccine induces acquired immunity so that when your body encounters the real disease-causing agent it is ready to mount a defense. There is a collective social benefit in a high vaccination coverage. For most diseases, the greater the proportion of people who are immunized, the better protected is everyone in the population as the disease transmission can be reduced or stopped. Herd immunity is a community protection that is created when a high percentage of the population is vaccinated, such that it less likely that the infectious disease spreads.{ref}See Oxford's Vaccine Knowledge Project for an explanation here: [http://vk.ovg.ox.ac.uk/herd-immunity](http://vk.ovg.ox.ac.uk/herd-immunity).{/ref} Herd immunity provides a protective barrier, especially also for those who _cannot_ be vaccinated. These include vulnerable groups such as babies too young to be vaccinated or immune-compromised children who are the first potential victims of low vaccination rates. When a person is immune to a disease they can act as a barrier to slow down or prevent the transmission of disease to other people. When the number of people in a population that are immune against a disease is reached, such that a disease no longer persists in the population, this is called the _herd immunity threshold_ (HIT). The table shows the HIT for several diseases. Measles and pertussis are highly contagious airborne diseases and a larger share of people need to be vaccinated to stop the transmission. Because of this these diseases have the highest HIT rates that need to be reached. For example, two doses of measles vaccination offers 99% protection, while in the absence of immunization, the lifetime risk of infection is nearly 100%.{ref}Beutels P, Van Damme P, Van Casteren V, Gay NJ, De Schrijver K, Meheus A. _The difficult quest for data on "vanishing_"_vaccine-preventable infections in Europe: the case of measles in Flanders_ (_Belgium_). Vaccine. 2002 Oct 4;20(29- 30):3551-9 [here](https://www.ncbi.nlm.nih.gov/pubmed/12297401){/ref} ##### Herd Immunity Thresholds of vaccine-preventable diseases{ref}This table is taken from [Wikipedia's entry on Herd Immunity](https://en.wikipedia.org/wiki/Herd_immunity) – the original sources are listed there.{/ref} <div class="raw-html-table__container"><table><thead><tr><th scope="col" colspan="1">Disease</th><th scope="col" colspan="1">Transmission</th><th scope="col" colspan="1">Basic reproduction number</th><th scope="col" colspan="1">Herd Immunity Threshold</th></tr></thead><tbody><tr><td colspan="1" rowspan="1">Measles</td><td colspan="1" rowspan="1">Airborne</td><td colspan="1" rowspan="1">12–18</td><td colspan="1" rowspan="1">92–95%</td></tr><tr><td colspan="1" rowspan="1">Pertussis</td><td colspan="1" rowspan="1">Airborne droplet</td><td colspan="1" rowspan="1">12–17</td><td colspan="1" rowspan="1">92–94%</td></tr><tr><td colspan="1" rowspan="1">Diphtheria</td><td colspan="1" rowspan="1">Saliva</td><td colspan="1" rowspan="1">6–7</td><td colspan="1" rowspan="1">83–86%</td></tr><tr><td colspan="1" rowspan="1">Rubella</td><td colspan="1" rowspan="1">Airborne droplet</td><td colspan="1" rowspan="1">6–7</td><td colspan="1" rowspan="1">83–86%</td></tr><tr><td colspan="1" rowspan="1">Smallpox</td><td colspan="1" rowspan="1">Airborne droplet</td><td colspan="1" rowspan="1">5–7</td><td colspan="1" rowspan="1">80–86%</td></tr><tr><td colspan="1" rowspan="1">Polio</td><td colspan="1" rowspan="1">Fecal-oral route</td><td colspan="1" rowspan="1">5–7</td><td colspan="1" rowspan="1">80–86%</td></tr><tr><td colspan="1" rowspan="1">Mumps</td><td colspan="1" rowspan="1">Airborne droplet</td><td colspan="1" rowspan="1">4–7</td><td colspan="1" rowspan="1">75–86%</td></tr><tr><td colspan="1" rowspan="1">SARS</td><td colspan="1" rowspan="1">Airborne droplet</td><td colspan="1" rowspan="1">2–5</td><td colspan="1" rowspan="1">50–80%</td></tr><tr><td colspan="1" rowspan="1">Ebola</td><td colspan="1" rowspan="1">Bodily fluids</td><td colspan="1" rowspan="1">1.5–2.5</td><td colspan="1" rowspan="1">33–60%</td></tr><tr><td colspan="1" rowspan="1">Influenza</td><td colspan="1" rowspan="1">Airborne droplet</td><td colspan="1" rowspan="1">1.5–1.8</td><td colspan="1" rowspan="1">33–44%</td></tr></tbody></table></div> --- # Progress made with vaccination --- In total there are now at least 28 human diseases against which we have effective vaccines.{ref}Cholera, Dengue fever, Diphtheria, Haemophilus influenzae type b, Hepatitis A, Hepatitis B, Hepatitis E, Human papilloma-virus, Influenza, Japanese encephalitis, Malaria, Measles, Meningococcal disease, Mumps, Pneumococcal disease, Pertussis, Poliomyelitis, Rabies, Rotavirus gastroenteritis, Rubella, Tetanus, Tick-borne encephalitis, Tuberculosis, Typhoid fever, Varicella, Yellow fever, Shingles (Herpes Zoster), and Smallpox. See [https://en.wikipedia.org/wiki/Vaccine-preventable_diseases](https://en.wikipedia.org/wiki/Vaccine-preventable_diseases) and [https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/](https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/){/ref} The breakthrough that allowed us to get there was made in the late 18th century, the smallpox vaccine was the very first vaccine. ## Smallpox and the origin of vaccination Vaccination has a long history. An early form of vaccination was referred to as 'variolation' or more broadly as 'inoculation'. Practised for a long time in Asia, this was an ancient technique of deliberate [smallpox](https://owid.cloud/smallpox) infection in which dried smallpox scabs were blown up the nose to infect the person with a form of the disease which was often milder. By the 1700s variolation had spread to Africa, India and the Ottoman Empire, followed by the UK and America, where the method of infection more frequently used was a puncture to the skin. Variolation did work, but there were large risks. Those variolated could contract the more severe form of smallpox and die, and they could also transmit the disease to others. In 1796 English physician Edward Jenner demonstrated another method of inoculation in which he relied on cowpox. Cowpox is a similar disease to smallpox and it had previously been observed that an infection with cowpox can protect against smallpox. Jenner conducted an experiment using matter from a cowpox lesion to inoculate his gardener’s eight-year-old son James Phipps. Two months later Jenner exposed the boy to smallpox lesion matter and when Phipps did not develop smallpox he concluded that he was protected against the disease. Jenner called the procedure ‘vaccination’ after 'vacca' the Latin word for cow because of the origin of this first vaccination from the cowpox virus. Following the findings of Jenner as the first scientific attempt to control disease by vaccination, the smallpox vaccine went through many iterations, with the newer vaccines produced by modern cell culture techniques (passing the virus through cell culture makes the vaccine safer). By the middle of the 20th century confidence grew that smallpox could be the first disease that humankind might be able to eradicate. In 1967 the WHO launched a [global eradication of smallpox program](http://www.who.int/csr/disease/smallpox/vaccines/en/). Mass vaccination of over 80% of a country's population ensued but people who were nomadic or lived in politically unstable regions posed particular problems. A number of innovations came in the development of foot-powered injector called the [“ped-o-jet” and then the bifurcated needle](http://www.who.int/csr/disease/smallpox/vaccines/en/), which was efficient and cost-effective to use. In order to reach large sections of population, epidemiologist [William Foege](http://www.who.int/csr/disease/smallpox/vaccines/en/) developed Eradication Escalation (E2) to contain smallpox outbreaks during October (the seasonal low point of smallpox transmission where prevention of just few cases could stop a smallpox chain transmission). [Other obstacles faced](http://www.who.int/csr/disease/smallpox/vaccines/en/) included forcibly vaccinating an Indian religious leader to convince his followers to be vaccinated, negotiation of ceasefires for vaccine transport in war-torn Nigeria, vaccinating in concentric rings around an outbreak, and cash bounties to reward the reporting of smallpox cases. Finally in 1977 the last case of naturally contracted smallpox was reported in Somalia, in Ali Maow Maalin, and in 1980 the [WHO announced that smallpox had been eradicated](http://www.who.int/csr/disease/smallpox/vaccines/en/). We cover the history of smallpox, including the vaccination and eradication, in more detail in our entry on [smallpox](https://owid.cloud/smallpox). ## Vaccine innovation The chart here shows a timeline of innovation in the development of vaccines. Each bar begins in the year in which the pathogenic agent was first linked to the disease and the bar ends in the year in which a vaccination against that pathogen was licensed in the US. For some diseases there has been a relatively short timespan between when the infectious agent was linked to the disease and when a vaccine was developed. Before 2020 the quickest development was that for measles. The agent was linked to the disease in 1953 and the vaccine was licensed in the U.S. in 1963. In 2020 this record was broken when [several vaccines](https://owid.cloud/covid-vaccinations) were developed within just one year to fight the [coronavirus pandemic](https://owid.cloud/coronavirus). [Malaria](https://ourworldindata.org/malaria/) is proving harder as it has been over a century since the agent was linked to the disease. Alphonse Laveran discovered in 1880 that the Plasmodium parasite is the cause for malaria.{ref}See Francis EG Cox (2010) – History of the discovery of the malaria parasites and their vectors. In _Parasites and Vectors_. Online [here](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2825508/#!po=8.33333).{/ref} Early vaccines developed in the last several decades were insufficiently effective and until recently none of the scientific efforts led to a licensed vaccine. Recently there has been new hope for a malaria vaccine as we document in [the relevant section in our entry on malaria](https://ourworldindata.org/malaria#a-vaccine-against-malaria). Vaccine innovation has followed both scientific and political-economic developments: * Bacterial culture techniques which allowed the development of bacterial vaccines for diphtheria, tetanus, and pertussis in the early 1900s. * The first and second world wars prompted combined efforts by universities, governments, and private companies. * By the 1950s viral tissue culture techniques allowed the development of vaccines against [polio](https://owid.cloud/polio), measles, mumps, rubella, and varicella (chickenpox). * New technologies in molecular biology and advanced chemistry techniques have most recently led to vaccines against hepatitis B, influenza, and pneumococcus, which causes pneumonia and meningococus, which causes meningitis and septicaemia. <Image filename="Vaccination-innovation-chart.png" alt=""/> ## Progress against vaccine-preventable diseases in the US The visualization here shows the reduction in cases and deaths from vaccine-preventable diseases in the United States after the introduction of each vaccine. This data was published by Roush and Murphy (2007){ref}Roush and Murphy (2007) – Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155–2163. [here](https://www.ncbi.nlm.nih.gov/pubmed/18000199){/ref} and the data can be viewed in a table [here](https://ourworldindata.org/roush-and-murphy-2007-data/). For several diseases the US has achieved a 100% reduction of cases and deaths and for many other diseases the reduction is often very substantial as well. ##### Reduction of cases and deaths of vaccine-preventable diseases in the United States after the introduction of the vaccine.{ref}These data are taken from the research paper Roush and Murphy (2007) – Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155–2163 [here](https://www.ncbi.nlm.nih.gov/pubmed/18000199). The vaccines against the diseases up till ‘Tetanus’ were vaccines licensed or recommended before 1980. The vaccines against the last 5 diseases were only licensed or recommended between 1980 and 2005.{/ref} <Image filename="Vaccine_Reduction-of-Cases-and-Deaths.png" alt=""/> ### The development of the vaccine against measles and the history of measles in the US The introduction of a vaccine was not the only reason for progress against these diseases, as the visualization shows. The case-fatality rates of measles was falling in high income countries such as the US prior to the introduction of the vaccine in 1960 – this is best seen by switching from the linear to the logarithmic axis. Improved living conditions, nutrition, and medical advancements meant that contracting measles was less and less likely to be fatal. The rate of cases however was virtually unchanged until after the measles vaccine was introduced – as our visualization shows.{ref}See also 'Graphical proof that vaccines work (with sources)' in _Medium_ online [here](https://medium.com/@visualvaccines/graphic-proof-that-vaccines-work-with-sources-61c199429c8c). To account for such long-term changes, Roush and Murphy (2007) report data from the period shortly before the introduction of the respective vaccine. [here](https://www.ncbi.nlm.nih.gov/pubmed/18000199){/ref} A visualization showing the total number of cases and deaths can be seen [here](https://ourworldindata.org/grapher/measles-cases-and-death). <Chart url="https://ourworldindata.org/grapher/measles-cases-and-death-rate"/> ## Global decline in vaccine-preventable diseases The WHO estimates that [2 to 3 million deaths](http://www.who.int/mediacentre/news/releases/2017/infants-worldwide-vaccinations/en/) are prevented every year through immunization against diphtheria, tetanus, whooping cough, and measles.{ref}In our graphics and visualizations we rely on the _Institute for Health Metrics_ (IHME) ‘[Global Burden of Disease Study 2016](http://ghdx.healthdata.org/gbd-results-tool)’ estimates of child death rates from individual VPDs (compared with other causes), TB death rates across countries, and death rates from individual VPDs; this dataset extends back to 1990 and therefore provides a longer-term perspective on these changes over time. However, lack of estimates from the IHME on the role of vaccination in the prevention of deaths means we rely on WHO data for the number of deaths prevented each year through vaccination and the total amount of deaths VPDs are responsible for. The rates reported by the WHO and IHME are in a similar range but do differ slightly. WHO data on individual disease death rates can be found here: [http://www.who.int/gho/mortality_burden_disease/en/](http://www.who.int/gho/mortality_burden_disease/en/){/ref} Nonetheless, the WHO also estimates that VPDs are still responsible for [1.5 million deaths](http://www.who.int/mediacentre/commentaries/vaccine-preventable-diseases/en/) each year. In the chart we see the global number of deaths of children younger than 5 years per year from 1990 to 2017. The number of deaths which are wholly or partially preventable by vaccines are shown in color.{ref}Note that, as discussed later in this post, the role of vaccines in prevention varies between these causes of death. Measles, for example, has the capacity to be eliminated through vaccination. Diarrheal deaths, in contrast, cannot be eliminated through vaccination alone; hygiene, water services, and nutrition must also be prioritised.{/ref} The chart shows that the reductions in child deaths over this 25-year period were primarily achieved by a reduction of the number of deaths from vaccine-preventable diseases: The decline in causes which are not vaccine preventable has been modest, while the number of child deaths caused by diseases for which vaccines are available declined from 5.1 million deaths in 1990 to 1.8 million deaths 27 years later. <Image filename="Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019.png" alt=""/> Two vaccines are responsible for saving millions each year: ‘DTP’ against diphtheria, tetanus, and pertussis (whooping cough) and ‘MMR’ against measles, mumps, and rubella.{ref}Some countries only give measles vaccines combined with rubella (MR) or with varicella in addition (MMRV).{/ref} Before the measles vaccine was introduced in 1963, measles caused a large number of deaths globally, estimated at [2.6 million each year](http://www.who.int/mediacentre/factsheets/fs286/en/). Because about 86% of the [world population is immunized today,](http://www.who.int/mediacentre/factsheets/fs378/en/) the number of people killed by measles have been cut dramatically to an estimated 95,000 deaths in 2017. Tetanus and pertussis were also previously much bigger killers, with pertussis affecting especially children younger than 5 years and tetanus striking newborns ([killing an estimated 787,000 newborns](http://www.who.int/immunization/diseases/tetanus/en/) in 1988, compared with 49,000 in 2013). ### The way ahead However, the gains in global vaccination coverage have slowed down slightly in the last few years. The WHO estimates that [19.5 million infants](http://www.who.int/mediacentre/factsheets/fs378/en/) worldwide are still at risk of VPDs because they miss out on basic vaccines.{ref}Highlighted are 10 countries [where approximately 60%](http://www.who.int/mediacentre/factsheets/fs378/en/) of these infants live in: Angola, Brazil, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan, and South Africa.{/ref} In addition, all the recommended doses of a vaccine need to be received for it to be most effective. In the case of measles three vaccine doses are recommended. Even though an estimated 85% of children receive their first dose of the vaccine, [this drops to 64%](http://www.who.int/mediacentre/factsheets/fs378/en/) for the second dose.Therefore, it is not only lack of vaccination that is a problem, but it is under-vaccination that leads to deaths from VPDs. What then are the most deadly VPDs? Which diseases continue to kill the most people? ### The most deadly diseases **Tuberculosis:** Determining which are the most deadly VPDs requires acknowledging that some vaccinations are more effective than others. While most vaccines included in national routine schedules are highly effective, a better vaccine for tuberculosis (TB) is desperately needed. It is Sub-Saharan Africa and parts of Asia in particular that [are affected by TB](https://ourworldindata.org/grapher/tuberculosis-death-rates), as the world map shows. The vaccine for TB – Bacillus Calmette–Guérin (BCG) – has been in use for nearly 100 years. It protects against severe forms of TB but is [not effective against pulmonary TB](https://wellcome.ac.uk/news/world-immunisation-week-seven-vaccine-challenges) (in the lungs) and has variable effectiveness against TB in adults.{ref}Zwerling A, Behr MA, Verma A, Brewer TF, Menzies D, Pai M. The BCG World Atlas: A Database of Global BCG Vaccination Policies and Practices. _PLoS Medicine_. 2011;8(3):e1001012. doi:10.1371/journal.pmed.1001012. Available [here](http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001012).{/ref},{ref}For a detailed commentary on why we do not yet have an effective TB vaccine see: Davenne T, McShane H. Why don’t we have an effective tuberculosis vaccine yet?_ Expert Review of Vaccines_. 2016;15(8):1009-1013. doi:10.1586/14760584.2016.1170599. Available [here.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4950406/){/ref} Furthermore, resistance of antibiotics used to treat TB is increasing, meaning some people can no longer be cured by drugs. The estimated number of people in 2016 with [multi-drug resistant TB was 490,000](http://www.who.int/features/qa/79/en/). The fact that there is not a fully effective vaccine and that antibiotic treatment is facing serious difficulties makes TB the most deadly VPD. Meningococcal meningitis and hepatitis B are also deadly VPDs. **Meningococcal Meningitis: **Despite the introduction of _MenAfriVac_ in 2010, an effective vaccine against the most common type of meningitis in that region, meningococcal meningitis killed almost 130,000 people in 2016. Many cases occur in the so-called ‘meningitis belt’ of sub-Saharan Africa, crossing from Senegal to Ethiopia. Not all the countries in the meningitis belt have implemented mass vaccination campaigns for _MenAfriVac_ and also do not benefit from the expensive _MenACWY_ vaccine introduced into richer countries to protect against other types of meningococcal meningitis.{ref}An affordable _MenACWYX_ vaccine is being developed to cover all the types of meningococcal disease (with the exception of meningitis B, which is available through a separate vaccine) and will also have the ability to be transported at higher temperatures. It is currently in phase 1 clinical trial, with the hope that it will be available for use in 2020–2022.{/ref},{ref}See Meningococcal disease in the Middle East and Africa: Findings and updates from the Global Meningococcal Initiative, Borrow, Ray et al. _Journal of Infection_, Volume 75 , Issue 1 , 1 - 11. Available [here](http://www.journalofinfection.com/article/S0163-4453(17)30114-7/abstract).{/ref} **Hepatitis B:** The vaccine against hepatitis B is also very effective ([an estimated 95% effectiveness](http://www.who.int/mediacentre/factsheets/fs141/en/) in preventing disease), meaning increased vaccination could lead to a significant reduction in deaths. Still, global coverage of the hepatitis B vaccine is lagging. In 2015, while [84% coverage was reached](http://www.who.int/mediacentre/factsheets/fs141/en/) for the third dose of the vaccine, the coverage for the birth dose was only 39%. Estimates from mathematical models have shown that if infant coverage would reach 90%, and the first dose administered at birth, 84% of global hepatitis B-related deaths could be prevented.{ref}Susan T Goldstein, Fangjun Zhou, Stephen C Hadler, Beth P Bell, Eric E Mast, Harold S Margolis; A mathematical model to estimate global hepatitis B disease burden and vaccination impact, _International Journal of Epidemiology_, Volume 34, Issue 6, 1 December 2005, Pages 1329–1339, [https://doi.org/10.1093/ije/dyi206](https://doi.org/10.1093/ije/dyi206). Available [here](https://www.ncbi.nlm.nih.gov/pubmed/16249217).{/ref} ## Eradication of diseases through vaccination Eradication is the ultimate goal of vaccination against a disease. ### How do we eradicate diseases? One of the greatest successes that we can imagine for humanity is the complete eradication of a disease. For one human disease – smallpox – this has actually been achieved. The disease was fully eradicated in 1980. For other diseases we are getting close, as we show in our entry on the eradication of disease. https://owid.cloud/eradication-of-diseases ### On the way to the eradication of polio Polio is targeted for global eradication. This has become possible through the polio vaccine that was developed in 1955. The WHO estimates that in 2015, [85% of infants around the world](https://ourworldindata.org/polio/#polio-prevalence-in-the-developing-world-and-the-global-spread-of-the-polio-vaccine) received three doses of polio vaccine. And the number of paralytic polio cases have [decreased by over 99%](https://ourworldindata.org/polio/#the-number-of-reported-polio-cases-by-world-region) since the 1980s, from an estimated 350,000 to 400,000 paralytic cases per year to [22 reported cases in 2017](http://www.who.int/mediacentre/factsheets/fs114/en/). ### Polio We present the empirical evidence on the effort to eradicate poliomyelitis in an entry entirely dedicated to polio. https://ourworldindata.org/polio/ ### Eradication of smallpox While the benefits might possibly be forgotten as vaccine-preventable diseases have lost their threat thanks to the introduction of the vaccines it is still true that people around the world – including those in richer countries – continue to benefit from vaccinations. One of the greatest successes of global health is eradication of smallpox. Smallpox, which just decades ago killed several hundred thousand people every year was successfully eradicated in 1980 thanks to the global vaccination program.{ref}Smallpox is the only disease that affects humans which has been eradicated through vaccination. Rinderpest, a disease that affected cattle, has also been eradicated. Polio is getting close to being eradicated.{/ref} ### Smallpox You find more detail about the disease and its eradication in our entry on smallpox. https://owid.cloud/smallpox --- # Public support and skepticism --- ## People do not know how well we actually do in global vaccination Today vaccines protect millions of people around the world from infectious diseases. In this fight we are much, much further ahead than most people realize. The first chart shows the evidence for this misperception. In this chart we plotted the survey responses that people gave when they were asked _“How many of the world’s 1-year old children today have been vaccinated against some disease?”_. The correct answer was 85.8%; this is the share of 1-year olds that received the third dose of the combination vaccine that protects against Diphtheria, Tetanus, and Pertussis (whooping cough). But in all countries in which people were surveyed people were much too pessimistic about the global coverage. Americans think that only 35% of the world's children are vaccinated, the true coverage is 50 percentage points higher.{ref}This survey result is in line with the finding of the _Gapminder Ignorance Project_, which studied Americans' perception of global vaccination efforts. Just as in the Ipsos Mori survey, the answers that most Americans gave were far off from the truth. <Image filename="Ignorance-Test_Global-Measles-vaccination-coverage.png" alt=""/> More information on the Gapminder 'Ignorance Test' can be found [here](http://www.gapminder.org/ignorance/). The results for the US are [here on Gapminder's site](http://www.gapminder.org/news/ignorance-survey-in-the-usa-2013/). {/ref} In Japan people were even more pessimistic and thought that only 18% were vaccinated. As it is often the case in questions on global development we again see that people in poorer countries have a [more accurate view of the world](https://owid.cloud/wrong-about-the-world): in Kenya and Senegal people thought that vaccines reach around two thirds of all children in the world, but even these highest estimates are 20 percentage points too low. ##### We hugely underestimate global vaccination coverage{ref} The survey results are from Chris Jackson (2017) – Global Perceptions of Development Progress: ‘Perils of Perceptions’ Research’, published by Ipsos MORI, 18 September 2017. Online [here](https://www.ipsos.com/en/global-perceptions-development-progress-perils-perceptions-research).{/ref} <Image filename="Misperception-of-global-vaccination-coverage.png" alt=""/> ### People’s view on vaccination coverage is outdated by more than three decades The chart here illustrates how outdated people's answers are. Most individuals think that the global vaccination coverage today is as low as it was in the 1980s or even earlier.{ref} **Terminology: _vaccination_ and _immunization_** There is a technical difference between vaccination and immunization, as the National Health Service (NHS) [explains](http://www.shb.scot.nhs.uk/board/publichealth/immunisation.asp): “Vaccination means having a vaccine – that is actually getting the injection, or nasal spray or oral vaccine. Immunization means both receiving a vaccine and then becoming immune to a disease”. The distinction is made because in a very small number of those who are vaccinated the vaccination will not ‘take’ and therefore that vaccinated person will not be immunized (i.e. will not be immune to the disease). However, as this refers to a very small number of people both terms are often used interchangeably across the academic literature and in media reporting and we follow this convention in this entry.{/ref} The World Health Organization recommends routine vaccinations to prevent illness, death and disability from diseases including diphtheria, pertussis (whooping cough), tetanus, polio, measles, and hepatitis B.{ref}For the WHO recommendations see [http://www.who.int/ith/vaccines/en/](http://www.who.int/ith/vaccines/en/) The Bacille Calmette-Guerin (BCG) vaccine for tuberculosis (TB) is recommended in countries where TB is common. BCG policies and practices have varied considerably across time and countries. The [BCG World Atlas](http://www.bcgatlas.org/) is an online resource that tracks these changes comprehensively.{/ref} We have created a [chart](https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds) that shows the absolute number of one-year-olds who have received the vaccinations. Where the biggest gap in vaccination lies is with all children being fully vaccinated and protected as much as possible from infectious diseases. Gavi, the Vaccine Alliance, has analysis that suggests only [7% of infants in the 73 poorest countries are fully immunized (that is, receiving all doses of all recommended vaccines)](https://www.nature.com/articles/d41586-017-05923-8). ## How many people support vaccination across the world? The London-based research charity _The Wellcome Trust_ published their [Wellcome Global Monitor](https://wellcome.ac.uk/what-we-do/our-work/wellcome-global-monitor) in 2019 on attitudes to science and major health challenges. It is the world’s largest study of its kind, surveying over 140,000 people from over 140 countries. As part of the _Gallup World Poll_, the 30-question survey ran during 2018.{ref}It provides data on topics such as trust in science and scientists; trust in sources of information about health; public understanding of the word ‘science’; the intersection between religious teachings and science; and attitudes to vaccines. In this post, we focus on how attitudes to vaccination vary across the world.{/ref} The Wellcome Trust survey asked three core questions related to attitudes to vaccines: do people think that vaccines are important for children to have; do they think vaccines are safe; and do they believe vaccines are effective. ### Most people in the world think vaccines are important for children to have More than 9-in-10 people in the world (92%) think that vaccines are important for children to have. How support varies across the world is shown in the map. We see high support for vaccination across almost all countries. In most countries over 80% of respondents think child vaccination is important, in many countries it is over 90% who think so. There is a visible North-South divide in attitudes: support is highest across South Asia at 98%; 97% in South America; 94% in Northern Africa; and 92% in Southern Africa. Support is still high, but lower across North America (87%); Western Europe (83%) and Eastern Europe (80%). Of those surveyed in Venezuela, Palestine, Ethiopia and Northern Cyprus thought vaccines were most important: 100% were in favour.{ref}This is a stark result for Venezuela in particular (although perhaps unsurprising) since the availability and coverage of child vaccination [has fallen significantly](https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1) over the last few years.{/ref} <Chart url="https://ourworldindata.org/grapher/share-agrees-vaccines-are-important-wellcome"/> ### Most people in the world think vaccines are safe, but mistrust is high in some countries Some parents may not agree for children to be vaccinated if they think vaccines are unsafe or could potentially cause side-effects which are worse than the benefits. How prevalent are these safety concerns? Globally, a small share of people disagree that vaccines are safe. Only 7% of respondents across the world said they “strongly disagree” or “somewhat disagree” with the statement ‘Vaccines are safe’. In many countries these concerns are very low: in Bangladesh, for example, less than 1% disagree that vaccines are safe. In neighbouring India, only 2% disagree. We see this distribution across the world in the map. Trust in vaccines is not high everywhere. There are some clear outliers. The French were most skeptical: 1-in-3 disagreed that vaccines were safe. Many in neighbouring Switzerland and Belgium were also very skeptical: more than 20% disagreed. Other countries with high mistrust of vaccine safety were Gabon (26%); Togo (25%); Russia (24%); Austria (21%), and Iceland (21%). <Chart url="https://ourworldindata.org/grapher/share-disagree-vaccines-are-safe-wellcome-trust"/> ### Only 5% of respondents globally disagree that vaccines are effective but skepticism is much higher in some countries In response to the statement ‘Vaccines are effective’, only 5% of respondents across all surveyed countries said they “strongly disagree” or “somewhat disagree”. The vast majority of people do not think of vaccines as ineffective. But, as with the other surveyed questions, this varies significantly across countries. We see this in the map. In some countries, very few respondents disagreed: less than 1% in Bangladesh and Egypt; 2% in India and Ethiopia; and 3% in China, Germany and the UK. Liberia is most skeptical with 28% disagreeing that vaccines are effective. But skepticism was also high in France (18%); Namibia (16%); Nigeria (16%); and Peru (15%). <Chart url="https://ourworldindata.org/grapher/share-disagrees-vaccines-are-effective"/> ### In some countries many people are undecided on vaccination The finding of the Wellcome Trust of mostly very positive attitudes towards vaccines – a health intervention that [saves millions of lives](https://ourworldindata.org/vaccination#how-is-the-world-doing-in-its-fight-against-vaccine-preventable-diseases) and [eradicated one of the worst diseases](https://ourworldindata.org/smallpox) humanity ever faced – is a very positive finding. But there is a concerning finding which is hidden when we look only at agreement and disagreement to the questions in the Global Monitor. Take Japan as one example. Only 66% of Japanese respondents thought vaccines were important for children to have – very low in comparison to other countries. But few disagreed that vaccines were safe (only 8%) and disagreed that they’re effective (only 3%). If few people thought they were unsafe and ineffective, why would support for vaccines be so low? Many Japanese respondents did not answer either way. 28% answered “neither agree nor disagree” to [whether child vaccination is important](https://ourworldindata.org/grapher/share-neither-agrees-disagrees-vaccines-important); 55% to the question regarding the [safety of vaccines](https://ourworldindata.org/grapher/share-neither-agree-disagree-vaccines-are-safe); and one-third were undecided on their effectiveness. It's difficult here, without further questions, to fully interpret the opinions of those in this undecided category: maybe they had no opinion; or they thought vaccines could be safe or effective in some cases, but not all; or some vaccines were safe but others were not. With this data, it's impossible to fully understand their reasoning. This stance was common across several other countries, as we see in the map. <Chart url="https://ourworldindata.org/grapher/share-neither-agrees-nor-disagrees-vaccines-effective"/> While being undecided or divided is perhaps less concerning than denialism on the importance, safety and effectiveness of vaccination, it nonetheless suggests that many are unaware of the massive role vaccines have played in [eradicating diseases](https://ourworldindata.org/vaccination#eradication-of-diseases-through-vaccination), and [saving lives across the world](https://ourworldindata.org/vaccination#diseases-preventable-through-vaccination). The success story of vaccines is one we don’t tell often enough. It’s also true that people in the 'neither' group may be more likely to be convinced by arguments that are put forward by those who deny the safety, effectiveness and importance of vaccination. In a [**related post**](http://ourworldindata.org/vaccine-skepticism) we take a look at why denialism around vaccination exists, and what is effective in addressing it. ## Does vaccine skepticism affect immunization coverage? The crucial question to ask when considering the importance of vaccine skepticism is: does it actually have an effect on behaviour? Does it really affect the share of children who are vaccinated? In the chart we see the comparison of vaccination rates – here as the share of children who were immunized against diphtheria, pertussis and tetanus (DTP) in 2015, the latest year available – to the share of respondents in a given country who disagreed that vaccines are safe. You can also [see this relationship](https://ourworldindata.org/grapher/immunization-measles-vs-vaccine-safety) for measles vaccine coverage. Overall we see that widespread public concern for vaccine safety does not appear to be strongly correlated with vaccination rates. While one-third of the French public disagrees with their safety, 97% of children in France are vaccinated. There are numerous other reasons, however, why vaccination rates in some countries are low: in low-to-middle income countries the availability, affordability and access to vaccines can be poor. Having low coverage rates often doesn’t reflect the population’s view of them. As the chart shows, in many poor countries the situation is the opposite as in France: the vast majority of the population considers vaccine safe, but only about every second child receives the DTP vaccine. One country which stands out is Ukraine: there we see that vaccination rates are uncharacteristically low for [its income level](https://ourworldindata.org/grapher/gdp-per-capita-worldbank) – less than 1-in-4 children receive the DTP vaccine. Skepticism of vaccine safety in Ukraine is high at 15%. Is there evidence that skepticism is reflected in cases and deaths from vaccine-preventable diseases? Over the last few years there has been [a reported rise](https://www.who.int/csr/don/06-may-2019-measles-euro/en/) in the number of measles cases in countries which had previously been close to eliminating the disease. In Europe, for example, there were more than [34,000 cases of measles](https://www.who.int/csr/don/06-may-2019-measles-euro/en/) in the first two months of 2019 alone. Ukraine [accounted for the majority](https://www.who.int/csr/don/06-may-2019-measles-euro/en/) (more than 70%) of these cases. And here as well as in Albania and Romania some measles cases led to the death of children. <Chart url="https://ourworldindata.org/grapher/perception-of-the-safety-of-vaccines-vs-vaccine-coverage"/> The visualization shows the relationship between the share of people who trust doctors and nurses in their country and share who disagree that vaccines are safe. Overall we see that countries with higher levels of distrust in the safety of vaccines tend to also have less trust in health professionals. There are however some outliers: France has relatively high trust in health staff, but are most mistrusting of vaccine safety. Health officials are worried that skepticism of vaccination will begin to translate to lower vaccination rates. One reason being attributed to higher skepticism is the spread of misinformation on social media. Social media firms do have a responsibility for dealing with misinformation and need to consider how to react carefully. Currently, social and online media companies are being asked by politicians in the US and UK to ban or control anti-vaccination messaging. Banning or strict control could reduce the exposure to such messages but does not solve the root problem: the public are asking questions about vaccines and are looking to find answers online. A worry is that banning certain sorts of information and groups will fuel suspicion and only drive activity elsewhere. Nonetheless, demands on social media firms to act is increasing. A request for action by [Adam Schiff to the CEOs of Google and Facebook](https://schiff.house.gov/news/press-releases/schiff-sends-letter-to-google-facebook-regarding-anti-vaccine-misinformation) sparked a cascade of responses. In an open letter, he asked for action against vaccine misinformation and similar demands have been made since, from the UK Health Secretary Matt Hancock among others. <Chart url="https://ourworldindata.org/grapher/trust-healthcare-vs-vaccine-safety"/> --- # Vaccine policy --- ## What determines if vaccinations are compulsory? Countries vary in whether vaccination is compulsory, mandatory (required according to specific mandates), or voluntary. Navin and Largent (2017) provide a helpful distinction between these policies. A compulsory policy is when refusing vaccination is illegal, while mandatory vaccination when certain goods and services are limited for not vaccinating.{ref}Navin M. Largent, improving non-medical exemption vaccine policies: three case studies. Public Health Ethics. 2017; 10: 225–234. Available [here](https://philpapers.org/rec/NAVINV){/ref} Which policy is followed has depended much on historical legacy, which becomes clear when one considers some of the different regulations and their history around the world: _Compulsory vaccination:_ Many Eastern Bloc countries introduced compulsory vaccination during the communist era. Vaccination was previously compulsory in Romania for example and after a drop in vaccination rates the country is going through the process of reintroducing compulsory vaccination. The same is true for Italy and also France, which had compulsory vaccination for three diseases but increased this number to 11 in January 2018 in response to a drop in vaccination rates. _Mandatory vaccination:_ Some countries, such as the United States, have mandates for vaccination where a child is required to be vaccinated to enter state school or daycare. An early case in the US paved the way for state jurisdiction to protect public health in light of personal liberty.{ref}See: [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/){/ref} In Jacobson v. Massachusetts (1905) the Supreme Court ruled that states have the authority to require vaccination against smallpox during a smallpox epidemic. Since then the US has had a history of school vaccination requirements. The increased number of children in public schools as a result of the compulsory school attendance law led to an increased risk of smallpox outbreaks, through close contact in large crowded classrooms.{ref}Stern, M., Alexandra. (2010). Better Off in School: School Medical Inspection as a Public Health Strategy During the 1918-1919 Influenza Pandemic in the United States{/ref} Similarly in Australia two policies penalize parents for not vaccinating their children. The 'No jab no play' policy removed unvaccinated children from state-sponsored childcare. The 2016 'No jab no pay' policy removes state welfare by not providing the universal 'Family Allowance' welfare payments for parents who are conscientious objectors of vaccination. _Voluntary vaccination:_ Some countries where vaccination is voluntary had early pushback against vaccination, as in the UK and the Netherlands. In 1853 a law was passed in England and Wales requiring universal vaccination against smallpox, but opposition from anti-vaccinationists led to laws being passed to allow for conscientious objection.{ref}Amin, A.N.E., Parra, M.T., Kim-Farley, R. et al. (2012) – Ethical Issues Concerning Vaccination Requirements. In _Public Health Reviews_ (2012) 34: 14. [https://doi.org/10.1007/BF03391666](https://doi.org/10.1007/BF03391666). Online here: [https://link.springer.com/article/10.1007/BF03391666](https://link.springer.com/article/10.1007/BF03391666){/ref} _Vaccination requirements for country entry:_ For countries in Africa and South America where yellow fever is endemic or where the mosquito vector is present a certificate of proof of vaccination is required. Only then will the country issue a visa upon entry to that country to prevent importation of this disease (particularly if travellers come from, or have visited other yellow fever endemic areas).{ref}See: [http://www.who.int/csr/ihr/icvp/en/index.html](http://www.who.int/csr/ihr/icvp/en/index.html){/ref} In past centuries (17th to 19th), yellow fever was transported to North America and Europe, causing large outbreaks that disrupted economies and development, and in some cases decimated populations. Throughout the 18th and 19th century, yellow fever was among the most feared diseases in the ports of the Old and New World. Saudi Arabia is the only country that requires the [additional vaccinations of meningococcal disease and polio](http://www.who.int/ith/updates/20170408/en/) for pilgrims visiting Mecca. ### Does it work to make vaccinations compulsory? Whether compulsory vaccination results in improved vaccination rates is not a straightforward question to tackle because it is highly dependant on country context, historical circumstance, cultural and social norms, as well as the practicalities of implementing and enforcing such a law. Certainly in [Eastern Bloc countries](https://theconversation.com/despite-scepticism-europe-has-high-vaccination-rates-but-it-shouldnt-be-complacent-75169) when the vaccination law was compulsory, vaccination rates have been high but it is unclear whether to attribute this to the law or the behaviours and mechanisms of compliance under communist rule. Certain vaccinations have historically been compulsory such as smallpox, polio, and yellow fever. Here vaccination rates have also been high but it also encouraged organised opposition to vaccination and public discontent. This is a major concern for public health authorities that a relationship of trust, between governments and citizens is threatened (particularly for health where a rhetoric of self-responsibility, personalisation, and choice is encouraged). There are countries with high vaccination rates without compulsory vaccination and governments do not want to disrupt public trust and self-responsibility by making vaccination compulsory, particularly if it is not seen as needed. It has been argued that high coverage has been achieved through "other approaches or efforts" and so acceptance of compulsory vaccination might be problematic in countries such as Sweden, Norway, Denmark, the Netherlands, and the UK.{ref}Salmon, Daniel A et al., Compulsory vaccination and conscientious or philosophical exemptions: past, present, and future, The Lancet, Volume 367, Issue 9508, 436 - 442{/ref} In recent years governments have acted in response to epidemics to make vaccinations compulsory, as we have seen for 2017-18 with compulsory vaccinations in France, Italy, Germany, and Romania. One country where we can see the effect of variation in vaccination policy is the US. In the US states decide what vaccine exemptions are permitted for children who receive education in schools or use daycare. Public schooling unfortunately means that schools are sites of epidemics for childhood diseases, which is the reason such vaccination laws are required. In individual states exemptions are granted for medical reasons but many states also allow for philosophical, personal belief or religious exemptions. Only three states – Mississippi, West Virginia, and California – only allow for medical exemption. [Californian immunization rates have increased](https://ourworldindata.org/app/uploads/2017/11/Screen-Shot-2017-11-10-at-15.31.35.png) following a new Senate Bill SB 277 in 2015 to remove non-medical exemptions to vaccination. The chart here shows vaccination coverage and what exemptions are allowed for each state. Fewer exemptions generally mean higher vaccine coverage. Indeed, Mississippi does often top the list as having the highest vaccination rates because only medical exemptions are allowed in the state. But starkly, Mississippi residents are also consistently the [unhealthiest](http://www.businessinsider.de/unhealthiest-states-in-the-us-health-rankings-2017-12?r=US&IR=T) and [poorest](https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/) in the entire country. Health outcomes are very poor and many residents cannot afford healthcare ([the state has the highest percentage without health insurance in 2017](https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/)). So perhaps it is unsurprising that residents accept subsidized vaccinations that are required for access to childcare and state schools. ##### Vaccination coverage of children, by US state in 2016/17{ref}The data source for vaccination coverage: School Vaccination Assessment Report, 2016-17 school year. Estimated vaccination coverage with 5 doses of Childhood Diphtheria toxoid, Tetanus toxoid, acellular Pertussis (DTaP) vaccination for kindergartners (typical age range is 4–6 years). The data source for exemptions is: Immunization Action Coalition, "Exemptions Permitted for State Immunization Requirements," 2017; LexisNexis; StateNet 2017 Regarding the school vaccination coverage and exemption methods the source notes: "Each school year, school nurses, other school personnel, or health department personnel check the vaccination and exemption status of kindergartners enrolled in public and private schools as required by state law or regulation. State and local immunization programs measure vaccination coverage among children entering kindergarten annually. This may be done for every student or for a sample of students. State and local areas set the vaccination requirements. Immunization information systems (IISs) may be used as one source of data for school vaccination assessment. The school-level data are reported to the health department. The aggregate data are reported to CDC for public and private schools. Data for home-schooled students are not routinely reported to CDC." The types of permitted exemptions vary by state. For specific details refer to [School Vaccination Requirements and Exemptions](https://www.cdc.gov/vaccines/imz-managers/coverage/schoolvaxview/requirements/index.html).{/ref} <Image filename="DTP-Vaccination-rate-by-US-State-and-exemption-status-1.png" alt=""/> ## Vaccine supply Supply constraints have caused problems for country access to vaccination. One-third of 194 countries have run out of a vaccine for a month or longer – according to [data](http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health) submitted to WHO and UNICEF – and this includes both high- and low-income countries. In the US, the Centers for Disease Control and Prevention (CDC) [stated](https://www.cdc.gov/vaccines/hcp/clinical-resources/shortages.html) that reasons for shortages were multi-factoral and included "...companies leaving the vaccine market, manufacturing or production problems, and insufficient stockpiles". In 2018, it [was reported](http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health) that shortages where supplies of vaccines were critically low included those that target yellow fever, hepatitis B, cholera, meningitis C, diphtheria, whooping cough, tetanus, hepatitis A, and tuberculosis. Concerns about the supply of vaccines in an epidemic or pandemic have been raised. For example, the supply of yellow fever vaccine was limited for the outbreak in Angola in 2016 leading to the recommendation of a fractional dose to extend existing supplies.{ref}See the WHO [here](http://www.who.int/emergencies/yellow-fever/mediacentre/qa/en/).{/ref} [Laurie Garrett argues](http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health) that because the drug had become so cheap (60 cents for each vaccine 2008) few companies had an incentive to produce it and world stocks of the vaccine were nearing zero, forcing the WHO to dilute donated vaccines from countries like Brazil (which sent 18 million doses) by 5 to 1 with the hope they would still be sufficiently effective. Romania experienced a situation of parallel vaccine exports in 2016 where more vaccines were exported than was supplied to meet the country's needs. A shortage of the measles, mumps, and rubella (MMR) vaccine was partly responsible for the measles outbreak in 2016-17.{ref}See [here](https://www.euractiv.com/section/health-consumers/news/romania-cuts-vaccine-exports-as-measles-outbreak-takes-hold/).{/ref} In Venezuela, a country experiencing an economic crisis, there are severe [shortages of medicines, including vaccines](https://www.bbc.co.uk/news/resources/idt-sh/Venezuela_bridge), which has led to an [estimated one million](https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1) unvaccinated children and the re-emergence of diseases such as diphtheria and measles. ## The cost of vaccines There are five big pharmaceutical companies{ref}According to MacKenzie, D. (2011) – Vaccines enjoy a healthy return. _New Scientist_. Available [online](https://www.newscientist.com/article/dn20877-vaccines-enjoy-a-healthy-return/).{/ref} that account for 80% of vaccine production: Sanofi Pasteur, GlaxoSmithKline, Merck, Pfizer, and Novartis.{ref}In 2014 their vaccine business was acquired by GlaxoSmithKline, as reported [here](https://www.telegraph.co.uk/finance/newsbysector/pharmaceuticalsandchemicals/11444023/GSK-and-Novartis-complete-deals-to-reshape-both-drugmakers.html).{/ref} Many vaccines are only provided by one or two suppliers. For newer vaccines there are often particularly few suppliers due to the high investment needed to develop a vaccine.{ref}There are exceptions however. A vaccine for tetanus and diphtheria (td) for example, has a large number of suppliers (13, and 7 for the paediatric formulation).{/ref} As one would expect from competition, the WHO reports that when vaccines are produced by a greater number of suppliers it leads to a decline of the prices of those vaccines.{ref}Review of vaccine price data. Submitted by WHO European Region Member States through the WHO/UNICEF. Joint Reporting Form for 2013. Online [here](http://www.euro.who.int/__data/assets/pdf_file/0009/284832/Review-vaccine-price-data.pdf?ua=1).{/ref} In the past vaccines were often viewed as less profitable products for pharmaceutical companies, which led to a lack of investment and some companies pulling out of production altogether.{ref}The Economist. (2010). A smarter jab. Available [online](http://www.economist.com/node/17258858#print){/ref} But this has changed as the revenue of the global vaccines market has increased and richer country governments and insurance companies have been willing to pay more for new vaccines. In addition, growing economies such as India and China are investing more in vaccines as well as developing their domestic manufacturing capacity. Poorer countries now have Gavi to help governments pool resources and make advance purchase commitments.{ref}The Economist. (2010). A smarter jab. Available [online](http://www.economist.com/node/17258858#print){/ref} Gavi is an international organisation created in 2000 to bring together public and private sectors, with the goal of equal access to new and underused vaccines for children in poorer countries. It subsidizes vaccines that otherwise would not be affordable for low-income countries. In addition to subsidizing vaccines themselves, Gavi offers [vaccine introduction grants](https://www.gavi.org/about/programme-policies/health-system-and-immunisation-strengthening-support-framework/), which help to cover the costs of introduction of new vaccines into routine immunization schedules. The map here shows which countries are eligible for GAVI support. <Chart url="https://ourworldindata.org/grapher/gavi-supported-countries"/> Some vaccines still remain expensive. For example, the pertussis vaccine is available in two versions: whole cell (wP) containing the whole pertussis bacterium or acellular (aP) which contains a part of the pertussis bacterium. The pertussis vaccine is often combined with diphtheria and tetanus to produce either a DTwP or DTaP vaccine.{ref}See WHO guidance for more information at: [https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf](https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf){/ref} DTaP is slightly more expensive; it is sometimes called 'the painless vaccine' because it causes less of a local reaction and pain but should not be given to children over the age of seven. However, DTwP has been shown to be more efficacious at preventing the transmission and spread of disease to unvaccinated people and to those with weak immunity. New vaccines tend to be more expensive as they are under patent protection. For example when the HepB vaccine was developed many lower income countries could not afford to pay $30 per dose.{ref}Jaffe, A. B., Lerner, J., Stern, S., & National Bureau of Economic Research. Innovation Policy and the Economy Group. (2006). _Innovation policy and the economy_. MIT Press. [here](https://books.google.co.uk/books/about/Innovation_Policy_and_the_Economy.html?id=9I7KowFvI9oC&source=kp_cover&redir_esc=y){/ref} Today there is often a differentiation between the prices paid by countries as shown in the small table. ##### Price differences for vaccines between the US and developing countries{ref}The source of the data is the [International drug price indicator guide](http://mshpriceguide.org/en/home/){/ref} <div class="raw-html-table__container"><table class=""><tbody><tr><td><strong>Vaccine</strong></td><td><strong>Cost per dose in a developing country</strong></td><td><strong>Cost per dose in the US</strong></td></tr><tr><td>HepB</td><td>$0.58 - 13.20</td><td>$50 - 100</td></tr><tr><td>BCG</td><td>$0.16 - 1.11</td><td>$100 - 200</td></tr><tr><td>Yellow fever</td><td>$4.30 - 21.30</td><td>$50 - 100</td></tr></tbody></table></div> ## Which countries include vaccines in their immunization schedules? Several vaccines, including rubella, mumps, and rotavirus, are included in immunization schedules in many countries around the world. This means these vaccines are provided and recommended through routine services. This doesn't necessarily tell us how many children _receive_ these vaccines in each country. The vaccines may or may not be mandatory and their coverage rates may vary widely. Similarly, when countries do not have a vaccine in their schedule, this does not mean that the vaccine is completely unavailable in those countries, as it may be optional or available commercially. In the chart you can see which countries include rubella vaccines in their national immunization schedules. Rubella vaccines became available for the first time in 1969, starting in the United States, where it was developed.{ref}Lanziera, T., Haber, P., Icenogle, J. P., & Patel, M. (n.d.). Rubella. In _Epidemiology and Prevention of Vaccine-Preventable Diseases_. Communication and Education Branch, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention.[ https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html](https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html){/ref} It was included in the schedules of the United States and most European countries as early as 1994 (the first year of this dataset). Over time, more countries included it in their schedule. But this took many years for some countries: for example, it took until 2018 for it to be included in countries such as Uganda and Congo. As of 2021 some countries, such as Nigeria and South Africa, still do not include it in their schedules.{ref}World Health Organization. (2021). _New and underutilized vaccines introduction_.[ https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html](https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html){/ref} In the links below, you can see these charts for other vaccines. <Chart url="https://ourworldindata.org/grapher/rubella-vaccine-immunization-schedule"/> ## Why do vaccine schedules differ? ### The chickenpox example Chickenpox (varicella) is an example of a vaccine that some countries adopt into their routine childhood vaccination schedules, while others do not. The question that follows is why there is a difference in opinion for introducing widespread uptake of a vaccine or not. Japan was one of the first countries to adopt universal chickenpox vaccination.{ref}Bonanni et al. 2009; Bonanni P., Breuer J., Gershon A., Gershon M., Hryniewicz W., Papaevangelou V., et al. (2009) – Varicella vaccination in Europe - taking the practical approach. BMC Med 7: 26 [here](https://www.ncbi.nlm.nih.gov/pubmed/19476611).{/ref} Australia, Canada, Germany, Qatar, Republic of Korea, Saudi Arabia, Taiwan, Uruguay, U.S., Italy (Sicily only) and Spain (Madrid only) followed afterwards and adopted universal chickenpox vaccination. When extreme cases of chickenpox have occurred there have been calls for the vaccine to become [available for free](http://www.bbc.co.uk/news/uk-england-cambridgeshire-36952432) through the National Health Service in the UK. However, most European countries do not vaccinate against chickenpox, except for 'at risk' groups. The main reason for not adopting universal vaccination is the high cost. Additional supporting justifications are that it is usually a [mild disease](http://www.nhs.uk/chq/Pages/1032.aspx?CategoryID=62) and the benefit of fewer cases of shingles – as explained [here](https://theconversation.com/everything-you-need-to-know-about-chickenpox-and-why-more-countries-dont-use-the-vaccine-63473). The Centers for Disease Control and Prevention in the US ran the [Varicella Active Surveillance Project](https://www.cdc.gov/chickenpox/surveillance/vasp.html) (VASP) from 1995 through to 2010 to monitor the impact of the varicella vaccination program and the key finding is shown in the chart. The coverage of the vaccine in Los Angeles County rose from 37.9% in 1997 to 95.1% in 2010, and in Philadelphia from 41.2% in 1997 to 94.6% in 2010 (one-dose vaccinations for children between 19 and 35 months of age). By 2010, varicella incidence declined by 98% in Antelope Valley (California) and West Philadelphia (Pennsylvania) compared with 1995. Outbreaks and hospitalizations also decreased rapidly. From 1995 to 1998, hospitalization rates ranged from 2.2 to 3.3 per 100,000 population but by 2006-2010 this had declined to 0.2 per 100,000 in Antelope Valley and 0.5 per 100,000 in Philadelphia. Chickenpox is an example that can also help to answer the question of whether better hygiene or vaccination are in fact responsible for the reduced rates of disease. Although both are important, a more recently adopted vaccination such as chickenpox can demonstrate the effects of vaccination in reducing the rate of disease after the importance of hygiene was discovered and became a preventative measure against disease. As hygiene standards already reached high levels, the additional benefit of the vaccine is confirmed. The impact on disease rates demonstrate it is not hygiene but vaccination that reduced the incidence of chickenpox so dramatically in the US. <Image filename="Chickenpox-cases-in-US.png" alt=""/> ## Which countries have mandatory childhood vaccination policies? With the widespread rollout of [COVID-19 vaccines](http://ourworldindata.org/covid-vaccinations) globally, some countries have started to consider mandatory vaccination, although no country has yet to make vaccines mandatory for its population.{ref}Gostin, L. O., Salmon, D. A. and Larson, H. J. (2021) ‘Mandating COVID-19 Vaccines’, _JAMA_. American Medical Association, 325(6), p. 532. doi: 10.1001/jama.2020.26553.{/ref} While COVID-19 has resurfaced the debate on vaccination policies, it has been an important topic for many other diseases. The World Health Organization (WHO) estimates that vaccines save two to three million lives each year (excluding COVID). The development of vaccines against vaccine-preventable childhood diseases has been a key driver in the decline of [child mortality](http://ourworldindata.org/child-mortality). Despite it being such an important topic, it is surprising that information about which countries have mandatory vaccine policy is lacking, and it is childhood vaccines under a country’s national immunization schedules that are most commonly made mandatory. In this article we present a new global dataset which looks at childhood vaccination policies across the world. ## How do childhood vaccination policies vary across the world? We recently charted mandatory childhood vaccine policies worldwide as they are becoming an increasingly important policy intervention for governments trying to address low vaccination rates.{ref}Vanderslott, S., & Marks, T. (2021). [Charting mandatory vaccination policies worldwide](https://www.sciencedirect.com/science/article/pii/S0264410X21005478). _Vaccine_.{/ref} The term ‘mandatory’ and ‘mandates’ are taken to mean quite different things across countries. Whilst the term is commonly used it is poorly defined.{ref}Attwell, K. and C. Navin, M. (2019) ‘Childhood Vaccination Mandates: Scope, Sanctions, Severity, Selectivity, and Salience’, _The Milbank Quarterly_, 97(4), pp. 978–1014. doi: 10.1111/1468-0009.12417.{/ref} Mandates require vaccination for a certain purpose, most commonly related to school entry for children. While definitional disagreements still persist, it remains important to better understand what policies are in place across countries and the reasons driving changes in policy over time. Our list indicates whether a country has a mandatory vaccination policy for one or more vaccine and the strictness of the mandate on a scale ranging across three levels: mandatory, mandatory for school entry, or recommended. The childhood vaccines include the vaccines that protect from [measles,](https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide) mumps, rubella, [diphtheria, tetanus, pertussis](https://ourworldindata.org/grapher/immunization-coverage-against-diphtheria-tetanus-and-pertussis-dtp3-vs-gdp-per-capita), [polio](https://ourworldindata.org/grapher/polio-rate-of-cases-vs-vaccination-coverage), rabies, hepatitis B, [rotavirus](https://ourworldindata.org/rotavirus-vaccine), [haemophilus influenzae type B](https://ourworldindata.org/grapher/hib-vaccine), and [tuberculosis](https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds?country=~OWID_WRL) – some of which are administered as combined vaccines. We have classified a country as having a mandatory policy if they mandate for at least one vaccine. The differences in vaccination policy across the world are shown in the map. By covering 149 countries we could identify some trends around where and why vaccines are mandatory today. <Chart url="https://ourworldindata.org/grapher/mandatory-childhood-vaccination"/> ### _Note: this is a live dataset that relies on crowdsourcing to note policy changes. If you are aware of any new policies or policy changes for any country please do get in touch at: [email protected]._ ## How do mandatory vaccination policies vary by region? We found that assessing policies across WHO regions – European, Americas, Western Pacific, African, and Eastern Mediterranean – was a useful way to break down our analysis of policies worldwide. In the chart you see a breakdown of the number of countries with a given policy mandate. You can view this by region by using the "Change region" toggle on the interactive chart. Europe has a mixture of mandatory and recommended policies. But most European countries – 16 out of 28 – do not have mandatory vaccination. European countries were among the first to introduce mandatory vaccination for smallpox in the early 19th century, which also led to early push-back. The early introduction and early push-back, along with present-day approaches to foster mutual trust and responsibility between citizens and the health authorities, may be part of the reason why vaccination is often recommended rather than mandated in many European countries.{ref}Stuart Blume (2017) _Immunization: How Vaccines became Controversial - Stuart Blume - Google Books_. Reaktion Books.{/ref} Countries of the former-USSR (Union of Soviet Socialist Republics) or under the influence of the Eastern Bloc previously had mandatory vaccination, and many kept this policy in the post-USSR era. Most countries in the Americas – 29 out of 35 – have mandatory vaccinations. In the USA, vaccination is regulated by individual states though it is mandatory for school entry in all of them. In Canada, only three provinces have legislated mandatory vaccination policies that apply to children enrolling in school. In the Western Pacific region, changes to mandatory policies have gone in both directions. Some countries such as Singapore have moved towards mandatory vaccinations whilst others, such as South Korea transitioned away from mandatory to recommended vaccines in 1999. For other countries, mandatory policies are more ambiguous. In China, there is no evidence of specific legislation mandating vaccines, despite many references to such claims in the literature.{ref}Attwell, K., Drislane, S. and Leask, J. (2019) ‘Mandatory vaccination and no fault vaccine injury compensation schemes: An identification of country-level policies’, _Vaccine_. Elsevier Ltd, 37(21), pp. 2843–2848. doi: 10.1016/j.vaccine.2019.03.065.{/ref} It was difficult to obtain information about vaccination policies across African countries, suggesting the absence of specific policies in the region. However, the policies we did find were for mandatory vaccination. Most countries in the Eastern Mediterranean region have mandatory vaccines. Israel is an exception in only recommending vaccination, based on a vaccination schedule outlined by the National Immunization Technical Advisory Group. There are a number of countries in South-East Asia with mandatory vaccination. India is similar to other large countries, with varying policies on mandatory vaccination at the state level. Finally, we note that there are some countries that have mandatory policies at a sub-country level such as in Canadian provinces and Indian and Australian states but we have classified these countries as to the national policy and the policies cover most of the country. <Chart url="https://ourworldindata.org/grapher/number-countries-mandatory-vaccination?country=~OWID_WRL"/> ## What drives the introduction of mandatory vaccinations? Overall, we found that the occurrence of recent outbreaks is a major factor in the introduction of mandatory vaccination, particularly for high and upper-middle-income countries in Europe. Germany, for example, made measles vaccination mandatory for school and day-care attendance in 2020 following large outbreaks.{ref}Rezza, G. (2019) ‘Mandatory vaccination for infants and children: the Italian experience’, _Pathogens and Global Health_. Taylor and Francis Ltd., pp. 291–296. doi: 10.1080/20477724.2019.1705021.{/ref} Similarly, Serbia tightened mandatory vaccination laws following a measles outbreak in 2014 to 2015 by introducing harsher penalties.{ref}Pejin LS. Tightening measures for compliance with vaccination in Serbia ESPN Flash Report. European Commission; 2016.{/ref} Trends of reported cases of measles can be explored in detail [here](https://ourworldindata.org/grapher/reported-cases-of-measles?country=~DEU). Secondly, many low- and lower-middle-income countries have resorted to mandatory vaccination policies because of a lack of other policy options. Nonetheless, many have still missed their target vaccination rates due to problems with vaccine supply, delivery, and access. In Guyana for example, vaccination is mandatory, yet vaccination coverage is hindered by the management of the supply chain in keeping storage temperatures consistent and the distribution of freeze-sensitive vaccines.{ref}UNICEF. Guyana Situation Analysis of Children and Women; 2016. Available at: [https://www.unicef.org/sitan/](https://www.unicef.org/sitan/) [accessed: 10 April 2020].{/ref} In Nigeria, vaccination is mandatory, and several states have enacted legislation criminalising vaccine refusal. Yet as Onyemelukwe (2016) argues, there are structural, logistical, political, systemic, religious and cultural obstacles to the effective distribution and uptake of vaccines, ranging from cold chain issues, to corruption and security issues.{ref}Onyemelukwe, C. (2016) ‘Can legislation mandating vaccination solve the challenges of routine childhood immunisation in Nigeria?’, _Oxford University Commonwealth Law Journal_. Taylor and Francis Ltd., 16(1), pp. 100–124. doi: 10.1080/14729342.2016.1244450.{/ref} There is thus often variation between vaccination in policy compared to in practice. These findings will be useful to inform policymakers considering the merits of mandatory vaccination: 1) In the past, an outbreak of a disease (such as measles) has led to introduction of mandatory vaccines even in countries where previously all vaccinations were recommended; 2) Making a vaccine mandatory should not be the only policy tool but needs to be combined with strong access and availability of vaccines; 3) It is not just a matter of whether to mandate a vaccine, but how this mandate will be enforced, whether people will comply, and the impact on state-citizen relations. In summary, mandatory vaccination must be considered with caution. A country’s past experience with mandates, vaccination services, ability for enforcement, public attitudes, and the current state of disease outbreaks will all play a part in whether mandatory vaccination should be introduced. --- # Coverage, Impact, and Potential --- ## Diseases preventable through vaccination The chart shows the number of global deaths caused by some of the most common and serious vaccine-preventable diseases. By selecting ‘change country’ it is possible to see this change for any country in the world and extending the timeline will let you see the change in deaths over time. There are more diseases for which vaccines are available now and even more are under development currently. The WHO publishes list of [26 diseases](http://www.who.int/immunization/diseases/en/) for which vaccines are available – including Japanese encephalitis, pneumococcal disease, varicella/chicken pox, HPV, Hepatitis A and rotavirus. <Chart url="https://ourworldindata.org/grapher/Deaths-caused-by-vaccine-preventable-diseases-over-time"/> ## Diphtheria, Tetanus, and Pertussis vaccine Diphtheria, tetanus, and pertussis are all bacterial diseases and a combination vaccine against all three diseases is commonly used. * Diphtheria primarily infects the throat and upper airways and is fatal in 5 – 10% of cases. * Tetanus is not passed person-to-person but through spores of a bacteria living in soil and animal intestinal tracts. These bacteria enter the body through wounds and release a toxin that affects the nerves, which causes muscle stiffness and spasms. * Pertussis is a highly contagious disease of the respiratory tract, commonly known as whooping cough. Children who contract pertussis tend to have coughing spells that last four to eight weeks, but the highest fatality is in young infants. Vaccinating health workers and pregnant women is the most effective strategy for preventing disease in infants too young to be vaccinated. The chart shows the progress over time of DTP3 immunization coverage of children around the world. By clicking on any country you can see the change in that country over time. The WHO [reports](https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=OWID_WRL) in 2017 that 85% of infants worldwide (116.5 million infants) received 3 doses of diphtheria-tetanus-pertussis vaccine (DTP3). Also in 2016 130 countries had reached at least 90% coverage with the DTP3 vaccine.{ref}See the WHO here: [http://www.who.int/mediacentre/factsheets/fs378/en/](http://www.who.int/mediacentre/factsheets/fs378/en/){/ref} If we look at [the change over time by world region](https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=East%20Asia%20%26%20Pacific+Europe%20%26%20Central%20Asia+Latin%20America%20%26%20Caribbean+Middle%20East%20%26%20North%20Africa+North%20America+South%20Asia+Sub-Saharan%20Africa) it is South Asia in particular that stands out. While 85% of one-year-olds today are immunized, that same figure was as low 6% in 1980. Within each country there can be substantial differences in vaccination coverage. The [WHO reports](http://www.who.int/gho/urban_health/services/dpt3_vaccination/en/) that in all regions children in the richest 20% of urban households are more likely to get immunized than children from the poorest 20% of households. Some countries lag behind however. Ukraine stands out as having particularly low DTP vaccination rates in 2015 of 23%, falling from 98% in 1999. Ed Holt writing for the Lancet in 2013 attributed the decline to: "A combination of public mistrust in vaccinations, poor vaccine supply, and corruption in the health system".{ref}Holt, Ed., Ukraine at risk of polio outbreak, The Lancet , Volume 381 , Issue 9885 , 2244 [here](https://www.ncbi.nlm.nih.gov/pubmed/23819156){/ref} Therefore Ukraine is suffering from a combination of factors effecting vaccination rates from public attitudes and systemic delivery problems. Furthermore, the unrest since 2014 and Russian military intervention is likely to have worsened matters. Today only Equatorial Guinea reports even lower rates at 16%. As [Human Rights Watch observes](https://www.hrw.org/world-report/2015/country-chapters/equatorial-guinea), very little of the country's wealth is being directed towards the needs of citizens. The number of under-vaccinated children in Nigeria remains high, with [3.4 million children going without the DTP3 vaccine (compared with 2.9 million in India](http://www.gavi.org/library/news/statements/2017/vaccine-progress-in-developing-countries-in-danger-of-stalling/)). <Chart url="https://ourworldindata.org/grapher/share-of-children-immunized-dtp3"/> ## Measles vaccine Measles is a highly contagious virus-caused disease that, despite a safe and effective vaccine being available, infects thousands of people globally. Around 90,000 people die because of measles every year, the huge majority of whom (87%) are children younger than 5. Measles vaccination has resulted in an 84% drop in measles deaths between 2000-2016.{ref}Figures are updated by the WHO here: http://www.who.int/news-room/fact-sheets/detail/measles{/ref} The world map shows the share of children vaccinated with the first dose of measles vaccine. You can switch to the 'chart' view to see the global coverage against vaccines. The measles vaccine was developed in 1963. In 1983 – the first year for which global data is available – only every second child was vaccinated against measles. In the latest data this share has increased to 85% globally up from 72% in 2000.{ref}See the WHO here: [http://www.who.int/mediacentre/factsheets/fs286/en/](http://www.who.int/mediacentre/factsheets/fs286/en/){/ref} The sub-Saharan African region achieves the lowest measles vaccination rates, along with conflict-ridden and unstable countries (e.g. Syria, Afghanistan, and Iraq). But also some of the Pacific Islands – such as Papua New Guinea and Vanuatu – are performing poorly. Today (data from 2014) 114.3 million children are vaccinated against measles every year, which is on average 313,071 children every single day.{ref}In 2014 there were [135.2 million one-year olds](https://ourworldindata.org/grapher/number-of-one-year-olds). Of these [84.52% received the vaccine against measles](https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles?tab=chart). This means that 135.2 *0.8452 = 114.27 million children were vaccinated.{/ref} <Chart url="https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles"/> ### Second dose of measles vaccine provides greater protection As of 2018, the WHO estimate that 171 countries had included a second dose as part of routine immunization. Two doses are needed for a higher level of protection.{ref}Gaston De Serres, Jill Sciberras, Monika Naus, Nicole Boulianne, Bernard Duval, and Louis Rochette (1999) – Protection after Two Doses of Measles Vaccine Is Independent of Interval between Doses. In The Journal of Infectious Diseases, Volume 180, Issue 1, 1 July 1999, Pages 187–190, [https://doi.org/10.1086/314847](https://doi.org/10.1086/314847) Online here: [https://academic.oup.com/jid/article/180/1/187/990623](https://academic.oup.com/jid/article/180/1/187/990623).{/ref} The map here shows the coverage of the second dose (MCV2) of the measles vaccine. The current global average is 67%. The coverage is lowest in South Africa and many countries in Sub-Saharan Africa still have not introduced the vaccine into their immunization coverage.{ref}For guidelines on recommendations for the second dose of measles vaccine see here [https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf](https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf){/ref} [This scatterplot](https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles-vs-share-vaccinated-against-dpt3) compares the vaccination coverage against measles with the coverage against DTP3. <Chart url="https://ourworldindata.org/grapher/share-of-children-vaccinated-with-mcv2"/> ### Global decline of measles The second visualization shows the discussed increase of the global vaccination coverage of one-year-olds and the simultaneous decline of reported cases of the disease; from close to 1,000 cases per million people globally to 28 cases per million. This represents a 33-fold reduction. For country by country change over time see [this visualization](https://ourworldindata.org/grapher/reported-cases-of-measles). <Chart url="https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide"/> ## Rotavirus vaccines The first widely-used rotavirus vaccine was approved in the United States in 2006. Today, there are four oral rotavirus vaccines recommended for use by the World Health Organisation (WHO): Rotarix, RotaTeq, RotaSiil, and Rotavac.{ref}World Health Organization. (2019). _Rotavirus_. [online] Available at: [https://www.who.int/immunization/diseases/rotavirus/en/](https://www.who.int/immunization/diseases/rotavirus/en/) [Accessed 14 Aug. 2019].{/ref} Rotarix and RotaTeq are the most widely used and both have shown good efficacy against rotavirus infections in clinical trials.{ref}Ruiz-Palacios, G. M., Pérez-Schael, I., Velázquez, F. R., Abate, H., Breuer, T., Clemens, S. C., … & Cervantes, Y. (2006). [Safety and efficacy of an attenuated vaccine against severe rotavirus gastroenteritis](https://www.nejm.org/doi/full/10.1056/nejmoa052434). _New England Journal of Medicine_, _354_(1), 11-22.{/ref}{ref}Vesikari, T., Matson, D. O., Dennehy, P., Van Damme, P., Santosham, M., Rodriguez, Z., … & Shinefield, H. R. (2006). [Safety and efficacy of a pentavalent human–bovine (WC3) reassortant rotavirus vaccine](https://www.nejm.org/doi/full/10.1056/nejmoa052664). _New England Journal of Medicine_, _354_(1), 23-33.{/ref} Since the use of rotavirus vaccines have been approved, they have had a notable impact on the reduction of rotavirus-related deaths. According to a study published in 2018, the use of rotavirus vaccines prevented approximately 28,900 child deaths globally in 2016. However, as the chart shows, full vaccine use – that is a 100% coverage globally – could have prevented an additional 83,200 deaths.{ref}Troeger, C., Khalil, I. A., Rao, P. C., Cao, S., Blacker, B. F., Ahmed, T., … & Kang, G. (2018). [Rotavirus vaccination and the global burden of rotavirus diarrhea among children younger than 5 years](https://jamanetwork.com/journals/jamapediatrics/fullarticle/2696431). _JAMA Pediatrics_, _172_(10), 958-965.{/ref} This means that, even at the current rates of efficacy, 53% of all deaths in children under-5 from rotavirus in 2016 could have been avoided by full vaccine coverage. In addition to saving lives, the rotavirus vaccine also reduces the burden on healthcare systems. Between 2008 and 2016 the introduction of the rotavirus vaccine has reduced the number of diarrhea-related hospital admissions on average by 40%.{ref}Aliabadi, Negar, et al. ["Global impact of rotavirus vaccine introduction on rotavirus hospitalisations among children under 5 years of age, 2008–16: findings from the Global Rotavirus Surveillance Network."](https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(19)30207-4/fulltext)_The Lancet Global Health_7.7 (2019): e893-e903.{/ref} <Chart url="https://ourworldindata.org/grapher/avertable-deaths-from-rotavirus-with-full-vaccine-coverage"/> ### Rotavirus vaccine could save the lives of even more children If there is so much scope for saving more children’s lives, what is the reason that these children are still dying? There are two key barriers to achieving the full potential of the rotavirus vaccine: immunization rates, and the efficacy of the vaccine in specific regions. ### Immunisation rates are still too low According to the WHO, by the end of 2018, 101 countries were using the rotavirus vaccine. The major drivers for the introduction of the vaccine are the burden of diarrheal diseases, the availability of funding, and a favourable political climate for vaccines.{ref} The cost of rotavirus vaccines varies by country. For example, countries with a gross national income per capita of less than US$1,000 receive subsidies from the Global Alliance for Vaccines and Immunisation, and there the cost per dose is [set between US$2.10 - 3.20](https://www.unicef.org/supply/files/Rotavaccine.pdf). With additional co-financing options can reduce the costs [down to US$0.13](https://www.sabin.org/sites/sabin.org/files/frederic_debellut.pdf). In high-income countries, such as the US, the cost per dose is between [US$70 and 95](https://www.cdc.gov/vaccines/programs/vfc/awardees/vaccine-management/price-list/index.html) Countries are more likely to introduce the vaccine if the political environment is favourably disposed towards them. For example, if a country has set a high priority on achieving the Millennium Development Goal targets or the introduction of vaccines is seen as a positive news story, especially during election years. Burchett, H. E. D., Mounier-Jack, S., Griffiths, U. K., Biellik, R., Ongolo-Zogo, P., Chavez, E., … & Molla, M. (2012). [New vaccine adoption: qualitative study of national decision-making processes in seven low-and middle-income countries](https://academic.oup.com/heapol/article/27/suppl_2/ii5/594662). _Health policy and planning_, _27_(suppl_2), ii5-ii16.{/ref} The vaccine is only given to children – it’s recommended that the vaccination should be initiated 15 weeks after birth and finished by the 32nd week. However, the global coverage is still very low: it is estimated that just 35% of under one-year-olds were vaccinated in 2018.{ref}World Health Organization (2019). _Immunization coverage_. [online] Available at: [https://www.who.int/news-room/fact-sheets/detail/immunization-coverage](https://www.who.int/news-room/fact-sheets/detail/immunization-coverage) [Accessed 14 Aug. 2019].{/ref} The map shows the WHO estimates on the share of one-year olds who received the full recommended dosage of the vaccine (two immunizations for Rotarix vaccine or three immunizations for RotaTeq vaccine). For many countries where data coverage is low, it’s expected that the share of infants receiving the vaccine is very low. Some countries however did see rapid increases in rates of immunization. In a period of only a few years countries including [Sudan, Malawi and Gambia](https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine?tab=chart&time=2011..2018&country=SDN+GMB+MWI) have increased immunisation rates from below 10% to 80-95% – click on the country to see the change over time. <Chart url="https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine"/> ### Vaccine efficacy differs by region Since most [rotavirus cases](https://ourworldindata.org/grapher/child-deaths-from-rotavirus) occur in Sub-Saharan Africa where [mortality from rotavirus infection is also the highest](https://ourworldindata.org/grapher/child-mortality-rate-from-rotavirus?tab=chart), it is essential to increase and maintain high immunisation coverage in this region. However, in addition to delivering the vaccine for those who need it, we also need to work on improving its efficacy. Vaccine efficacy for the rotavirus vaccine is defined as the percentage reduction of the rate of diarrhea incidences in vaccinated versus unvaccinated groups of children. It is well established that the efficacy of the rotavirus vaccine is not the same across all countries — in countries with high child mortality rates the vaccine shows much lower efficacy.{ref}Clark, Andrew, et al. ["Efficacy of live oral rotavirus vaccines by duration of follow-up: a meta-regression of randomised controlled trials."](https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext)_The Lancet Infectious Diseases_ (2019).{/ref} The chart is from a recent study by Clark et _al._, which looked at how the efficacy of live oral rotavirus vaccines changes in different countries following vaccination. The chart shows that in countries with high child mortality rates, not only is the immediate vaccine efficacy lower – 98% in low child mortality countries versus 66% in high child mortality countries – but also the vaccine efficacy decreases faster in high child mortality countries over time.{ref}The [Clark et al.](https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext) (2019) study defined low child mortality rate as less than 1.3% of newborns; medium mortality rate as between 1.35% and 2.81%; and high mortality rate as more than 2.81%{/ref} Five years after vaccination, the rotavirus vaccine reduces the chances of getting diarrhea by 90% in low child mortality countries and only by 30% in high mortality countries. <Image filename="Rotavirus-vaccine-efficacy-by-child-mortality-group-1.png" alt=""/> The table shows how good the rotavirus vaccine is at preventing severe diarrhea and reducing hospitalization due to diarrhea in children under-5 in different regions.{ref}Lamberti, L. M., Ashraf, S., Walker, C. L. F., & Black, R. E. (2016). [A systematic review of the effect of rotavirus vaccination on diarrhea outcomes among children younger than 5 years](https://www.ingentaconnect.com/content/wk/inf/2016/00000035/00000009/art00016). _The Pediatric Infectious Disease Journal_, _35_(9), 992-998.{/ref} In high-income countries, rotavirus vaccination has been shown to reduce the cases of severe rotavirus diarrhea by 91% and hospitalization by 94%. In Eastern Asia and Latin America, the effectiveness rates are lower but still high – preventing 88% and 80% of severe diarrhea cases, respectively. However, effectiveness in South Asia and Sub-Saharan Africa is significantly lower, only reducing severe diarrhea in around half of the cases. <div class="raw-html-table__container"><table><thead><tr><th scope="col" colspan="1">Outcome </th><th scope="col" colspan="1">Region</th><th scope="col" colspan="1">Vaccine effectivness</th></tr></thead><tbody><tr><td colspan="1" rowspan="5">Severe rotavirus diarrhea</td><td colspan="1" rowspan="1">Developed</td><td colspan="1" rowspan="1">91%</td></tr><tr><td colspan="1" rowspan="1">Eastern Asia and Southeast Asia</td><td colspan="1" rowspan="1">88%</td></tr><tr><td colspan="1" rowspan="1">Latin America and Caribbean</td><td colspan="1" rowspan="1">80%</td></tr><tr><td colspan="1" rowspan="1">Southern Asia</td><td colspan="1" rowspan="1">50%</td></tr><tr><td colspan="1" rowspan="1">Sub-Saharan Africa</td><td colspan="1" rowspan="1">46%</td></tr><tr><td colspan="1" rowspan="4">Hospitalization due to rotavirus infection</td><td colspan="1" rowspan="1">Developed</td><td colspan="1" rowspan="1">94%</td></tr><tr><td colspan="1" rowspan="1">Eastern Asia and Southeast Asia</td><td colspan="1" rowspan="1">94%</td></tr><tr><td colspan="1" rowspan="1">Latin America and Caribbean</td><td colspan="1" rowspan="1">84%</td></tr><tr><td colspan="1" rowspan="1">Sub-Saharan Africa</td><td colspan="1" rowspan="1">58%</td></tr></tbody></table></div> The reasons for different responses to the vaccine are not entirely clear.{ref}Patel, M., Shane, A. L., Parashar, U. D., Jiang, B., Gentsch, J. R., & Glass, R. I. (2009). [Oral rotavirus vaccines: how well will they work where they are needed most?](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3673012/#R3). _The Journal of Infectious Diseases_, _200_, S39-S48.{/ref} {ref}Parker, E. P., Ramani, S., Lopman, B. A., Church, J. A., Iturriza-Gomara, M., Prendergast, A. J., & Grassly, N. C. (2018). [Causes of impaired oral vaccine efficacy in developing countries](https://www.futuremedicine.com/doi/10.2217/fmb-2017-0128?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dwww.ncbi.nlm.nih.gov&). _Future microbiology_, _13_(1), 97-118.{/ref} It is likely that the gut responses to the oral rotavirus vaccines in children in lower-income countries are different. This may be due to a variety of causes, including [micronutrient deficiencies](https://ourworldindata.org/micronutrient-deficiency), pre-vaccination exposure to certain pathogens, and the presence of chronic conditions such as [malaria](https://ourworldindata.org/malaria) or [HIV](https://ourworldindata.org/hiv-aids). Overall, the poor gut response to the live vaccine means the efficacy of the vaccine is reduced. Taking all of the above mentioned points into account, there are several interventions that could increase the benefits of the rotavirus vaccine even further. In addition to increasing the vaccine coverage, improving nutritional health (of both infants and mothers) and improving hygiene and sanitation conditions (to lower the prevalence of damaging pathogens) could have positive effects on the vaccine’s efficacy. We are still at quite an early stage of the rotavirus vaccine use. Although the vaccine has brought huge benefits already, it could go even further. Improving vaccination coverage, particularly across Sub-Saharan Africa and South Asia is key to continued reduction of childhood deaths from diarrhea. Even at moderate levels of vaccine efficacy, a significant number of additional additional child deaths could be prevented every year. The bar chart above that shows the number of preventable deaths illustrates the potential for extended vaccine coverage to save many more lives. And this is already taking into account the regional differences in the vaccine’s effectiveness. In addition to increased coverage, improving the effectiveness of the vaccine would go even further in tackling one of the leading causes of death. ## Pneumococcal vaccines There are a number of ways we could reduce the number of children dying from pneumonia, including eliminating the major risk factors such as [undernutrition](https://ourworldindata.org/hunger-and-undernourishment) and [air pollution](https://ourworldindata.org/indoor-air-pollution), and providing better [access to treatment](https://ourworldindata.org/grapher/pneumonia-careseeking). But we have another highly effective intervention: a [vaccine](https://ourworldindata.org/vaccination) against the major pathogen responsible for pneumonia in children. _Streptococcus pneumoniae _is the leading cause of pneumonia in children under 5 — it was responsible for 52% of all fatal pneumonia cases in children in 2016.{ref}Troeger, C., Blacker, B., Khalil, I. A., Rao, P. C., Cao, J., Zimsen, S. R., ... & Adetifa, I. M. O. (2018). [Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory infections in 195 countries, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016.](https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(18)30310-4/fulltext)_ The Lancet Infectious Diseases_, _18_(11), 1191-1210.{/ref} Pneumococcal vaccines are vaccines that target _S. pneumoniae_ bacteria. Here we look at their effectiveness and how we can maximise the number of children they save. ### The coverage of pneumococcal vaccines is still low Since the World Health Organisation (WHO) started recommending including pneumococcal vaccines in national immunisation programmes for children in 2007, there has been a progressive increase in the number of countries using the vaccine. You can see the uptake in the vaccine across the world using the ‘play’ button on the map below. But the coverage of pneumococcal vaccines is still low in many countries. In India and Nigeria – the two countries with the [greatest number](https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5) of childhood deaths from pneumonia in 2019 – only 44% and 58% of one-year-olds are vaccinated, respectively. In 2018, less than half (47%) of one-year-olds in the world received the full course of pneumococcal vaccination. This means that 55 million children who could be protected by the vaccine are still not vaccinated against it — an appallingly high number for a vaccine that not only protects from pneumonia, the leading cause of childhood death, but also a range of other diseases (as discussed below).{ref}Who.int. (2019) – [_Immunization coverage_](https://www.who.int/news-room/fact-sheets/detail/immunization-coverage). [online] [Accessed 10 Sep. 2019]. [http://view-hub.org/viz/](http://view-hub.org/viz/) (Go to PCV —> PCV - Vaccine Access —> Children without Access){/ref} <Chart url="https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine"/> ### How do pneumococcal vaccines work? _Streptococcus pneumonia_, often simply referred to as pneumococcus, is a bacterium that is often found in the upper respiratory tract of healthy people. Generally, the bacterium is harmless or causes milder illnesses such as bronchitis, sinusitis, and ear infections. Pneumococcal vaccines are effective against these milder illnesses as well, but importantly also protects from what is called pneumococcal invasive disease (PID). PID occurs when the pneumococcus moves from colonizing the upper respiratory tract to colonizing sites that are normally sterile, such as blood, cerebrospinal fluid or pleural cavity (fluid-filled space surrounding the lungs).{ref}Hanada, S., Pirzadeh, M., Carver, K. Y., & Deng, J. C. (2018). [Respiratory Viral Infection-Induced Microbiome Alterations and Secondary Bacterial Pneumonia.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6250824/)_Frontiers in immunology_, _9_, 2640.{/ref} Bacterial invasion leads to life-threatening diseases such as sepsis, meningitis and severe pneumonia. <Chart url="https://ourworldindata.org/grapher/child-deaths-from-streptococcus-by-disease"/> There are two types of pneumococcal vaccines available: conjugated polysaccharide pneumococcal vaccine (PCV) and non-conjugated polysaccharide pneumococcal vaccine (PPSV). Both vaccines are designed to elicit immune responses against multiple serotypes of pneumococcus, which are defined by the different immune responses to the sugars found on the bacterial surface.{ref}Song, J. Y., Nahm, M. H., & Moseley, M. A. (2013). [Clinical implications of pneumococcal serotypes: invasive disease potential, clinical presentations, and antibiotic resistance](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3546102/). _Journal of Korean medical science_, _28_(1), 4-15.{/ref} To be broadly effective, the vaccines need to protect against a certain number of these pneumococcal serotypes, but it is not necessary to include all possible serotypes because only a limited subset is responsible for 70%-80% of invasive pneumococcal disease.{ref}The number of serotypes included in the vaccine is generally indicated in its name, e.g. PCV13 is pneumococcal conjugate vaccine effective against 13 bacterial serotypes. Vaccines including progressively more serotypes have been introduced over the years, PCV7 was introduced in 2000 and today the most commonly used PCV13 was introduced in 2010. Hausdorff, W. P., Feikin, D. R., & Klugman, K. P. (2005). [Epidemiological differences among pneumococcal serotypes.](https://www.ncbi.nlm.nih.gov/pubmed/15680778/)_The Lancet infectious diseases_, _5_(2), 83-93.{/ref} However, as we’ll discuss later, this variety of different pneumococcal serotypes is important to keep in mind because as vaccine coverage increases we may see a replacement of the vaccine-included serotypes with the less dominant ones, which will mean new vaccine versions will be required. While there are two types of pneumococcal vaccines available, for children under two years old only the conjugated (i.e. PCV) vaccines are recommended because the non-conjugated versions (i.e. PPSV) are not effective at such a young age.{ref}The current non-conjugate vaccine, PPSV23, is generally only given to adults or as a single dose following two immunisations with PCV13 in children older than 2. Golos, M., Eliakim‐Raz, N., Stern, A., Leibovici, L., & Paul, M. (2016). [Conjugated pneumococcal vaccine versus polysaccharide pneumococcal vaccine for prevention of pneumonia and invasive pneumococcal disease in immunocompetent and immunocompromised adults and children.](https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD012306/full)_Cochrane Database of Systematic Reviews_, (8).{/ref} ### How effective are pneumococcal vaccines? In clinical trials PCV has shown 80% efficacy in reducing invasive pneumococcal disease caused by the bacterial serotypes included in the vaccine formulation. Vaccinated children are 27% less likely to be diagnosed with pneumonia and 11% less likely to die from it.{ref}The 27% refers to X-ray-defined cases of pneumonia. For clinically defined pneumonia, a less accurate diagnosis than X-ray-defined cases, the number is 6%. Both of these indicators refer to cases of pneumonia caused by any pathogen not only pneumococcus. Lucero, M. G., Dulalia, V. E., Nillos, L. T., Williams, G., Parreño, R. A. N., Nohynek, H., ... & Makela, H. (2009). [Pneumococcal conjugate vaccines for preventing vaccine‐type invasive pneumococcal disease and X‐ray defined pneumonia in children less than two years of age](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6464899/). _Cochrane Database of Systematic Reviews_, (4).{/ref} Several studies have attempted to estimate how many lives PCV vaccination has saved and could possibly save. One _Lancet _study concluded that between 2000 and 2015, in 120 countries the number of childhood deaths caused by pneumococcus fell from 600,000 to 294,000 — a decline of 54%. Most of this decline was attributed to the PCV vaccines: over this period, it’s estimated these vaccines saved the lives of 250,000 children. The majority of these deaths would have been caused by pneumonia, but the vaccine also prevented deaths from pneumococcal meningitis and other diseases.{ref}Wahl, B., O'Brien, K. L., Greenbaum, A., Majumder, A., Liu, L., Chu, Y., ... & Rudan, I. (2018). [Burden of Streptococcus pneumoniae and Haemophilus influenzae type b disease in children in the era of conjugate vaccines: global, regional, and national estimates for 2000–15.](https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30247-X/fulltext)_ The Lancet Global Health_, _6_(7), e744-e757.{/ref} ### How many child deaths could be averted by pneumococcal vaccines? The chart shows how estimates of the potential impact of the pneumococcal vaccine. It is based on a recent study published in _The Lancet Global Health_ journal, which calculated that if the PCV vaccine coverage would reach at least the levels of the [vaccination against diphtheria, tetanus and pertussis](https://ourworldindata.org/grapher/share-of-children-immunized-dtp3) (DTP3), the lives of 399,000 children under 5 could be saved.{ref}Chen, C., Liceras, F. C., Flasche, S., Sidharta, S., Yoong, J., Sundaram, N., & Jit, M. (2019). [Effect and cost-effectiveness of pneumococcal conjugate vaccination: a global modelling analysis.](https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30422-4/fulltext)_ The Lancet Global Health_, _7_(1), e58-e67.{/ref} Additionally the researchers estimate that 54.6 million pneumonia episodes annually could be averted. These number estimate the impact of the PCV vaccination relative to a world without that vaccine – since the vaccine is already used it means that some of these lives are already being saved by the PVC vaccination. However, in many countries [PCV vaccination rates still fall far below the DTP3 rates](https://ourworldindata.org/grapher/diphtheria-tetanus-pertussis-vaccine-vs-pneumococcal-vaccine-coverage), making clear that we still haven’t used the pneumococcal vaccine to its full potential. <Chart url="https://ourworldindata.org/grapher/pneumococcal-vaccination-averted-deaths"/> ### What can we do to improve the coverage and effectiveness of pneumococcal vaccines? A continued increase in immunization coverage and the introduction of PCV vaccines into countries which don’t yet use them is important if we want to make use of the full potential of pneumococcal vaccines. PCV vaccines are amongst the most expensive vaccines in national immunisation programmes. The price ranges from $3.05 per dose in GAVI{ref} GAVI (Global Alliance for Vaccines and Immunisation) is a non-profit organisation that provides access to vaccination programs for low-income countries by providing financial support and individual expertise.{/ref} supported low-income countries to $169 in high-income countries such as the United States.{ref}O'Brien, K. L. (2018). [When less is more: how many doses of PCV are enough?.](https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc)_ The Lancet Infectious Diseases_, _18_(2), 127-128.{/ref} For low-middle-income countries who are transitioning from GAVI support the increasing future costs of vaccination place a considerable strain on national healthcare budgets.{ref}For example Kenya has recently entered a transition phase during which it will pay a larger and larger portion of the PCV vaccine cost. By 2027 Kenya will have to pay the full $9 price for a three-dose course child vaccination. The 2016 [per capita healthcare expenditure in Kenya](https://databank.worldbank.org/Kenya-healthcare-per-capita-/id/58f0a890) was around $66 (5% of the GDP), clearly $9 per child is not a trivial cost. Simonsen, L., van Wijhe, M., & Taylor, R. (2019). [Are expensive vaccines the best investment in low-income and middle-income countries?](https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext). _The Lancet Global Health_, _7_(5), e548-e549. Ojal, J., Griffiths, U., Hammitt, L. L., Adetifa, I., Akech, D., Tabu, C., ... & Flasche, S. (2019). [Sustaining pneumococcal vaccination after transitioning from Gavi support: a modelling and cost-effectiveness study in Kenya.](https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext)_ The Lancet Global Health_, _7_(5), e644-e654.{/ref} But given the high burden of pneumococcal diseases, even at high prices, PCV vaccines are considered to be cost-effective, with an estimated return of investment in low- and middle-income countries of around 3.{ref}The return of investment was estimated for a projected coverage for individual countries for the decade between 2011 and 2020. It means that the economic benefits (as measured by the costs of vaccination program subtracted from the reduced costs of treatment and productivity loss) of using the vaccine are 3 times higher than no vaccine use. To reduce costs, some countries may also consider switching to a two rather than three dose immunization schedule, but more research on the effectiveness of this schedule in different countries is needed. See O'Brien et al. (2018) reference. Nakamura, M. M., Tasslimi, A., Lieu, T. A., Levine, O., Knoll, M. D., Russell, L. B., & Sinha, A. (2011). [Cost effectiveness of child pneumococcal conjugate vaccination in middle-income countries.](https://academic.oup.com/inthealth/article-lookup/doi/10.1016/j.inhe.2011.08.004)_International health_, _3_(4), 270-281. Ozawa, S., Clark, S., Portnoy, A., Grewal, S., Brenzel, L., & Walker, D. G. (2016). [Return on investment from childhood immunization in low-and middle-income countries, 2011–20.](https://www.healthaffairs.org/doi/full/10.1377/hlthaff.2015.1086?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed)_Health Affairs_, _35_(2), 199-207. Center, I. V. A. (2017). [The evidence base for pneumococcal conjugate vaccines (PCVs): data for decision-making around PCV use in childhood.](https://www.jhsph.edu/ivac/wp-content/uploads/2018/05/PCVEvidenceBase-Jan2017.pdf)_Baltimore (MD): Johns Hopkins University_. Goldblatt, D., Southern, J., Andrews, N. J., Burbidge, P., Partington, J., Roalfe, L., ... & Snape, M. D. (2018). [Pneumococcal conjugate vaccine 13 delivered as one primary and one booster dose (1+ 1) compared with two primary doses and a booster (2+ 1) in UK infants: a multicentre, parallel group randomised controlled trial.](https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30654-0/fulltext)_The Lancet Infectious Diseases_, _18_(2), 171-179. O'Brien, K. L. (2018). [When less is more: how many doses of PCV are enough?.](https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc)_ __The Lancet Infectious Diseases_, _18_(2), 127-128.{/ref} PCV vaccines include a limited subset of possible pneumococcal serotypes. The distribution of pneumococcal serotypes is known to vary between countries and PCV vaccines include the ones that are most common globally. Which non-vaccine serotypes are most common in a particular country, may affect the potential for a particular vaccine’s impact. However, not all countries collect data on serotype distribution, and an assessment of the potential impact is therefore compromised.{ref}Adegbola, R. A., DeAntonio, R., Hill, P. C., Roca, A., Usuf, E., Hoet, B., & Greenwood, B. M. (2014). [Carriage of Streptococcus pneumoniae and other respiratory bacterial pathogens in low and lower-middle income countries: a systematic review and meta-analysis](https://www.ncbi.nlm.nih.gov/pubmed/25084351). _PloS one_, _9_(8), e103293.{/ref} {ref}Megiddo, I., Klein, E., & Laxminarayan, R. (2018). [Potential impact of introducing the pneumococcal conjugate vaccine into national immunisation programmes: an economic-epidemiological analysis using data from India.](https://gh.bmj.com/content/3/3/e000636)_ BMJ global health_, _3_(3), e000636.{/ref} {ref}Johnson, H. L., Deloria-Knoll, M., Levine, O. S., Stoszek, S. K., Hance, L. F., Reithinger, R., ... & O'Brien, K. L. (2010). [Systematic evaluation of serotypes causing invasive pneumococcal disease among children under five: the pneumococcal global serotype project.](https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1000348)_PLoS medicine_, _7_(10), e1000348.{/ref} Notably, since the PCV vaccine was introduced, there has been a rise in pneumococcal invasive disease incidences caused by the less common serotypes. This suggests that, by reducing the prevalence of vaccine-included serotypes, the vaccine unintentionally provides space for non-vaccine serotypes, against which it works less well.{ref}World Health Organization. (2010). [Changing epidemiology of pneumococcal serotypes after introduction of conjugate vaccine: July 2010 report.](https://www.who.int/wer/2010/wer8543.pdf?ua=1)_ Weekly Epidemiological Record [Relevé épidémiologique hebdomadaire_], _85_(43), 434-436.{/ref} This means that the vaccine's effectiveness may decrease over time, if the serotype formulation of PCV is not continually reevaluated. In the future, new versions of pneumococcal vaccines may be needed that work better independently of the bacterial serotype. Such vaccines are already in development.{ref}Pichichero, M. E. (2017). [Pneumococcal whole-cell and protein-based vaccines: changing the paradigm](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277969/). _Expert review of vaccines_, _16_(12), 1181-1190.{/ref} {ref}Ginsburg, A. S., Nahm, M. H., Khambaty, F. M., & Alderson, M. R. (2012). Issues and challenges in the development of pneumococcal protein vaccines. Expert review of vaccines, 11(3), 279-285{/ref} ## Hepatitis B vaccine The chart here shows the coverage for Hepatitis B vaccination. Hepatitis B (HepB) is a highly contagious viral infection that attacks the liver and is transmitted through contact with the blood or other body fluids of an infected person. As the chart shows, it is estimated that about 100,000 people die each year of chronic liver disease due to hepatitis B. The WHO recommends that all infants should receive their first dose of vaccine as soon as possible after birth, preferably within 24 hours. <Chart url="https://ourworldindata.org/grapher/immunization-hepb3-of-one-year-old-children"/> ## Haemophilus influenzae type b vaccine Haemophilus influenzae type b (Hib) is a bacterial infection that causes meningitis and pneumonia transmitted through the respiratory tract from infected to susceptible individuals. The chart here shows the coverage for Hib vaccination. <Chart url="https://ourworldindata.org/grapher/hib-vaccine"/> ## Polio vaccine The chart here shows the coverage of the polio vaccine. Poliomyelitis (OPV, IPV) is a highly infectious viral disease. Once the poliovirus invades the nervous system it can cause irreversible paralysis in a matter of hours. No cure exists for polio, only treatment to alleviate symptoms. As we detail in our [entry on polio](https://owid.cloud/polio) the world is on its way to eradicate the disease thanks to the vaccine against the virus: While in the 1980s there were 350,000 paralytic cases of polio every year, the world saw only 42 cases in 2016. <Chart url="https://ourworldindata.org/grapher/polio-vaccine-coverage-of-one-year-olds"/> ## Tuberculosis vaccine (BCG) The chart here shows the coverage of the BCG vaccine, which protects against tuberculosis. Developed more than a century ago, bacille Calmette–Guérin vaccine (BCG) is currently the only vaccine available against tuberculosis (TB). Close to 4 billion people have been vaccinated with BCG - this makes it the most widely used vaccine in the world.{ref}Kendig, E. L., Wilmott, R. W., & Chernick, V. (2012). [_Kendig and Chernick's disorders of the respiratory tract in children_](https://www.sciencedirect.com/science/article/pii/B9780323448871000298). 9th ed. Elsevier Health Sciences.{/ref} BCG vaccine is based on a reduced-virulence strain of _Mycobacterium bovis_, a bacterium that is closely related to _Mycobacterium tuberculosis_ - the pathogen that causes TB. BCG vaccine was already used in the 1920s in Belgium and France in small trials and after the Second World War its use was expanded to vaccinate children across Europe. In 1950s the WHO started recommending the use of BCG globally. BCG is effective at protecting children and adolescents from severe forms of TB and meningitis.{ref} Rodrigues, L. C., Mangtani, P., & Abubakar, I. (2011).[ How does the level of BCG vaccine protection against tuberculosis fall over time?](https://www.bmj.com/content/343/bmj.d5974.full). _Bmj_, _343_, d5974.{/ref} {ref}Rodrigues, L. C., Diwan, V. K., & Wheeler, J. G. (1993). [Protective effect of BCG against tuberculous meningitis and miliary tuberculosis: a meta-analysis.](https://academic.oup.com/ije/article-abstract/22/6/1154/650235)_International journal of epidemiology_, _22_(6), 1154-1158.{/ref} However, studies have shown that the length of protection provided by the vaccine varies greatly depending on the populations studied: from 15 years in the UK to 50–60 years in Alaska.{ref}Sterne, J. A. C., Rodrigues, L. C., & Guedes, I. N. (1998).[ Does the efficacy of BCG decline with time since vaccination?.](https://www.ingentaconnect.com/content/iuatld/ijtld/1998/00000002/00000003/art00005)_The international journal of tuberculosis and lung disease_, _2_(3), 200-207.{/ref} {ref}Aronson, N. E., Santosham, M., Comstock, G. W., Howard, R. S., Moulton, L. H., Rhoades, E. R., & Harrison, L. H. (2004). [Long-term efficacy of BCG vaccine in American Indians and Alaska Natives: a 60-year follow-up study.](https://jamanetwork.com/journals/jama/article-abstract/198681)_Jama_, _291_(17), 2086-2091.{/ref} The reason for such variability is not clear, but factors such as different vaccine seed strains used for immunization and pre-existing immunity in people already exposed to other mycobacteria strains may be important. Notably, BCG vaccine does not protect people from primary infections, that is it does not prevent people from getting infected with _M. tuberculosis _bacterium in the first place. BCG also does not prevent activation of latent TB if a person has already been infected. Therefore, the vaccine has limited effect on prevention of _M. tuberculosis _spread in a population.{ref} https://www.who.int/biologicals/areas/vaccines/bcg/en/ {/ref} <Chart url="https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds"/> ## Yellow fever vaccine The chart here shows the coverage of the yellow fever vaccine. Yellow fever (YF) is a viral disease transmitted by infected mosquitoes. There are 40 countries and territories at risk for yellow fever in Africa and the Americas and of these 36 include yellow fever vaccination in their routine immunization schedules. Total, vaccine coverage in 2018 was estimated at 49%.{ref}[https://www.who.int/news-room/fact-sheets/detail/immunization-coverage](https://www.who.int/news-room/fact-sheets/detail/immunization-coverage){/ref} <Chart url="https://ourworldindata.org/grapher/yellow-fever-vaccine-coverage"/> --- # Definitions and Measurement --- ### Calculating coverage The coverage is calculated as the proportion of persons in a target age group who received a vaccine dose. Dates of vaccination are either taken from a child’s home-based record, recorded based on caregiver recall, or from health facility records. While appearing straightforward enough, several methodological problems of household survey respondent data on vaccination have been well documented.{ref}Daniel A. Salmon, Philip J. Smith, Ann Marie Navar, William K. Y. Pan, Saad B. Omer, James A. Singleton, Neal A. Halsey; Measuring Immunization Coverage among Preschool Children: Past, Present, and Future Opportunities, _Epidemiologic Reviews_, Volume 28, Issue 1, 1 August 2006, Pages 27–40, [https://doi.org/10.1093/epirev/mxj001](https://doi.org/10.1093/epirev/mxj001){/ref} Questions have arisen about how accurately parents can recall child immunization history and the limitations of phone calls to collect data. Even accurately estimating target populations in low-income settings can be difficult and discrepancies have been found when comparing country-reported figures with independent surveys.{ref}"Global childhood immunization coverage growing at only half the officially reported rate, IHME study" online here: [http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme](http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme){/ref} Furthermore, childhood vaccinations are rarely considered altogether. The DTP3 vaccination tends to be the vaccination most often used as a marker of strength in a country’s immunization programs, since three administrations of the vaccination are required.{ref}Other vaccines measured by the WHO and UNICEF are HepB3, Hib3, MCV and PAB.{/ref} ### National and subnational coverage National coverage rates are what is focused upon, but even when national coverage are high, subnational coverage can reveal inequities, which is why the WHO and UNICEF are increasing efforts to gather high quality subnational coverage data.{ref}See: [http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/](http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/){/ref} In 2015 coverage estimates at the district level were only reported for 158 of the 194 WHO Member States. National data only provides part of the picture of immunization coverage. Different levels of coverage data, including at sub-national or district level is useful for gaining an understanding of where there might be clusters of under- or un-vaccinated children. --- # Data Sources --- ### World Health Organization - Immunization surveillance, assessment and monitoring * **Data:** Immunization coverage, system indicators and schedule, and disease incidence * **Geographical coverage:** WHO member nations * **Time span:** 1980 onwards for many countries * **Available at:** Online [here](http://www.who.int/immunization/monitoring_surveillance/data/en/) ### UNICEF * **Data:** Percent of one-year-olds immunized * **Geographical coverage:** UN member nations * **Time span:** 1980 onwards for many countries * **Available at:** Online from UNICEF [here](http://web.archive.org/web/20150709064229/http://data.unicef.org/child-health/immunization). Also available via Gapminder [here](http://www.gapminder.org/data/) (search "vaccine" to find the data). ### Further reading More information about vaccines in general can be found on the World Health Organization (WHO) page on [immunization](http://www.who.int/topics/immunization/en/). <AllCharts heading="Interactive charts on vaccination"/> | { "id": 1455, "date": "2013-05-10T23:14:52", "guid": { "rendered": "http://localhost/wordpress/?page_id=1455" }, "link": "https://owid.cloud/vaccination", "meta": { "owid_publication_context_meta_field": [], "owid_key_performance_indicators_meta_field": { "raw": "* **14% of children** in the world do not receive basic vaccines.", "rendered": "<ul>\n<li><strong>14% of children</strong> in the world do not receive basic vaccines.</li>\n</ul>\n" } }, "slug": "vaccination", "tags": [], "type": "page", "title": { "rendered": "Vaccination" }, "_links": { "self": [ { "href": "https://owid.cloud/wp-json/wp/v2/pages/1455" } ], "about": [ { "href": "https://owid.cloud/wp-json/wp/v2/types/page" } ], "author": [ { "href": "https://owid.cloud/wp-json/wp/v2/users/18", "embeddable": true } ], "curies": [ { "href": "https://api.w.org/{rel}", "name": "wp", "templated": true } ], "replies": [ { "href": "https://owid.cloud/wp-json/wp/v2/comments?post=1455", "embeddable": true } ], "wp:term": [ { "href": "https://owid.cloud/wp-json/wp/v2/categories?post=1455", "taxonomy": "category", "embeddable": true }, { "href": "https://owid.cloud/wp-json/wp/v2/tags?post=1455", "taxonomy": "post_tag", "embeddable": true } ], "collection": [ { "href": "https://owid.cloud/wp-json/wp/v2/pages" } ], "wp:attachment": [ { "href": "https://owid.cloud/wp-json/wp/v2/media?parent=1455" } ], "version-history": [ { "href": "https://owid.cloud/wp-json/wp/v2/pages/1455/revisions", "count": 30 } ], "wp:featuredmedia": [ { "href": "https://owid.cloud/wp-json/wp/v2/media/38637", "embeddable": true } ], "predecessor-version": [ { "id": 53614, "href": "https://owid.cloud/wp-json/wp/v2/pages/1455/revisions/53614" } ] }, "author": 18, "parent": 0, "status": "publish", "content": { "rendered": "\n<div class=\"blog-info\">This article was first published in July 2015; last revised in October 2022.<br><em>We thank Stephanie Shendale, Sarah Loving, Anita Milicic, and Andy Pollard for helpful comments and suggestions on earlier draft versions of this entry.</em></div>\n\n\n\t<div class=\"wp-block-owid-summary\">\n\t\t<h2>Summary</h2>\n\t\t\n\n<p>Since the invention of the smallpox vaccine, vaccines have greatly reduced the prevalence of diseases everywhere in the world. This research article explains which vaccines are available and where they are, what their impact on global health is, and how the world can make more progress against early death and disease with the help of vaccines.</p>\n\n\n\n<ul><li><a href=\"#not-every-child-who-should-be-vaccinated-is-vaccinated\">Vaccination coverage has improved greatly over the past decades, but globally 13.5 million children were not vaccinated in 2018</a></li><li><a href=\"#vaccines-save-lives\">Vaccines are one of the most successful and cost-effective ways to prevent diseases</a></li><li><a href=\"#progress-made-with-vaccination\">Increased vaccine coverage has led to decline of diseases</a></li><li><a href=\"#public-support-and-skepticism\">9 out of 10 people in the world think that vaccinating children is important</a></li><li><a href=\"#coverage-impact-and-potential\">The coverage for many vaccines is still too low and we are missing out on saving many more lives</a></li></ul>\n\n\n\t</div>\n\n\n<h4>Related writing</h4>\n\n\n\n<ul><li><a href=\"https://ourworldindata.org/smallpox\">Smallpox</a> \u2014 How has vaccination eradicated smallpox?</li><li><a href=\"https://ourworldindata.org/eradication-of-diseases\">Disease eradication</a> \u2014 How and which diseases can be eradicated?</li><li><a href=\"https://ourworldindata.org/pneumonia#pneumococcal-vaccines\">Child & </a><a href=\"https://ourworldindata.org/child-mortality#\">infant</a><a href=\"https://ourworldindata.org/pneumonia#pneumococcal-vaccines\"> mortality</a> \u2014 What are children dying from and how can we prevent it?</li></ul>\n\n\n\n<h2>Not every child who should be vaccinated is vaccinated</h2>\n\n\n\n<h4>Global vaccine coverage</h4>\n\n\n\n<p>This chart shows the global vaccination coverage of one-year-olds with some of the most important vaccines recommended by the WHO. For many essential vaccines coverage is now much higher than 80%. However, the rates of vaccination are still not sufficient. </p>\n\n\n\n<p>If you click the play button you see that the coverage for most vaccines has increased substantially over time.</p>\n\n\n\n<p>The vaccine against diphtheria, tetanus and pertussis, is often used as the key metric for global vaccination coverage because it is a good indicator for access to routine immunization services. In 2018, coverage of the third dose of DTP was 86%. This means that out of 135 million under-one-year-olds more than 19 million did not receive full immunization. The coverage of the first dose of DTP was 90% indicating that <strong>13.5 million children were not vaccinated</strong> in 2018. </p>\n\n\n\n<p>In 2018, only 35% of children globally received the rotavirus vaccine, which protects children from <a href=\"https://ourworldindata.org/diarrheal-diseases\">diarrheal diseases</a> \u2014 <a href=\"https://ourworldindata.org/child-mortality#what-are-children-dying-from\">one of the leading causes</a> of child mortality. Similarly, pneumococcal vaccine that protects children from <a href=\"https://ourworldindata.org/pneumonia\">pneumonia</a> \u2014 the leading cause of child mortality \u2014 only reached 47% of one-year-olds.{ref}This and other numbers in this entry are based on the estimates by the World Health Organisation. The coverage estimates are calculated by dividing the total number of vaccinations given by the number of children in the target population. Target population size is usually based on census population projections.</p>\n\n\n\n<p>This means that there may be children in the target population that for medical reasons should be exempt from vaccination. These medical reasons may include factors such as allergies to vaccine components or severe immunodeficiencies. </p>\n\n\n\n<p>Notably, such cases are very rare and would have little effect on global coverage numbers. For example, <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4783279/\">a study</a> from 2003 identified severe allergic reaction in only 0.000063% of all vaccinations, that’s 0.63 cases per million vaccinations. In addition, vaccines are always being improved with fewer ingredients that may cause allergic reactions. </p>\n\n\n\n<p>Vaccination of children with immunodeficiencies generally needs to be assessed by a specialist. Especially, for vaccine that are based on a live pathogens. For example, <a href=\"https://www.who.int/immunization/policy/Immunization_routine_table1.pdf\">WHO recommends</a> vaccinating HIV-positive children with measles vaccine if child’s HIV infection is asymptomatic or not severe. Similarly, children with severe immunodeficiency syndrome (SCID), a genetic disorder that causes defects in immune system, are <a href=\"https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/severe-combined-immunodeficiency-scid\">safely vaccinated</a> with many vaccines before SCID is even diagnosed, but it’s recommended not to vaccinate them with live vaccines. </p>\n\n\n\n<p>In fact, one of the reasons it is important to increase vaccination rates is that those children and adults who for medical reasons cannot be vaccinated would still be protected from diseases through <a href=\"https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity\">herd immunity</a>.{/ref} </p>\n\n\n\n<blockquote class=\"wp-block-quote\"><p><strong>Related chart – the <em>number</em> of children vaccinated</strong>. <a href=\"https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds?time=1980..2015\">This chart</a> shows how many one-year-olds were vaccinated globally.</p></blockquote>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/global-vaccination-coverage\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h4>Prosperity and vaccination coverage</h4>\n\n\n\n<p>Why do not all children in the world receive vaccinations?</p>\n\n\n\n<p>This chart shows that it is in poor countries where vaccination coverage is low. The vaccine coverage against diphtheria, pertussis (whooping cough), and tetanus is a good marker of the strength of a country\u2019s immunization programs since several administrations are required. All rich countries have vaccination coverage rates of more than 90%. It is in low- and middle-income countries where coverage is low \u2013 in some countries below 50%.</p>\n\n\n\n<p>But the chart also shows that some poor countries \u2013 like Burundi, Rwanda, and Bangladesh \u2013 achieve high coverage rates. Similarly, countries in which a large share of the population is living in extreme poverty often \u2013 but not always \u2013 have lower immunization rates, as <a href=\"https://ourworldindata.org/grapher/vaccination-coverage-dpt-by-extreme-poverty?endpointsOnly=0\">this chart shows</a>.</p>\n\n\n\n<figure><iframe loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/vaccination-coverage-by-income-in\" width=\"300\" height=\"150\"></iframe></figure>\n\n\n\n<h2>Vaccines save lives</h2>\n\n\n\n<p>We know that vaccines save lives. But how many lives vaccines have they saved? </p>\n\n\n\n<p>The World Health Organisation (WHO) suggests that vaccination prevents 2-3 million deaths each year.{ref} <a href=\"https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage\">https://www.who.int/en/news-room/fact-sheets/detail/immunization-coverage</a>{/ref} However, while we are certain that vaccines have saved millions of lives, calculating a precise number is impossible. Also the quoted number from the WHO is in important ways a very low estimate.</p>\n\n\n\n<p>The counterfactual world, in which vaccines would have never been developed, would be so different that an estimate of the impact of vaccines is impossible. One example that makes this clear is to consider the impact of the smallpox vaccine: <a href=\"https://owid.cloud/smallpox\">Smallpox</a> was once an extremely common and deadly infectious disease, but it has been eradicated globally back in 1977 thanks to the vaccination against the disease. It is impossible to know exactly how many people would die of smallpox today if scientists had not developed the vaccine. Reasonable estimates are in the range of around 5 million lives per year, which implies that between 1980 and 2018 around 150 to 200 million lives have been saved.{ref}UNICEF (1996) and Hinman, A. R. (1998) estimate that in the absence of a vaccine the world would have seen 5 million deaths due to smallpox every year in the mid-1990s.</p>\n\n\n\n<p>Assuming that the estimate for the mid-1990s provides a midpoint estimate for the period since 1980 and therefore multiplying the 5 million per year estimate by the number of years between 1980 and 2018 means that since the eradication of the disease 190 million people\u2019s lives were saved.</p>\n\n\n\n<p>UNICEF (1996) \u2013 Vaccines bring 7 diseases under control. Online <a href=\"https://www.unicef.org/pon96/hevaccin.htm\">here</a>.{/ref} This makes clear why it is so difficult to estimate the number of lives saved every year and why the WHO estimate is rather low.</p>\n\n\n\n<h3>How vaccines work & herd immunity</h3>\n\n\n\n<p>The basic mechanism by which vaccines work is simple: Vaccines create immunity in an individual by introducing a weakened or killed form of the pathogen that make us ill \u2013 such as bacteria or viruses \u2013 or its toxins or one of its surface proteins. The vaccine induces acquired immunity so that when your body encounters the real disease-causing agent it is ready to mount a defense.</p>\n\n\n\n<p>There is a collective social benefit in a high vaccination coverage. For most diseases, the greater the proportion of people who are immunized, the better protected is everyone in the population as the disease transmission can be reduced or stopped. Herd immunity is a community protection that is created when a high percentage of the population is vaccinated, such that it less likely that the infectious disease spreads.{ref}See Oxford’s Vaccine Knowledge Project for an explanation here: <a href=\"http://vk.ovg.ox.ac.uk/herd-immunity\">http://vk.ovg.ox.ac.uk/herd-immunity</a>.{/ref}</p>\n\n\n\n<p>Herd immunity provides a protective barrier, especially also for those who <em>cannot</em> be vaccinated. These include vulnerable groups such as babies too young to be vaccinated or immune-compromised children who are the first potential victims of low vaccination rates.</p>\n\n\n\n<p>When a person is immune to a disease they can act as a barrier to slow down or prevent the transmission of disease to other people. When the number of people in a population that are immune against a disease is reached, such that a disease no longer persists in the population, this is called the <em>herd immunity threshold</em> (HIT). The table shows the HIT for several diseases. Measles and pertussis are highly contagious airborne diseases and a larger share of people need to be vaccinated to stop the transmission. Because of this these diseases have the highest HIT rates that need to be reached. For example, two doses of measles vaccination offers 99% protection, while in the absence of immunization, the lifetime risk of infection is nearly 100%.{ref}Beutels P, Van Damme P, Van Casteren V, Gay NJ, De Schrijver K, Meheus A. <em>The difficult quest for data on “vanishing</em>“<em>vaccine-preventable infections in Europe: the case of measles in Flanders</em> (<em>Belgium</em>). Vaccine. 2002 Oct 4;20(29-<br>30):3551-9 <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/12297401\">here</a>{/ref}</p>\n\n\n\n<h6>Herd Immunity Thresholds of vaccine-preventable diseases{ref}This table is taken from <a href=\"https://en.wikipedia.org/wiki/Herd_immunity\">Wikipedia’s entry on Herd Immunity</a>\u00a0\u2013 the original sources are listed there.{/ref}</h6>\n\n\n\n<table id=\"tablepress-77\" class=\"tablepress tablepress-id-77\">\n<thead>\n<tr class=\"row-1 odd\">\n\t<th class=\"column-1\">Disease</th><th class=\"column-2\">Transmission</th><th class=\"column-3\">Basic reproduction number</th><th class=\"column-4\">Herd Immunity Threshold</th>\n</tr>\n</thead>\n<tbody class=\"row-hover\">\n<tr class=\"row-2 even\">\n\t<td class=\"column-1\">Measles</td><td class=\"column-2\">Airborne</td><td class=\"column-3\">12\u201318</td><td class=\"column-4\">92\u201395%</td>\n</tr>\n<tr class=\"row-3 odd\">\n\t<td class=\"column-1\">Pertussis</td><td class=\"column-2\">Airborne droplet</td><td class=\"column-3\">12\u201317</td><td class=\"column-4\">92\u201394%</td>\n</tr>\n<tr class=\"row-4 even\">\n\t<td class=\"column-1\">Diphtheria</td><td class=\"column-2\">Saliva</td><td class=\"column-3\">6\u20137</td><td class=\"column-4\">83\u201386%</td>\n</tr>\n<tr class=\"row-5 odd\">\n\t<td class=\"column-1\">Rubella</td><td class=\"column-2\">Airborne droplet</td><td class=\"column-3\">6\u20137</td><td class=\"column-4\">83\u201386%</td>\n</tr>\n<tr class=\"row-6 even\">\n\t<td class=\"column-1\">Smallpox</td><td class=\"column-2\">Airborne droplet</td><td class=\"column-3\">5\u20137</td><td class=\"column-4\">80\u201386%</td>\n</tr>\n<tr class=\"row-7 odd\">\n\t<td class=\"column-1\">Polio</td><td class=\"column-2\">Fecal-oral route</td><td class=\"column-3\">5\u20137</td><td class=\"column-4\">80\u201386%</td>\n</tr>\n<tr class=\"row-8 even\">\n\t<td class=\"column-1\">Mumps</td><td class=\"column-2\">Airborne droplet</td><td class=\"column-3\">4\u20137</td><td class=\"column-4\">75\u201386%</td>\n</tr>\n<tr class=\"row-9 odd\">\n\t<td class=\"column-1\">SARS</td><td class=\"column-2\">Airborne droplet</td><td class=\"column-3\">2\u20135</td><td class=\"column-4\">50\u201380%</td>\n</tr>\n<tr class=\"row-10 even\">\n\t<td class=\"column-1\">Ebola</td><td class=\"column-2\">Bodily fluids</td><td class=\"column-3\">1.5\u20132.5</td><td class=\"column-4\">33\u201360%</td>\n</tr>\n<tr class=\"row-11 odd\">\n\t<td class=\"column-1\">Influenza</td><td class=\"column-2\">Airborne droplet</td><td class=\"column-3\">1.5\u20131.8</td><td class=\"column-4\">33\u201344%</td>\n</tr>\n</tbody>\n</table>\n\n\n\n\n<h2>Progress made with vaccination</h2>\n\n\n\n<p>In total there are now at least 28 human diseases against which we have effective vaccines.{ref}Cholera, Dengue fever, Diphtheria, Haemophilus influenzae type b, Hepatitis A, Hepatitis B, Hepatitis E, Human papilloma-virus, Influenza, Japanese encephalitis, Malaria, Measles, Meningococcal disease, Mumps, Pneumococcal disease, Pertussis, Poliomyelitis, Rabies, Rotavirus gastroenteritis, Rubella, Tetanus, Tick-borne encephalitis, Tuberculosis, Typhoid fever, Varicella, Yellow fever, Shingles (Herpes Zoster), and Smallpox.<br>See <a href=\"https://en.wikipedia.org/wiki/Vaccine-preventable_diseases\">https://en.wikipedia.org/wiki/Vaccine-preventable_diseases</a> and <a href=\"https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/\">https://www.who.int/immunization/global_vaccine_action_plan/GVAP_doc_2011_2020/en/</a>{/ref} The breakthrough that allowed us to get there was made in the late 18th century, the smallpox vaccine was the very first vaccine.</p>\n\n\n\n<h3>Smallpox and the origin of vaccination</h3>\n\n\n\n<p>Vaccination has a long history. An early form of vaccination was referred to as ‘variolation’ or more broadly as ‘inoculation’. Practised for a long time in Asia, this was an ancient technique of deliberate <a href=\"https://owid.cloud/smallpox\">smallpox</a> infection in which dried smallpox scabs were blown up the nose to infect the person with a form of the disease which was often milder. By the 1700s variolation had spread to Africa, India and the Ottoman Empire, followed by the UK and America, where the method of infection more frequently used was a puncture to the skin.</p>\n\n\n\n<p>Variolation did work, but there were large risks. Those variolated could contract the more severe form of smallpox and die, and they could also transmit the disease to others.</p>\n\n\n\n<p>In 1796 English physician Edward Jenner demonstrated another method of inoculation in which he relied on cowpox. Cowpox is a similar disease to smallpox and it had previously been observed that an infection with cowpox can protect against smallpox. Jenner conducted an experiment using matter from a cowpox lesion to inoculate his gardener\u2019s eight-year-old son James Phipps. Two months later Jenner exposed the boy to smallpox lesion matter and when Phipps did not develop smallpox he concluded that he was protected against the disease. Jenner called the procedure \u2018vaccination\u2019 after ‘vacca’ the Latin word for cow because of the origin of this first vaccination from the cowpox virus.</p>\n\n\n\n<p>Following the findings of Jenner as the first scientific attempt to control disease by vaccination, the smallpox vaccine went through many iterations, with the newer vaccines produced by modern cell culture techniques (passing the virus through cell culture makes the vaccine safer). By the middle of the 20th century confidence grew that smallpox could be the first disease that humankind might be able to eradicate. In 1967 the WHO launched a <a href=\"http://www.who.int/csr/disease/smallpox/vaccines/en/\">global eradication of smallpox program</a>. Mass vaccination of over 80% of a country’s population ensued but people who were nomadic or lived in politically unstable regions posed particular problems. A number of innovations came in the development of foot-powered injector called the <a href=\"http://www.who.int/csr/disease/smallpox/vaccines/en/\">\u201cped-o-jet\u201d and then the bifurcated needle</a>, which was efficient and cost-effective to use.</p>\n\n\n\n<p>In order to reach large sections of population, epidemiologist <a href=\"http://www.who.int/csr/disease/smallpox/vaccines/en/\">William Foege</a> developed Eradication Escalation (E2) to contain smallpox outbreaks during October (the seasonal low point of smallpox transmission where prevention of just few cases could stop a smallpox chain transmission). <a href=\"http://www.who.int/csr/disease/smallpox/vaccines/en/\">Other obstacles faced</a> included forcibly vaccinating an Indian religious leader to convince his followers to be vaccinated, negotiation of ceasefires for vaccine transport in war-torn Nigeria, vaccinating in concentric rings around an outbreak, and cash bounties to reward the reporting of smallpox cases. Finally in 1977 the last case of naturally contracted smallpox was reported in Somalia, in Ali Maow Maalin, and in 1980 the <a href=\"http://www.who.int/csr/disease/smallpox/vaccines/en/\">WHO announced that smallpox had been eradicated</a>. We cover the history of smallpox, including the vaccination and eradication, in more detail in our entry on <a href=\"https://owid.cloud/smallpox\">smallpox</a>.</p>\n\n\n\n<h3>Vaccine innovation</h3>\n\n\n\n<p>The chart here shows a timeline of innovation in the development of vaccines. Each bar begins in the year in which the pathogenic agent was first linked to the disease and the bar ends in the year in which a vaccination against that pathogen was licensed in the US.</p>\n\n\n\n<p>For some diseases there has been a relatively short timespan between when the infectious agent was linked to the disease and when a vaccine was developed. Before 2020 the quickest development was that for measles. The agent was linked to the disease in 1953 and the vaccine was licensed in the U.S. in 1963. In 2020 this record was broken when <a href=\"https://owid.cloud/covid-vaccinations\" data-type=\"page\" data-id=\"38102\">several vaccines</a> were developed within just one year to fight the <a href=\"https://owid.cloud/coronavirus\" data-type=\"page\" data-id=\"30223\">coronavirus pandemic</a>.</p>\n\n\n\n<p><a href=\"https://ourworldindata.org/malaria/\">Malaria</a> is proving harder as it has been over a century since the agent was linked to the disease. Alphonse Laveran discovered in 1880 that the Plasmodium parasite is the cause for malaria.{ref}See Francis EG Cox (2010) \u2013 History of the discovery of the malaria parasites and their vectors. In <em>Parasites and Vectors</em>. Online <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2825508/#!po=8.33333\">here</a>.{/ref}</p>\n\n\n\n<p>Early vaccines developed in the last several decades were insufficiently effective and until recently none of the scientific efforts led to a licensed vaccine. Recently there has been new hope for a malaria vaccine as we document in <a href=\"https://ourworldindata.org/malaria#a-vaccine-against-malaria\">the relevant section in our entry on malaria</a>.</p>\n\n\n\n<p>Vaccine innovation has followed both scientific and political-economic developments:</p>\n\n\n\n<ul><li>Bacterial culture techniques which allowed the development of bacterial vaccines for diphtheria, tetanus, and pertussis in the early 1900s.</li><li>The first and second world wars prompted combined efforts by universities, governments, and private companies.</li><li>By the 1950s viral tissue culture techniques allowed the development of vaccines against <a href=\"https://owid.cloud/polio\">polio</a>, measles, mumps, rubella, and varicella (chickenpox).</li><li>New technologies in molecular biology and advanced chemistry techniques have most recently led to vaccines against hepatitis B, influenza, and pneumococcus, which causes pneumonia and meningococus, which causes meningitis and septicaemia.</li></ul>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" width=\"3093\" height=\"2398\" src=\"https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart.png\" alt=\"\" class=\"wp-image-42922\" srcset=\"https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart.png 3093w, https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart-400x310.png 400w, https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart-709x550.png 709w, https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart-150x116.png 150w, https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart-768x595.png 768w, https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart-1536x1191.png 1536w, https://owid.cloud/app/uploads/2021/05/Vaccination-innovation-chart-2048x1588.png 2048w\" sizes=\"(max-width: 3093px) 100vw, 3093px\" /></figure>\n\n\n\n<p></p>\n\n\n\n<h3>Progress against vaccine-preventable diseases in the US</h3>\n\n\n\n<p>The visualization here shows the reduction in cases and deaths from vaccine-preventable diseases in the United States after the introduction of each vaccine. This data was published by Roush and Murphy (2007){ref}Roush and Murphy (2007) \u2013 Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155\u20132163. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/18000199\">here</a>{/ref} and the data can be viewed in a table <a href=\"https://ourworldindata.org/roush-and-murphy-2007-data/\">here</a>.</p>\n\n\n\n<p>For several diseases the US has achieved a 100% reduction of cases and deaths and for many other diseases the reduction is often very substantial as well.</p>\n\n\n\n<h6>Reduction of cases and deaths of vaccine-preventable diseases in the United States after the introduction of the vaccine.{ref}These data are taken from the research paper Roush and Murphy (2007) \u2013 Historical comparisons of morbidity and mortality for vaccine-preventable diseases in the United States. In the Journal of the American Medical Association, 298, 18, 2155\u20132163 <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/18000199\">here</a>.<br>\nThe vaccines against the diseases up till \u2018Tetanus\u2019 were vaccines licensed or recommended before 1980. The vaccines against the last 5 diseases were only licensed or recommended between 1980 and 2005.{/ref}</h6>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full\"><img loading=\"lazy\" width=\"2106\" height=\"2864\" src=\"https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths.png\" alt=\"\" class=\"wp-image-35037\" srcset=\"https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths.png 2106w, https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths-294x400.png 294w, https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths-404x550.png 404w, https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths-110x150.png 110w, https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths-768x1044.png 768w, https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths-1129x1536.png 1129w, https://owid.cloud/app/uploads/2020/07/Vaccine_Reduction-of-Cases-and-Deaths-1506x2048.png 1506w\" sizes=\"(max-width: 2106px) 100vw, 2106px\" /></figure></div>\n\n\n\n<h4>The development of the vaccine against measles and the history of measles in the US</h4>\n\n\n\n<p>The introduction of a vaccine was not the only reason for progress against these diseases, as the visualization shows. The case-fatality rates of measles was falling in high income countries such as the US prior to the introduction of the vaccine in 1960 \u2013 this is best seen by switching from the linear to the logarithmic axis. Improved living conditions, nutrition, and medical advancements meant that contracting measles was less and less likely to be fatal.</p>\n\n\n\n<p>The rate of cases however was virtually unchanged until after the measles vaccine was introduced \u2013 as our visualization shows.{ref}See also ‘Graphical proof that vaccines work (with sources)’ in <em>Medium</em> online <a href=\"https://medium.com/@visualvaccines/graphic-proof-that-vaccines-work-with-sources-61c199429c8c\">here</a>.</p>\n\n\n\n<p>To account for such long-term changes, Roush and Murphy (2007) report data from the period shortly before the introduction of the respective vaccine. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/18000199\">here</a>{/ref}</p>\n\n\n\n<p>A visualization showing the total number of cases and deaths can be seen <a href=\"https://ourworldindata.org/grapher/measles-cases-and-death\">here</a>.</p>\n\n\n\n<iframe loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/measles-cases-and-death-rate\" width=\"300\" height=\"150\"></iframe>\n\n\n\n<h3>Global decline in vaccine-preventable diseases</h3>\n\n\n\n<p><span style=\"font-weight: 400;\">The WHO estimates that </span><a rel=\"noopener noreferrer\" href=\"http://www.who.int/mediacentre/news/releases/2017/infants-worldwide-vaccinations/en/\" target=\"_blank\"><span style=\"font-weight: 400;\">2 to 3 million deaths</span></a><span style=\"font-weight: 400;\"> are prevented every year through immunization against diphtheria, tetanus, whooping cough, and measles.</span>{ref}In our graphics and visualizations we rely on the <em>Institute for Health Metrics</em> (IHME) \u2018<a href=\"http://ghdx.healthdata.org/gbd-results-tool\">Global Burden of Disease Study 2016</a>\u2019 estimates of child death rates from individual VPDs (compared with other causes), TB death rates across countries, and death rates from individual VPDs; this dataset extends back to 1990 and therefore provides a longer-term perspective on these changes over time. However, lack of estimates from the IHME on the role of vaccination in the prevention of deaths means we rely on WHO data for the number of deaths prevented each year through vaccination and the total amount of deaths VPDs are responsible for.</p>\n\n\n\n<p>The rates reported by the WHO and IHME are in a similar range but do differ slightly. WHO data on individual disease death rates can be found here: <a href=\"http://www.who.int/gho/mortality_burden_disease/en/\" target=\"_blank\" rel=\"noreferrer noopener\">http://www.who.int/gho/mortality_burden_disease/en/</a>{/ref}</p>\n\n\n\n<p><span style=\"font-weight: 400;\">Nonetheless, the WHO also estimates that VPDs are still responsible for </span><a href=\"http://www.who.int/mediacentre/commentaries/vaccine-preventable-diseases/en/\" target=\"_blank\" rel=\"noopener noreferrer\"><span style=\"font-weight: 400;\">1.5 million deaths</span></a><span style=\"font-weight: 400;\"> each year. </span></p>\n\n\n\n<p><span style=\"font-weight: 400;\">In the chart we see the global number of deaths of children younger than 5 years per year from 1990 to 2017. The number of deaths which are wholly or partially preventable by vaccines are shown in color.{ref}Note that, as discussed later in this post, the role of vaccines in prevention varies between these causes of death. Measles, for example, has the capacity to be eliminated through vaccination. Diarrheal deaths, in contrast, cannot be eliminated through vaccination alone; hygiene, water services, and nutrition must also be prioritised.{/ref} The chart shows that the reductions in child deaths over this 25-year period were primarily achieved by a reduction of the number of deaths from vaccine-preventable diseases: The decline in causes which are not vaccine preventable has been modest, while the number of child deaths caused by diseases for which vaccines are available declined from 5.1 million deaths in 1990 to 1.8 million deaths 27 years later.</span></p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><a href=\"https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019.png\"><img loading=\"lazy\" width=\"715\" height=\"550\" src=\"https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019-715x550.png\" alt=\"\" class=\"wp-image-23891\" srcset=\"https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019-715x550.png 715w, https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019-150x115.png 150w, https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019-400x307.png 400w, https://owid.cloud/app/uploads/2018/04/Reduction-of-child-deaths-due-to-vaccine-preventable-diseases-2019-768x590.png 768w\" sizes=\"(max-width: 715px) 100vw, 715px\" /></a></figure></div>\n\n\n\n<p><span style=\"font-weight: 400;\">Two vaccines are responsible for saving millions each year: \u2018DTP\u2019 against diphtheria, tetanus, and pertussis (whooping cough) and \u2018MMR\u2019 against measles, mumps, and rubella.{ref}Some countries only give measles vaccines combined with rubella (MR) or with varicella in addition (MMRV).{/ref} Before the measles vaccine was introduced in 1963, measles caused a large number of deaths globally, estimated at </span><a href=\"http://www.who.int/mediacentre/factsheets/fs286/en/\" target=\"_blank\" rel=\"noopener noreferrer\"><span style=\"font-weight: 400;\">2.6 million each year</span></a><span style=\"font-weight: 400;\">. Because about 86% of the </span><a href=\"http://www.who.int/mediacentre/factsheets/fs378/en/\"><span style=\"font-weight: 400;\">world population is immunized today,</span></a><span style=\"font-weight: 400;\"> the number of people killed by measles have been cut dramatically to an estimated 95,000 deaths in 2017. Tetanus and pertussis were also previously much bigger killers, with pertussis affecting especially children younger than 5 years and tetanus striking newborns (</span><a href=\"http://www.who.int/immunization/diseases/tetanus/en/\"><span style=\"font-weight: 400;\">killing an estimated 787,000 newborns</span></a><span style=\"font-weight: 400;\"> in 1988, compared with 49,000 in 2013</span><span style=\"font-weight: 400;\">).</span></p>\n\n\n\n<h4>The way ahead</h4>\n\n\n\n<p><span style=\"font-weight: 400;\">However, the gains in global vaccination coverage have slowed down slightly in the last few years. The WHO estimates that </span><a href=\"http://www.who.int/mediacentre/factsheets/fs378/en/\"><span style=\"font-weight: 400;\">19.5 million infants</span></a><span style=\"font-weight: 400;\"> worldwide are still at risk of VPDs because they miss out on basic vaccines.</span>{ref}Highlighted are 10 countries <a href=\"http://www.who.int/mediacentre/factsheets/fs378/en/\">where approximately 60%</a> of these infants live in: Angola, Brazil, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan, and South Africa.{/ref}</p>\n\n\n\n<p><span style=\"font-weight: 400;\">In addition, all the recommended doses of a vaccine need to be received for it to be most effective. In the case of measles three vaccine doses are recommended. Even though an estimated </span><span style=\"font-weight: 400;\">85% of children receive their first dose of the vaccine, <a href=\"http://www.who.int/mediacentre/factsheets/fs378/en/\" target=\"_blank\" rel=\"noopener noreferrer\">this drops to 64%</a> for the second dose.</span> <span style=\"font-weight: 400;\">Therefore, it is not only lack of vaccination that is a problem, but it is under-vaccination that leads to deaths from VPDs.</span></p>\n\n\n\n<p><span style=\"font-weight: 400;\">What then are the most deadly VPDs? Which diseases continue to kill the most people? </span></p>\n\n\n\n<h4>The most deadly diseases</h4>\n\n\n\n<p><b>Tuberculosis:</b><span style=\"font-weight: 400;\"> Determining which are the most deadly VPDs requires acknowledging that some vaccinations are more effective than others. While most vaccines included in national routine schedules are highly effective, a better vaccine for tuberculosis (TB) is desperately needed. It is Sub-Saharan Africa and parts of Asia in particular that <a href=\"https://ourworldindata.org/grapher/tuberculosis-death-rates\">are affected by TB</a>, as the world map shows.</span></p>\n\n\n\n<p><span style=\"font-weight: 400;\">The vaccine for TB \u2013 Bacillus Calmette\u2013Gu\u00e9rin (BCG) \u2013 has been in use for nearly 100 years. It protects against severe forms of TB but is </span><a rel=\"noopener noreferrer\" href=\"https://wellcome.ac.uk/news/world-immunisation-week-seven-vaccine-challenges\" target=\"_blank\"><span style=\"font-weight: 400;\">not effective against pulmonary TB</span></a><span style=\"font-weight: 400;\"> (in the lungs) and has variable effectiveness against TB in adults.</span>{ref}Zwerling A, Behr MA, Verma A, Brewer TF, Menzies D, Pai M. The BCG World Atlas: A Database of Global BCG Vaccination Policies and Practices. <em>PLoS Medicine</em>. 2011;8(3):e1001012. doi:10.1371/journal.pmed.1001012. Available <a href=\"http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001012\">here</a>.{/ref}<sup>,</sup>{ref}For a detailed commentary on why we do not yet have an effective TB vaccine see: Davenne T, McShane H. Why don\u2019t we have an effective tuberculosis vaccine yet?<em> Expert Review of Vaccines</em>. 2016;15(8):1009-1013. doi:10.1586/14760584.2016.1170599. Available <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4950406/\">here.</a>{/ref}</p>\n\n\n\n<p>Furthermore, resistance of antibiotics used to treat TB is increasing, meaning some people can no longer be cured by drugs. The estimated number of people in 2016 with <a href=\"http://www.who.int/features/qa/79/en/\"><span style=\"font-weight: 400;\">multi-drug resistant TB was 490,000</span></a><span style=\"font-weight: 400;\">. </span></p>\n\n\n\n<p><span style=\"font-weight: 400;\">The fact that there is not a fully effective vaccine and that antibiotic treatment is facing serious difficulties makes TB the most deadly VPD.</span></p>\n\n\n\n<p><span style=\"font-weight: 400;\">Meningococcal meningitis and hepatitis B are also deadly VPDs. </span></p>\n\n\n\n<p><b>Meningococcal Meningitis: </b><span style=\"font-weight: 400;\">Despite the introduction of <em>MenAfriVac</em> in 2010, an effective vaccine against the most common type of meningitis in that region, meningococcal meningitis killed almost 130,000 people in 2016. Many cases occur in the so-called \u2018meningitis belt\u2019 of sub-Saharan Africa, crossing from Senegal to Ethiopia. Not all the countries in the meningitis belt have implemented mass vaccination campaigns for <em>MenAfriVac</em> and also do not benefit from the expensive <em>MenACWY</em> vaccine introduced into richer countries to protect against other types of meningococcal meningitis.</span>{ref}An affordable <em>MenACWYX</em> vaccine is being developed to cover all the types of meningococcal disease (with the exception of meningitis B, which is available through a separate vaccine) and will also have the ability to be transported at higher temperatures. It is currently in phase 1 clinical trial, with the hope that it will be available for use in 2020\u20132022.{/ref}<sup>,</sup>{ref}See Meningococcal disease in the Middle East and Africa: Findings and updates from the Global Meningococcal Initiative, Borrow, Ray et al. <em>Journal of Infection</em>, Volume 75 , Issue 1 , 1 – 11. Available <a href=\"http://www.journalofinfection.com/article/S0163-4453(17)30114-7/abstract\">here</a>.{/ref}</p>\n\n\n\n<p><b>Hepatitis B:</b><span style=\"font-weight: 400;\"> The vaccine against hepatitis B is also very effective (</span><a rel=\"noopener noreferrer\" href=\"http://www.who.int/mediacentre/factsheets/fs141/en/\" target=\"_blank\"><span style=\"font-weight: 400;\">an estimated 95% effectiveness</span></a><span style=\"font-weight: 400;\"> in preventing disease), meaning increased vaccination could lead to a significant reduction in deaths. Still, global coverage of the hepatitis B vaccine is lagging. In 2015, while <a rel=\"noopener noreferrer\" href=\"http://www.who.int/mediacentre/factsheets/fs141/en/\" target=\"_blank\">84% coverage was reached</a> for the third dose of the vaccine, the coverage for the birth dose was only 39%. Estimates from mathematical models have shown that if infant coverage would reach 90%, and the first dose administered at birth, 84% of global hepatitis B-related deaths could be prevented.</span>{ref}Susan T Goldstein, Fangjun Zhou, Stephen C Hadler, Beth P Bell, Eric E Mast, Harold S Margolis; A mathematical model to estimate global hepatitis B disease burden and vaccination impact, <em>International Journal of Epidemiology</em>, Volume 34, Issue 6, 1 December 2005, Pages 1329\u20131339, <a href=\"https://doi.org/10.1093/ije/dyi206\">https://doi.org/10.1093/ije/dyi206</a>. Available <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/16249217\">here</a>.{/ref}</p>\n\n\n\n<h3>Eradication of diseases through vaccination</h3>\n\n\n\n<p>Eradication is the ultimate goal of vaccination against a disease.</p>\n\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://owid.cloud/eradication-of-diseases</link-url>\n <title>How do we eradicate diseases?</title>\n <content>\n\n<p>One of the greatest successes that we can imagine for humanity is the complete eradication of a disease. For one human disease \u2013 smallpox \u2013 this has actually been achieved. The disease was fully eradicated in 1980. For other diseases we are getting close, as we show in our entry on the eradication of disease.</p>\n\n</content>\n <figure><img width=\"768\" height=\"456\" src=\"https://owid.cloud/app/uploads/2018/04/Costs-of-controlling-vs-eradicating-a-disease-1-768x456.png\" class=\"attachment-medium_large size-medium_large\" alt=\"\" loading=\"lazy\" srcset=\"https://owid.cloud/app/uploads/2018/04/Costs-of-controlling-vs-eradicating-a-disease-1-768x456.png 768w, https://owid.cloud/app/uploads/2018/04/Costs-of-controlling-vs-eradicating-a-disease-1-150x89.png 150w, https://owid.cloud/app/uploads/2018/04/Costs-of-controlling-vs-eradicating-a-disease-1-400x238.png 400w, https://owid.cloud/app/uploads/2018/04/Costs-of-controlling-vs-eradicating-a-disease-1-750x446.png 750w\" sizes=\"(max-width: 768px) 100vw, 768px\" /></figure>\n </block>\n\n\n<h4>On the way to the eradication of polio</h4>\n\n\n\n<p>Polio is targeted for global eradication. This has become possible through the polio vaccine that was developed in 1955. The WHO estimates that in 2015, <a href=\"https://ourworldindata.org/polio/#polio-prevalence-in-the-developing-world-and-the-global-spread-of-the-polio-vaccine\">85% of infants around the world</a> received three doses of polio vaccine. And the number of paralytic polio cases have <a href=\"https://ourworldindata.org/polio/#the-number-of-reported-polio-cases-by-world-region\">decreased by over 99%</a> since the 1980s, from an estimated 350,000 to 400,000 paralytic cases per year to <a href=\"http://www.who.int/mediacentre/factsheets/fs114/en/\">22 reported cases in 2017</a>.</p>\n\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/polio/</link-url>\n <title>Polio</title>\n <content>\n\n<p>We present the empirical evidence on the effort to eradicate poliomyelitis in an entry entirely dedicated to polio.</p>\n\n</content>\n <figure><img width=\"768\" height=\"542\" src=\"https://owid.cloud/app/uploads/2017/10/the-number-of-reported-polio-cases-by-world-region-768x542.png\" class=\"attachment-medium_large size-medium_large\" alt=\"\" loading=\"lazy\" srcset=\"https://owid.cloud/app/uploads/2017/10/the-number-of-reported-polio-cases-by-world-region-768x542.png 768w, https://owid.cloud/app/uploads/2017/10/the-number-of-reported-polio-cases-by-world-region-150x106.png 150w, https://owid.cloud/app/uploads/2017/10/the-number-of-reported-polio-cases-by-world-region-400x282.png 400w, https://owid.cloud/app/uploads/2017/10/the-number-of-reported-polio-cases-by-world-region-750x529.png 750w, https://owid.cloud/app/uploads/2017/10/the-number-of-reported-polio-cases-by-world-region.png 2040w\" sizes=\"(max-width: 768px) 100vw, 768px\" /></figure>\n </block>\n\n\n<h4>Eradication of smallpox</h4>\n\n\n\n<p>While the benefits might possibly be forgotten as vaccine-preventable diseases have lost their threat thanks to the introduction of the vaccines it is still true that people around the world \u2013 including those in richer countries \u2013 continue to benefit from vaccinations.</p>\n\n\n\n<p>One of the greatest successes of global health is eradication of smallpox. Smallpox, which just decades ago killed several hundred thousand people every year was successfully eradicated in 1980 thanks to the global vaccination program.{ref}Smallpox is the only disease that affects humans which has been eradicated through vaccination. Rinderpest, a disease that affected cattle, has also been eradicated. Polio is getting close to being eradicated.{/ref}</p>\n\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://owid.cloud/smallpox</link-url>\n <title>Smallpox</title>\n <content>\n\n<p>You find more detail about the disease and its eradication in our entry on smallpox.</p>\n\n</content>\n <figure><img width=\"768\" height=\"542\" src=\"https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-768x542.png\" class=\"attachment-medium_large size-medium_large\" alt=\"\" loading=\"lazy\" srcset=\"https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-768x542.png 768w, https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-400x282.png 400w, https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-779x550.png 779w, https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-150x106.png 150w, https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-1536x1084.png 1536w, https://owid.cloud/app/uploads/2019/11/deaths-from-smallpox-per-1000-population-2048x1446.png 2048w\" sizes=\"(max-width: 768px) 100vw, 768px\" /></figure>\n </block>\n\n\n<h2>Public support and skepticism</h2>\n\n\n\n<h3>People do not know how well we actually do in global vaccination</h3>\n\n\n\n<p>Today vaccines protect millions of people around the world from infectious diseases. In this fight we are much, much further ahead than most people realize.</p>\n\n\n\n<p>The first chart shows the evidence for this misperception. In this chart we plotted the survey responses that people gave when they were asked <em>\u201cHow many of the world\u2019s 1-year old children today have been vaccinated against some disease?\u201d</em>. The correct answer was 85.8%; this is the share of 1-year olds that received the third dose of the combination vaccine that protects against Diphtheria, Tetanus, and Pertussis (whooping cough).</p>\n\n\n\n<p>But in all countries in which people were surveyed people were much too pessimistic about the global coverage. Americans think that only 35% of the world’s children are vaccinated, the true coverage is 50 percentage points higher.{ref}This survey result is in line with the finding of the <em>Gapminder Ignorance Project</em>, which studied Americans’ perception of global vaccination efforts. Just as in the Ipsos Mori survey, the answers that most Americans gave were far off from the truth.</p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><a href=\"https://ourworldindata.org/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage.png\"><img loading=\"lazy\" width=\"750\" height=\"396\" src=\"https://ourworldindata.org/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage-750x396.png\" alt=\"\" class=\"wp-image-15353\" srcset=\"https://owid.cloud/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage-750x396.png 750w, https://owid.cloud/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage-150x79.png 150w, https://owid.cloud/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage-400x211.png 400w, https://owid.cloud/app/uploads/2017/12/Ignorance-Test_Global-Measles-vaccination-coverage-768x406.png 768w\" sizes=\"(max-width: 750px) 100vw, 750px\" /></a></figure></div>\n\n\n\n<p>More information on the Gapminder ‘Ignorance Test’ can be found <a href=\"http://www.gapminder.org/ignorance/\">here</a>. The results for the US are <a href=\"http://www.gapminder.org/news/ignorance-survey-in-the-usa-2013/\">here on Gapminder’s site</a>.<br>\n{/ref}</p>\n\n\n\n<p>In Japan people were even more pessimistic and thought that only 18% were vaccinated. As it is often the case in questions on global development we again see that people in poorer countries have a <a href=\"https://owid.cloud/wrong-about-the-world\">more accurate view of the world</a>: in Kenya and Senegal people thought that vaccines reach around two thirds of all children in the world, but even these highest estimates are 20 percentage points too low.</p>\n\n\n\n<h6>We hugely underestimate global vaccination coverage{ref}<br>\nThe survey results are from Chris Jackson (2017) \u2013 Global Perceptions of Development Progress: \u2018Perils of Perceptions\u2019 Research\u2019, published by Ipsos MORI, 18 September 2017. Online <a href=\"https://www.ipsos.com/en/global-perceptions-development-progress-perils-perceptions-research\">here</a>.{/ref}</h6>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><a href=\"https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage.png\"><img loading=\"lazy\" width=\"404\" height=\"550\" src=\"https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage-404x550.png\" alt=\"\" class=\"wp-image-20057\" srcset=\"https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage-404x550.png 404w, https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage-110x150.png 110w, https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage-294x400.png 294w, https://owid.cloud/app/uploads/2018/08/Misperception-of-global-vaccination-coverage-768x1046.png 768w\" sizes=\"(max-width: 404px) 100vw, 404px\" /></a></figure></div>\n\n\n\n<h4>People\u2019s view on vaccination coverage is outdated by more than three decades</h4>\n\n\n\n<p>The chart here illustrates how outdated people’s answers are. Most individuals think that the global vaccination coverage today is as low as it was in the 1980s or even earlier.{ref}</p>\n\n\n\n<p><strong>Terminology: <em>vaccination</em> and <em>immunization</em></strong></p>\n\n\n\n<p>There is a technical difference between vaccination and immunization, as the National Health Service (NHS) <a href=\"http://www.shb.scot.nhs.uk/board/publichealth/immunisation.asp\">explains</a>: \u201cVaccination means having a vaccine \u2013 that is actually getting the injection, or nasal spray or oral vaccine. Immunization means both receiving a vaccine and then becoming immune to a disease\u201d. The distinction is made because in a very small number of those who are vaccinated the vaccination will not \u2018take\u2019 and therefore that vaccinated person will not be immunized (i.e. will not be immune to the disease). However, as this refers to a very small number of people both terms are often used interchangeably across the academic literature and in media reporting and we follow this convention in this entry.{/ref}</p>\n\n\n\n<p>The World Health Organization recommends routine vaccinations to prevent illness, death and disability from diseases including diphtheria, pertussis (whooping cough), tetanus, polio, measles, and hepatitis B.{ref}For the WHO recommendations see <a href=\"http://www.who.int/ith/vaccines/en/\">http://www.who.int/ith/vaccines/en/</a></p>\n\n\n\n<p>The Bacille Calmette-Guerin (BCG) vaccine for tuberculosis (TB) is recommended in countries where TB is common. BCG policies and practices have varied considerably across time and countries. The <a href=\"http://www.bcgatlas.org/\">BCG World Atlas</a> is an online resource that tracks these changes comprehensively.{/ref}</p>\n\n\n\n<p>We have created a <a href=\"https://ourworldindata.org/grapher/the-worlds-number-of-vaccinated-one-year-olds\">chart</a> that shows the absolute number of one-year-olds who have received the vaccinations.</p>\n\n\n\n<p>Where the biggest gap in vaccination lies is with all children being fully vaccinated and protected as much as possible from infectious diseases. Gavi, the Vaccine Alliance, has analysis that suggests only <a href=\"https://www.nature.com/articles/d41586-017-05923-8\">7% of infants in the 73 poorest countries are fully immunized (that is, receiving all doses of all recommended vaccines)</a>.</p>\n\n\n\n<h3>How many people support vaccination across the world?</h3>\n\n\n\n<p>The London-based research charity <em>The Wellcome Trust</em> published their <a href=\"https://wellcome.ac.uk/what-we-do/our-work/wellcome-global-monitor\">Wellcome Global Monitor</a> in 2019 on attitudes to science and major health challenges. It is the world\u2019s largest study of its kind, surveying over 140,000 people from over 140 countries. As part of the <em>Gallup World Poll</em>, the 30-question survey ran during 2018.{ref}It provides data on topics such as trust in science and scientists; trust in sources of information about health; public understanding of the word \u2018science\u2019; the intersection between religious teachings and science; and attitudes to vaccines. In this post, we focus on how attitudes to vaccination vary across the world.{/ref}</p>\n\n\n\n<p>The Wellcome Trust survey asked three core questions related to attitudes to vaccines: do people think that vaccines are important for children to have; do they think vaccines are safe; and do they believe vaccines are effective.</p>\n\n\n\n<h4>Most people in the world think vaccines are important for children to have</h4>\n\n\n\n<p>More than 9-in-10 people in the world (92%) think that vaccines are important for children to have.</p>\n\n\n\n<p>How support varies across the world is shown in the map. We see high support for vaccination across almost all countries. In most countries over 80% of respondents think child vaccination is important, in many countries it is over 90% who think so.</p>\n\n\n\n<p>There is a visible North-South divide in attitudes: support is highest across South Asia at 98%; 97% in South America; 94% in Northern Africa; and 92% in Southern Africa. Support is still high, but lower across North America (87%); Western Europe (83%) and Eastern Europe (80%).</p>\n\n\n\n<p>Of those surveyed in Venezuela, Palestine, Ethiopia and Northern Cyprus thought vaccines were most important: 100% were in favour.{ref}This is a stark result for Venezuela in particular (although perhaps unsurprising) since the availability and coverage of child vaccination <a href=\"https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1\">has fallen significantly</a> over the last few years.{/ref}</p>\n\n\n\n<figure><iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/share-agrees-vaccines-are-important-wellcome\"></iframe></figure>\n\n\n\n<h4>Most people in the world think vaccines are safe, but mistrust is high in some countries</h4>\n\n\n\n<p>Some parents may not agree for children to be vaccinated if they think vaccines are unsafe or could potentially cause side-effects which are worse than the benefits. How prevalent are these safety concerns?</p>\n\n\n\n<p>Globally, a small share of people disagree that vaccines are safe. Only 7% of respondents across the world said they \u201cstrongly disagree\u201d or \u201csomewhat disagree\u201d with the statement \u2018Vaccines are safe\u2019.</p>\n\n\n\n<p>In many countries these concerns are very low: in Bangladesh, for example, less than 1% disagree that vaccines are safe. In neighbouring India, only 2% disagree. We see this distribution across the world in the map.</p>\n\n\n\n<p>Trust in vaccines is not high everywhere. There are some clear outliers. The French were most skeptical: 1-in-3 disagreed that vaccines were safe. Many in neighbouring Switzerland and Belgium were also very skeptical: more than 20% disagreed. Other countries with high mistrust of vaccine safety were Gabon (26%); Togo (25%); Russia (24%); Austria (21%), and Iceland (21%).</p>\n\n\n\n<figure><iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/share-disagree-vaccines-are-safe-wellcome-trust\"></iframe></figure>\n\n\n\n<h4>Only 5% of respondents globally disagree that vaccines are effective but skepticism is much higher in some countries</h4>\n\n\n\n<p>In response to the statement \u2018Vaccines are effective\u2019, only 5% of respondents across all surveyed countries said they \u201cstrongly disagree\u201d or \u201csomewhat disagree\u201d. The vast majority of people do not think of vaccines as ineffective.</p>\n\n\n\n<p>But, as with the other surveyed questions, this varies significantly across countries. We see this in the map. In some countries, very few respondents disagreed: less than 1% in Bangladesh and Egypt; 2% in India and Ethiopia; and 3% in China, Germany and the UK.</p>\n\n\n\n<p>Liberia is most skeptical with 28% disagreeing that vaccines are effective. But skepticism was also high in France (18%); Namibia (16%); Nigeria (16%); and Peru (15%).</p>\n\n\n\n<figure><iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/share-disagrees-vaccines-are-effective\"></iframe></figure>\n\n\n\n<h4>In some countries many people are undecided on vaccination</h4>\n\n\n\n<p>The finding of the Wellcome Trust of mostly very positive attitudes towards vaccines \u2013 a health intervention that <a href=\"https://ourworldindata.org/vaccination#how-is-the-world-doing-in-its-fight-against-vaccine-preventable-diseases\">saves millions of lives</a> and <a href=\"https://ourworldindata.org/smallpox\">eradicated one of the worst diseases</a> humanity ever faced \u2013 is a very positive finding.</p>\n\n\n\n<p>But there is a concerning finding which is hidden when we look only at agreement and disagreement to the questions in the Global Monitor.</p>\n\n\n\n<p>Take Japan as one example. Only 66% of Japanese respondents thought vaccines were important for children to have \u2013 very low in comparison to other countries. But few disagreed that vaccines were safe (only 8%) and disagreed that they\u2019re effective (only 3%). If few people thought they were unsafe and ineffective, why would support for vaccines be so low?</p>\n\n\n\n<p>Many Japanese respondents did not answer either way. 28% answered \u201cneither agree nor disagree\u201d to <a href=\"https://ourworldindata.org/grapher/share-neither-agrees-disagrees-vaccines-important\">whether child vaccination is important</a>; 55% to the question regarding the <a href=\"https://ourworldindata.org/grapher/share-neither-agree-disagree-vaccines-are-safe\">safety of vaccines</a>; and one-third were undecided on their effectiveness. It’s difficult here, without further questions, to fully interpret the opinions of those in this undecided category: maybe they had no opinion; or they thought vaccines could be safe or effective in some cases, but not all; or some vaccines were safe but others were not. With this data, it’s impossible to fully understand their reasoning.</p>\n\n\n\n<p>This stance was common across several other countries, as we see in the map.</p>\n\n\n\n<figure><iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/share-neither-agrees-nor-disagrees-vaccines-effective\"></iframe></figure>\n\n\n\n<p>While being undecided or divided is perhaps less concerning than denialism on the importance, safety and effectiveness of vaccination, it nonetheless suggests that many are unaware of the massive role vaccines have played in <a href=\"https://ourworldindata.org/vaccination#eradication-of-diseases-through-vaccination\">eradicating diseases</a>, and <a href=\"https://ourworldindata.org/vaccination#diseases-preventable-through-vaccination\">saving lives across the world</a>. The success story of vaccines is one we don\u2019t tell often enough.</p>\n\n\n\n<p>It\u2019s also true that people in the ‘neither’ group may be more likely to be convinced by arguments that are put forward by those who deny the safety, effectiveness and importance of vaccination.</p>\n\n\n\n<p>In a <a href=\"http://ourworldindata.org/vaccine-skepticism\"><strong>related post</strong></a>\u00a0we take a look at why denialism around vaccination exists, and what is effective in addressing it.</p>\n\n\n\n<h3>Does vaccine skepticism affect immunization coverage?</h3>\n\n\n\n<p>The crucial question to ask when considering the importance of vaccine skepticism is: does it actually have an effect on behaviour? Does it really affect the share of children who are vaccinated?</p>\n\n\n\n<p>In the chart we see the comparison of vaccination rates \u2013 here as the share of children who were immunized against diphtheria, pertussis and tetanus (DTP) in 2015, the latest year available \u2013 to the share of respondents in a given country who disagreed that vaccines are safe.</p>\n\n\n\n<p>You can also <a href=\"https://ourworldindata.org/grapher/immunization-measles-vs-vaccine-safety\">see this relationship</a> for measles vaccine coverage.</p>\n\n\n\n<p>Overall we see that widespread public concern for vaccine safety does not appear to be strongly correlated with vaccination rates. While one-third of the French public disagrees with their safety, 97% of children in France are vaccinated.</p>\n\n\n\n<p>There are numerous other reasons, however, why vaccination rates in some countries are low: in low-to-middle income countries the availability, affordability and access to vaccines can be poor. Having low coverage rates often doesn\u2019t reflect the population\u2019s view of them. As the chart shows, in many poor countries the situation is the opposite as in France: the vast majority of the population considers vaccine safe, but only about every second child receives the DTP vaccine.</p>\n\n\n\n<p>One country which stands out is Ukraine: there we see that vaccination rates are uncharacteristically low for <a href=\"https://ourworldindata.org/grapher/gdp-per-capita-worldbank\">its income level</a> \u2013 less than 1-in-4 children receive the DTP vaccine. Skepticism of vaccine safety in Ukraine is high at 15%.</p>\n\n\n\n<p>Is there evidence that skepticism is reflected in cases and deaths from vaccine-preventable diseases? Over the last few years there has been <a href=\"https://www.who.int/csr/don/06-may-2019-measles-euro/en/\">a reported rise</a> in the number of measles cases in countries which had previously been close to eliminating the disease. In Europe, for example, there were more than <a href=\"https://www.who.int/csr/don/06-may-2019-measles-euro/en/\">34,000 cases of measles</a> in the first two months of 2019 alone. Ukraine <a href=\"https://www.who.int/csr/don/06-may-2019-measles-euro/en/\">accounted for the majority</a> (more than 70%) of these cases. And here as well as in Albania and Romania some measles cases led to the death of children.</p>\n\n\n\n<figure><iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/perception-of-the-safety-of-vaccines-vs-vaccine-coverage\"></iframe></figure>\n\n\n\n<div class=\"wp-block-columns\">\n<div class=\"wp-block-column\">\n<p>The visualization shows the relationship between the share of people who trust doctors and nurses in their country and share who disagree that vaccines are safe. Overall we see that countries with higher levels of distrust in the safety of vaccines tend to also have less trust in health professionals.</p>\n\n\n\n<p>There are however some outliers: France has relatively high trust in health staff, but are most mistrusting of vaccine safety.</p>\n\n\n\n<p>Health officials are worried that skepticism of vaccination will begin to translate to lower vaccination rates. One reason being attributed to higher skepticism is the spread of misinformation on social media.</p>\n\n\n\n<p>Social media firms do have a responsibility for dealing with misinformation and need to consider how to react carefully. Currently, social and online media companies are being asked by politicians in the US and UK to ban or control anti-vaccination messaging. Banning or strict control could reduce the exposure to such messages but does not solve the root problem: the public are asking questions about vaccines and are looking to find answers online. A worry is that banning certain sorts of information and groups will fuel suspicion and only drive activity elsewhere.</p>\n\n\n\n<p>Nonetheless, demands on social media firms to act is increasing. A request for action by <a href=\"https://schiff.house.gov/news/press-releases/schiff-sends-letter-to-google-facebook-regarding-anti-vaccine-misinformation\">Adam Schiff to the CEOs of Google and Facebook</a> sparked a cascade of responses. In an open letter, he asked for action against vaccine misinformation and similar demands have been made since, from the UK Health Secretary Matt Hancock among others.</p>\n</div>\n\n\n\n<div class=\"wp-block-column\">\n<figure><iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/trust-healthcare-vs-vaccine-safety\"></iframe></figure>\n</div>\n</div>\n\n\n\n<p></p>\n\n\n\n<h2>Vaccine policy</h2>\n\n\n\n<h3>What determines if vaccinations are compulsory?</h3>\n\n\n\n<p>Countries vary in whether vaccination is compulsory, mandatory (required according to specific mandates), or voluntary. Navin and Largent (2017) provide a helpful distinction between these policies. A compulsory policy is when refusing vaccination is illegal, while mandatory vaccination when certain goods and services are limited for not vaccinating.{ref}Navin M. Largent, improving non-medical exemption vaccine policies: three case studies. Public Health Ethics. 2017; 10: 225\u2013234. Available <a href=\"https://philpapers.org/rec/NAVINV\">here</a>{/ref}</p>\n\n\n\n<p>Which policy is followed has depended much on historical legacy, which becomes clear when one considers some of the different regulations and their history around the world:</p>\n\n\n\n<p><em>Compulsory vaccination:</em> Many Eastern Bloc countries introduced compulsory vaccination during the communist era. Vaccination was previously compulsory in Romania for example and after a drop in vaccination rates the country is going through the process of reintroducing compulsory vaccination. The same is true for Italy and also France, which had compulsory vaccination for three diseases but increased this number to 11 in January 2018 in response to a drop in vaccination rates.</p>\n\n\n\n<p><em>Mandatory vaccination:</em> Some countries, such as the United States, have mandates for vaccination where a child is required to be vaccinated to enter state school or daycare. An early case in the US paved the way for state jurisdiction to protect public health in light of personal liberty.{ref}See: <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/\">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1449224/</a>{/ref} In Jacobson v. Massachusetts (1905) the Supreme Court ruled that states have the authority to require vaccination against smallpox during a smallpox epidemic. Since then the US has had a history of school vaccination requirements. The increased number of children in public schools as a result of the compulsory school attendance law led to an increased risk of smallpox outbreaks, through close contact in large crowded classrooms.{ref}Stern, M., Alexandra. (2010). Better Off in School: School Medical Inspection as a Public Health Strategy During the 1918-1919 Influenza Pandemic in the United States{/ref} Similarly in Australia two policies penalize parents for not vaccinating their children. The ‘No jab no play’ policy removed unvaccinated children from state-sponsored childcare. The 2016 ‘No jab no pay’ policy removes state welfare by not providing the universal ‘Family Allowance’ welfare payments for parents who are conscientious objectors of vaccination.</p>\n\n\n\n<p><em>Voluntary vaccination:</em> Some countries where vaccination is voluntary had early pushback against vaccination, as in the UK and the Netherlands. In 1853 a law was passed in England and Wales requiring universal vaccination against smallpox, but opposition from anti-vaccinationists led to laws being passed to allow for conscientious objection.{ref}Amin, A.N.E., Parra, M.T., Kim-Farley, R. et al. (2012) \u2013 Ethical Issues Concerning Vaccination Requirements. In <em>Public Health Reviews</em> (2012) 34: 14. <a href=\"https://doi.org/10.1007/BF03391666\">https://doi.org/10.1007/BF03391666</a>. Online here: <a href=\"https://link.springer.com/article/10.1007/BF03391666\">https://link.springer.com/article/10.1007/BF03391666</a>{/ref}</p>\n\n\n\n<p><em>Vaccination requirements for country entry:</em> For countries in Africa and South America where yellow fever is endemic or where the mosquito vector is present a certificate of proof of vaccination is required. Only then will the country issue a visa upon entry to that country to prevent importation of this disease (particularly if travellers come from, or have visited other yellow fever endemic areas).{ref}See: <a href=\"http://www.who.int/csr/ihr/icvp/en/index.html\">http://www.who.int/csr/ihr/icvp/en/index.html</a>{/ref} In past centuries (17th to 19th), yellow fever was transported to North America and Europe, causing large outbreaks that disrupted economies and development, and in some cases decimated populations. Throughout the 18th and 19th century, yellow fever was among the most feared diseases in the ports of the Old and New World. Saudi Arabia is the only country that requires the <a href=\"http://www.who.int/ith/updates/20170408/en/\">additional vaccinations of meningococcal disease and polio</a> for pilgrims visiting Mecca.</p>\n\n\n\n<h4>Does it work to make vaccinations compulsory?</h4>\n\n\n\n<p>Whether compulsory vaccination results in improved vaccination rates is not a straightforward question to tackle because it is highly dependant on country context, historical circumstance, cultural and social norms, as well as the practicalities of implementing and enforcing such a law. </p>\n\n\n\n<p>Certainly in <a href=\"https://theconversation.com/despite-scepticism-europe-has-high-vaccination-rates-but-it-shouldnt-be-complacent-75169\">Eastern Bloc countries</a> when the vaccination law was compulsory, vaccination rates have been high but it is unclear whether to attribute this to the law or the behaviours and mechanisms of compliance under communist rule. Certain vaccinations have historically been compulsory such as smallpox, polio, and yellow fever. Here vaccination rates have also been high but it also encouraged organised opposition to vaccination and public discontent. This is a major concern for public health authorities that a relationship of trust, between governments and citizens is threatened (particularly for health where a rhetoric of self-responsibility, personalisation, and choice is encouraged). </p>\n\n\n\n<p>There are countries with high vaccination rates without compulsory vaccination and governments do not want to disrupt public trust and self-responsibility by making vaccination compulsory, particularly if it is not seen as needed. It has been argued that high coverage has been achieved through “other approaches or efforts” and so acceptance of compulsory vaccination might be problematic in countries such as Sweden, Norway, Denmark, the Netherlands, and the UK.{ref}Salmon, Daniel A et al., Compulsory vaccination and conscientious or philosophical exemptions: past, present, and future, The Lancet, Volume 367, Issue 9508, 436 – 442{/ref} </p>\n\n\n\n<p>In recent years governments have acted in response to epidemics to make vaccinations compulsory, as we have seen for 2017-18 with compulsory vaccinations in France, Italy, Germany, and Romania.</p>\n\n\n\n<p>One country where we can see the effect of variation in vaccination policy is the US. In the US states decide what vaccine exemptions are permitted for children who receive education in schools or use daycare. Public schooling unfortunately means that schools are sites of epidemics for childhood diseases, which is the reason such vaccination laws are required.</p>\n\n\n\n<p>In individual states exemptions are granted for medical reasons but many states also allow for philosophical, personal belief or religious exemptions. Only three states \u2013 Mississippi, West Virginia, and California \u2013 only allow for medical exemption. <a href=\"https://ourworldindata.org/app/uploads/2017/11/Screen-Shot-2017-11-10-at-15.31.35.png\">Californian immunization rates have increased</a> following a new Senate Bill SB 277 in 2015 to remove non-medical exemptions to vaccination. </p>\n\n\n\n<p>The chart here shows vaccination coverage and what exemptions are allowed for each state. Fewer exemptions generally mean higher vaccine coverage. Indeed, Mississippi does often top the list as having the highest vaccination rates because only medical exemptions are allowed in the state. But starkly, Mississippi residents are also consistently the <a href=\"http://www.businessinsider.de/unhealthiest-states-in-the-us-health-rankings-2017-12?r=US&IR=T\">unhealthiest</a> and <a href=\"https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/\">poorest</a> in the entire country. Health outcomes are very poor and many residents cannot afford healthcare (<a href=\"https://mississippitoday.org/2017/09/14/mississippi-still-worst-poverty-household-income-u-s/\">the state has the highest percentage without health insurance in 2017</a>). So perhaps it is unsurprising that residents accept subsidized vaccinations that are required for access to childcare and state schools.</p>\n\n\n\n<h6>Vaccination coverage of children, by US state in 2016/17{ref}The data source for vaccination coverage: School Vaccination Assessment Report, 2016-17 school year.<br> Estimated vaccination coverage with 5 doses of Childhood Diphtheria toxoid, Tetanus toxoid, acellular Pertussis (DTaP) vaccination for kindergartners (typical age range is 4\u20136 years).<br><br>The data source for exemptions is: Immunization Action Coalition, “Exemptions Permitted for State Immunization Requirements,” 2017; LexisNexis; StateNet 2017<br><br>Regarding the school vaccination coverage and exemption methods the source notes: “Each school year, school nurses, other school personnel, or health department personnel check the vaccination and exemption status of kindergartners enrolled in public and private schools as required by state law or regulation. State and local immunization programs measure vaccination coverage among children entering kindergarten annually. This may be done for every student or for a sample of students.<br><br>State and local areas set the vaccination requirements. Immunization information systems (IISs) may be used as one source of data for school vaccination assessment. The school-level data are reported to the health department. The aggregate data are reported to CDC for public and private schools. Data for home-schooled students are not routinely reported to CDC.”<br><br>The types of permitted exemptions vary by state. For specific details refer to <a href=\"https://www.cdc.gov/vaccines/imz-managers/coverage/schoolvaxview/requirements/index.html\">School Vaccination Requirements and Exemptions</a>.{/ref}</h6>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><a href=\"https://ourworldindata.org/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1.png\"><img loading=\"lazy\" width=\"521\" height=\"550\" src=\"https://ourworldindata.org/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1-521x550.png\" alt=\"\" class=\"wp-image-15521\" srcset=\"https://owid.cloud/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1-521x550.png 521w, https://owid.cloud/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1-142x150.png 142w, https://owid.cloud/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1-379x400.png 379w, https://owid.cloud/app/uploads/2017/12/DTP-Vaccination-rate-by-US-State-and-exemption-status-1-768x811.png 768w\" sizes=\"(max-width: 521px) 100vw, 521px\" /></a></figure></div>\n\n\n\n<h3>Vaccine supply</h3>\n\n\n\n<p>Supply constraints have caused problems for country access to vaccination. One-third of 194 countries have run out of a vaccine for a month or longer \u2013 according to <a href=\"http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health\">data</a> submitted to WHO and UNICEF \u2013 and this includes both high- and low-income countries. In the US, the Centers for Disease Control and Prevention (CDC) <a href=\"https://www.cdc.gov/vaccines/hcp/clinical-resources/shortages.html\">stated</a> that reasons for shortages were multi-factoral and included “…companies leaving the vaccine market, manufacturing or production problems, and insufficient stockpiles”. In 2018, it <a href=\"http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health\">was reported</a> that shortages where supplies of vaccines were critically low included those that target yellow fever, hepatitis B, cholera, meningitis C, diphtheria, whooping cough, tetanus, hepatitis A, and tuberculosis.</p>\n\n\n\n<p>Concerns about the supply of vaccines in an epidemic or pandemic have been raised. For example, the supply of yellow fever vaccine was limited for the outbreak in Angola in 2016 leading to the recommendation of a fractional dose to extend existing supplies.{ref}See the WHO <a href=\"http://www.who.int/emergencies/yellow-fever/mediacentre/qa/en/\">here</a>.{/ref}</p>\n\n\n\n<p><a href=\"http://foreignpolicy.com/2018/01/16/the-answers-are-out-there-natural-disasters-china-north-korea-corruption-economy/#health\">Laurie Garrett argues</a> that because the drug had become so cheap (60 cents for each vaccine 2008) few companies had an incentive to produce it and world stocks of the vaccine were nearing zero, forcing the WHO to dilute donated vaccines from countries like Brazil (which sent 18 million doses) by 5 to 1 with the hope they would still be sufficiently effective. Romania experienced a situation of parallel vaccine exports in 2016 where more vaccines were exported than was supplied to meet the country’s needs. A shortage of the measles, mumps, and rubella (MMR) vaccine was partly responsible for the measles outbreak in 2016-17.{ref}See <a href=\"https://www.euractiv.com/section/health-consumers/news/romania-cuts-vaccine-exports-as-measles-outbreak-takes-hold/\">here</a>.{/ref}</p>\n\n\n\n<p>In Venezuela, a country experiencing an economic crisis, there are severe <a href=\"https://www.bbc.co.uk/news/resources/idt-sh/Venezuela_bridge\">shortages of medicines, including vaccines</a>, which has led to an <a rel=\"noopener noreferrer\" href=\"https://www.reuters.com/article/us-venezuela-health/one-million-unvaccinated-venezuelan-kids-vulnerable-in-measles-outbreak-doctors-idUSKCN1C42Z1\" target=\"_blank\">estimated one million</a> unvaccinated children and the re-emergence of diseases such as diphtheria and measles.</p>\n\n\n\n<h3>The cost of vaccines</h3>\n\n\n\n<p>There are five big pharmaceutical companies{ref}According to MacKenzie, D. (2011) \u2013 Vaccines enjoy a healthy return. <em>New Scientist</em>. Available <a href=\"https://www.newscientist.com/article/dn20877-vaccines-enjoy-a-healthy-return/\">online</a>.{/ref} that account for 80% of vaccine production: Sanofi Pasteur, GlaxoSmithKline, Merck, Pfizer, and Novartis.{ref}In 2014 their vaccine business was acquired by GlaxoSmithKline, as reported <a href=\"https://www.telegraph.co.uk/finance/newsbysector/pharmaceuticalsandchemicals/11444023/GSK-and-Novartis-complete-deals-to-reshape-both-drugmakers.html\">here</a>.{/ref}</p>\n\n\n\n<p>Many vaccines are only provided by one or two suppliers. For newer vaccines there are often particularly few suppliers due to the high investment needed to develop a vaccine.{ref}There are exceptions however. A vaccine for tetanus and diphtheria (td) for example, has a large number of suppliers (13, and 7 for the paediatric formulation).{/ref} As one would expect from competition, the WHO reports that when vaccines are produced by a greater number of suppliers it leads to a decline of the prices of those vaccines.{ref}Review of vaccine price data. Submitted by WHO European Region Member States through the WHO/UNICEF. Joint Reporting Form for 2013. Online <a href=\"http://www.euro.who.int/__data/assets/pdf_file/0009/284832/Review-vaccine-price-data.pdf?ua=1\">here</a>.{/ref}</p>\n\n\n\n<p class=\"p2\">In the past vaccines were often viewed as less profitable products for pharmaceutical companies, which led to a lack of investment and some companies pulling out of production altogether.{ref}The Economist. (2010). A smarter jab. Available <a href=\"http://www.economist.com/node/17258858#print\">online</a>{/ref}</p>\n\n\n\n<p>But this has changed as the revenue of the global vaccines market has increased and richer country governments and insurance companies have been willing to pay more for new vaccines.</p>\n\n\n\n<p class=\"p2\">In addition, growing economies such as India and China are investing more in vaccines as well as developing their domestic manufacturing capacity. Poorer countries now have Gavi to help governments pool resources and make advance purchase commitments.{ref}The Economist. (2010). A smarter jab. Available <a href=\"http://www.economist.com/node/17258858#print\">online</a>{/ref}</p>\n\n\n\n<p>Gavi is an international organisation created in 2000 to bring together public and private sectors, with the goal of equal access to new and underused vaccines for children in poorer countries. It subsidizes vaccines that otherwise would not be affordable for low-income countries. In addition to subsidizing vaccines themselves, Gavi offers <a href=\"https://www.gavi.org/about/programme-policies/health-system-and-immunisation-strengthening-support-framework/\">vaccine introduction grants</a>, which help to cover the costs of introduction of new vaccines into routine immunization schedules. The map here shows which countries are eligible for GAVI support. </p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/gavi-supported-countries\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<p>Some vaccines still remain expensive. For example, the pertussis vaccine is available in two versions: whole cell (wP) containing the whole pertussis bacterium or acellular (aP) which contains a part of the pertussis bacterium. The pertussis vaccine is often combined with diphtheria and tetanus to produce either a DTwP or DTaP vaccine.{ref}See WHO guidance for more information at: <a href=\"https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf\">https://www.who.int/vaccine_safety/initiative/tools/DTP_vaccine_rates_information_sheet.pdf</a>{/ref}</p>\n\n\n\n<cite class=\"iUh30\"><br></cite>\n\n\n\n<p>DTaP is slightly more expensive; it is sometimes called ‘the painless vaccine’ because it causes less of a local reaction and pain but should not be given to children over the age of seven. However, DTwP has been shown to be more efficacious at preventing the transmission and spread of disease to unvaccinated people and to those with weak immunity.</p>\n\n\n\n<p>New vaccines tend to be more expensive as they are under patent protection. For example when the HepB vaccine was developed many lower income countries could not afford to pay $30 per dose.{ref}Jaffe, A. B., Lerner, J., Stern, S., & National Bureau of Economic Research. Innovation Policy and the Economy Group. (2006). <em>Innovation policy and the economy</em>. MIT Press. <a href=\"https://books.google.co.uk/books/about/Innovation_Policy_and_the_Economy.html?id=9I7KowFvI9oC&source=kp_cover&redir_esc=y\">here</a>{/ref}</p>\n\n\n\n<p>Today there is often a differentiation between the prices paid by countries as shown in the small table.</p>\n\n\n\n<h6>Price differences for vaccines between the US and developing countries{ref}The source of the data is the <a href=\"http://mshpriceguide.org/en/home/\">International drug price indicator guide</a>{/ref}</h6>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"\"><tbody><tr><td><strong>Vaccine</strong></td><td><strong>Cost per dose in a developing country</strong></td><td><strong>Cost per dose in the US</strong></td></tr><tr><td>HepB</td><td>$0.58 – 13.20</td><td>$50 – 100</td></tr><tr><td>BCG</td><td>$0.16 – 1.11</td><td>$100 – 200</td></tr><tr><td>Yellow fever</td><td>$4.30 – 21.30</td><td>$50 – 100</td></tr></tbody></table></figure>\n\n\n\n<h3>Which countries include vaccines in their immunization schedules?</h3>\n\n\n\n<div class=\"wp-block-columns\">\n<div class=\"wp-block-column\">\n<p>Several vaccines, including rubella, mumps, and rotavirus, are included in immunization schedules in many countries around the world. This means these vaccines are provided and recommended through routine services.</p>\n\n\n\n<p>This doesn’t necessarily tell us how many children <em>receive</em> these vaccines in each country. The vaccines may or may not be mandatory and their coverage rates may vary widely. Similarly, when countries do not have a vaccine in their schedule, this does not mean that the vaccine is completely unavailable in those countries, as it may be optional or available commercially.</p>\n\n\n\n<p>In the chart you can see which countries include rubella vaccines in their national immunization schedules. Rubella vaccines became available for the first time in 1969, starting in the United States, where it was developed.{ref}Lanziera, T., Haber, P., Icenogle, J. P., & Patel, M. (n.d.). Rubella. In <em>Epidemiology and Prevention of Vaccine-Preventable Diseases</em>. Communication and Education Branch, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention.<a href=\"https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html\"> https://www.cdc.gov/vaccines/pubs/pinkbook/rubella.html</a>{/ref} It was included in the schedules of the United States and most European countries as early as 1994 (the first year of this dataset). Over time, more countries included it in their schedule.</p>\n\n\n\n<p>But this took many years for some countries: for example, it took until 2018 for it to be included in countries such as Uganda and Congo.</p>\n\n\n\n<p>As of 2021 some countries, such as Nigeria and South Africa, still do not include it in their schedules.{ref}World Health Organization. (2021). <em>New and underutilized vaccines introduction</em>.<a href=\"https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html\"> https://immunizationdata.who.int/pages/indicators-by-category/new_and_under_utilized_vaccines_introduction.html</a>{/ref}</p>\n\n\n\n<p>In the links below, you can see these charts for other vaccines.</p>\n</div>\n\n\n\n<div class=\"wp-block-column\">\n<iframe src=\"https://ourworldindata.org/grapher/rubella-vaccine-immunization-schedule\" loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n</div>\n</div>\n\n\n\n<div class=\"wp-block-columns\">\n<div class=\"wp-block-column\"></div>\n\n\n\n<div class=\"wp-block-column\"> <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/haemophilus-influenzae-b-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/hepatitis-b-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/hepatitis-b-birth-dose-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/human-papillomavirus-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/inactivated-poliovirus-vaccine-immunization-schedule</link-url>\n <title></title>\n <content>\n\n<p></p>\n\n</content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/mcv2-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/mumps-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/pneumococcal-conjugate-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block>\n\n <block type=\"prominent-link\" style=\"is-style-thin\">\n <link-url>https://ourworldindata.org/grapher/rotavirus-vaccine-immunization-schedule</link-url>\n <title></title>\n <content></content>\n <figure></figure>\n </block></div>\n</div>\n\n\n\n<h3>Why do vaccine schedules differ?</h3>\n\n\n\n<h4>The chickenpox example</h4>\n\n\n\n<p>Chickenpox (varicella) is an example of a vaccine that some countries adopt into their routine childhood vaccination schedules, while others do not. The question that follows is why there is a difference in opinion for introducing widespread uptake of a vaccine or not. Japan was one of the first countries to adopt universal chickenpox vaccination.{ref}Bonanni et al. 2009; Bonanni P., Breuer J., Gershon A., Gershon M., Hryniewicz W., Papaevangelou V., et al. (2009) \u2013 Varicella vaccination in Europe – taking the practical approach. BMC Med 7: 26 <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/19476611\">here</a>.{/ref}</p>\n\n\n\n<p>Australia, Canada, Germany, Qatar, Republic of Korea, Saudi Arabia, Taiwan, Uruguay, U.S., Italy (Sicily only) and Spain (Madrid only) followed afterwards and adopted universal chickenpox vaccination. When extreme cases of chickenpox have occurred there have been calls for the vaccine to become <a href=\"http://www.bbc.co.uk/news/uk-england-cambridgeshire-36952432\">available for free</a> through the National Health Service in the UK. However, most European countries do not vaccinate against chickenpox, except for ‘at risk’ groups. The main reason for not adopting universal vaccination is the high cost. Additional supporting justifications are that it is usually a <a href=\"http://www.nhs.uk/chq/Pages/1032.aspx?CategoryID=62\">mild disease</a> and the benefit of fewer cases of shingles \u2013 as explained <a href=\"https://theconversation.com/everything-you-need-to-know-about-chickenpox-and-why-more-countries-dont-use-the-vaccine-63473\">here</a>.</p>\n\n\n\n<p>The Centers for Disease Control and Prevention in the US ran the <a href=\"https://www.cdc.gov/chickenpox/surveillance/vasp.html\">Varicella Active Surveillance Project</a> (VASP) from 1995 through to 2010 to monitor the impact of the varicella vaccination program and the key finding is shown in the chart. The coverage of the vaccine in Los Angeles County rose from 37.9% in 1997 to 95.1% in 2010, and in Philadelphia from 41.2% in 1997 to 94.6% in 2010 (one-dose vaccinations for children between 19 and 35 months of age). By 2010, varicella incidence declined by 98% in Antelope Valley (California) and West Philadelphia (Pennsylvania) compared with 1995. Outbreaks and hospitalizations also decreased rapidly. From 1995 to 1998, hospitalization rates ranged from 2.2 to 3.3 per 100,000 population but by 2006-2010 this had declined to 0.2 per 100,000 in Antelope Valley and 0.5 per 100,000 in Philadelphia.</p>\n\n\n\n<p>Chickenpox is an example that can also help to answer the question of whether better hygiene or vaccination are in fact responsible for the reduced rates of disease. Although both are important, a more recently adopted vaccination such as chickenpox can demonstrate the effects of vaccination in reducing the rate of disease after the importance of hygiene was discovered and became a preventative measure against disease. As hygiene standards already reached high levels, the additional benefit of the vaccine is confirmed. The impact on disease rates demonstrate it is not hygiene but vaccination that reduced the incidence of chickenpox so dramatically in the US.</p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"786\" height=\"550\" src=\"https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-786x550.png\" alt=\"\" class=\"wp-image-28812\" srcset=\"https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-786x550.png 786w, https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-400x280.png 400w, https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-150x105.png 150w, https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-768x538.png 768w, https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-1536x1075.png 1536w, https://owid.cloud/app/uploads/2019/12/Chickenpox-cases-in-US-2048x1434.png 2048w\" sizes=\"(max-width: 786px) 100vw, 786px\" /></figure>\n\n\n\n<h3>Which countries have mandatory childhood vaccination policies?</h3>\n\n\n\n<p>With the widespread rollout of <a href=\"http://ourworldindata.org/covid-vaccinations\">COVID-19 vaccines</a> globally, some countries have started to consider mandatory vaccination, although no country has yet to make vaccines mandatory for its population.{ref}Gostin, L. O., Salmon, D. A. and Larson, H. J. (2021) \u2018Mandating COVID-19 Vaccines\u2019, <em>JAMA</em>. American Medical Association, 325(6), p. 532. doi: 10.1001/jama.2020.26553.{/ref} While COVID-19 has resurfaced the debate on vaccination policies, it has been an important topic for many other diseases. The World Health Organization (WHO) estimates that vaccines save two to three million lives each year (excluding COVID). The development of vaccines against vaccine-preventable childhood diseases has been a key driver in the decline of <a href=\"http://ourworldindata.org/child-mortality\">child mortality</a>.</p>\n\n\n\n<p>Despite it being such an important topic, it is surprising that information about which countries have mandatory vaccine policy is lacking, and it is childhood vaccines under a country\u2019s national immunization schedules that are most commonly made mandatory.</p>\n\n\n\n<p>In this article we present a new global dataset which looks at childhood vaccination policies across the world.</p>\n\n\n\n<h3>How do childhood vaccination policies vary across the world?</h3>\n\n\n\n<p>We recently charted mandatory childhood vaccine policies worldwide as they are becoming an increasingly important policy intervention for governments trying to address low vaccination rates.{ref}Vanderslott, S., & Marks, T. (2021). <a href=\"https://www.sciencedirect.com/science/article/pii/S0264410X21005478\">Charting mandatory vaccination policies worldwide</a>. <em>Vaccine</em>.{/ref}</p>\n\n\n\n<p>The term \u2018mandatory\u2019 and \u2018mandates\u2019 are taken to mean quite different things across countries. Whilst the term is commonly used it is poorly defined.{ref}Attwell, K. and C. Navin, M. (2019) \u2018Childhood Vaccination Mandates: Scope, Sanctions, Severity, Selectivity, and Salience\u2019, <em>The Milbank Quarterly</em>, 97(4), pp. 978\u20131014. doi: 10.1111/1468-0009.12417.{/ref} Mandates require vaccination for a certain purpose, most commonly related to school entry for children. While definitional disagreements still persist, it remains important to better understand what policies are in place across countries and the reasons driving changes in policy over time.</p>\n\n\n\n<p>Our list indicates whether a country has a mandatory vaccination policy for one or more vaccine and the strictness of the mandate on a scale ranging across three levels: mandatory, mandatory for school entry, or recommended. The childhood vaccines include the vaccines that protect from <a href=\"https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide\">measles,</a> mumps, rubella, <a href=\"https://ourworldindata.org/grapher/immunization-coverage-against-diphtheria-tetanus-and-pertussis-dtp3-vs-gdp-per-capita\">diphtheria, tetanus, pertussis</a>, <a href=\"https://ourworldindata.org/grapher/polio-rate-of-cases-vs-vaccination-coverage\">polio</a>, rabies, hepatitis B, <a href=\"https://ourworldindata.org/rotavirus-vaccine\">rotavirus</a>, <a href=\"https://ourworldindata.org/grapher/hib-vaccine\">haemophilus influenzae type B</a>, and <a href=\"https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds?country=~OWID_WRL\">tuberculosis</a> \u2013 some of which are administered as combined vaccines. We have classified a country as having a mandatory policy if they mandate for at least one vaccine. </p>\n\n\n\n<p>The differences in vaccination policy across the world are shown in the map. By covering 149 countries we could identify some trends around where and why vaccines are mandatory today.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/mandatory-childhood-vaccination\" loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\t<block type=\"help\">\n\t\t<content>\n\n<h4></h4>\n\n\n\n<p><em>Note: this is a live dataset that relies on crowdsourcing to note policy changes. If you are aware of any new policies or policy changes for any country please do get in touch at: [email protected].</em></p>\n\n</content>\n\t</block>\n\n\n<h3>How do mandatory vaccination policies vary by region?</h3>\n\n\n\n<p>We found that assessing policies across WHO regions \u2013 European, Americas, Western Pacific, African, and Eastern Mediterranean \u2013 was a useful way to break down our analysis of policies worldwide.</p>\n\n\n\n<p>In the chart you see a breakdown of the number of countries with a given policy mandate. You can view this by region by using the “Change region” toggle on the interactive chart.</p>\n\n\n\n<p>Europe has a mixture of mandatory and recommended policies. But most European countries \u00ad\u2013 16 out of 28 \u2013 do not have mandatory vaccination. European countries were among the first to introduce mandatory vaccination for smallpox in the early 19<sup>th</sup> century, which also led to early push-back. The early introduction and early push-back, along with present-day approaches to foster mutual trust and responsibility between citizens and the health authorities, may be part of the reason why vaccination is often recommended rather than mandated in many European countries.{ref}Stuart Blume (2017) <em>Immunization: How Vaccines became Controversial – Stuart Blume – Google Books</em>. Reaktion Books.{/ref} Countries of the former-USSR (Union of Soviet Socialist Republics) or under the influence of the Eastern Bloc previously had mandatory vaccination, and many kept this policy in the post-USSR era.</p>\n\n\n\n<p>Most countries in the Americas \u2013 29 out of 35 \u2013 have mandatory vaccinations. In the USA, vaccination is regulated by individual states though it is mandatory for school entry in all of them. In Canada, only three provinces have legislated mandatory vaccination policies that apply to children enrolling in school.</p>\n\n\n\n<p>In the Western Pacific region, changes to mandatory policies have gone in both directions. Some countries such as Singapore have moved towards mandatory vaccinations whilst others, such as South Korea transitioned away from mandatory to recommended vaccines in 1999. For other countries, mandatory policies are more ambiguous. In China, there is no evidence of specific legislation mandating vaccines, despite many references to such claims in the literature.{ref}Attwell, K., Drislane, S. and Leask, J. (2019) \u2018Mandatory vaccination and no fault vaccine injury compensation schemes: An identification of country-level policies\u2019, <em>Vaccine</em>. Elsevier Ltd, 37(21), pp. 2843\u20132848. doi: 10.1016/j.vaccine.2019.03.065.{/ref}</p>\n\n\n\n<p>It was difficult to obtain information about vaccination policies across African countries, suggesting the absence of specific policies in the region. However, the policies we did find were for mandatory vaccination.</p>\n\n\n\n<p>Most countries in the Eastern Mediterranean region have mandatory vaccines. Israel is an exception in only recommending vaccination, based on a vaccination schedule outlined by the National Immunization Technical Advisory Group.</p>\n\n\n\n<p>There are a number of countries in South-East Asia with mandatory vaccination. India is similar to other large countries, with varying policies on mandatory vaccination at the state level. Finally, we note that there are some countries that have mandatory policies at a sub-country level such as in Canadian provinces and Indian and Australian states but we have classified these countries as to the national policy and the policies cover most of the country.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/number-countries-mandatory-vaccination?country=~OWID_WRL\" loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>What drives the introduction of mandatory vaccinations?</h3>\n\n\n\n<p>Overall, we found that the occurrence of recent outbreaks is a major factor in the introduction of mandatory vaccination, particularly for high and upper-middle-income countries in Europe. Germany, for example, made measles vaccination mandatory for school and day-care attendance in 2020 following large outbreaks.{ref}Rezza, G. (2019) \u2018Mandatory vaccination for infants and children: the Italian experience\u2019, <em>Pathogens and Global Health</em>. Taylor and Francis Ltd., pp. 291\u2013296. doi: 10.1080/20477724.2019.1705021.{/ref} Similarly, Serbia tightened mandatory vaccination laws following a measles outbreak in 2014 to 2015 by introducing harsher penalties.{ref}Pejin LS. Tightening measures for compliance with vaccination in Serbia ESPN Flash Report. European Commission; 2016.{/ref} Trends of reported cases of measles can be explored in detail <a href=\"https://ourworldindata.org/grapher/reported-cases-of-measles?country=~DEU\">here</a>.</p>\n\n\n\n<p>Secondly, many low- and lower-middle-income countries have resorted to mandatory vaccination policies because of a lack of other policy options. Nonetheless, many have still missed their target vaccination rates due to problems with vaccine supply, delivery, and access. In Guyana for example, vaccination is mandatory, yet vaccination coverage is hindered by the management of the supply chain in keeping storage temperatures consistent and the distribution of freeze-sensitive vaccines.{ref}UNICEF. Guyana Situation Analysis of Children and Women; 2016. Available at: <a rel=\"noreferrer noopener\" href=\"https://www.unicef.org/sitan/\" target=\"_blank\">https://www.unicef.org/sitan/</a> [accessed: 10 April 2020].{/ref} In Nigeria, vaccination is mandatory, and several states have enacted legislation criminalising vaccine refusal. Yet as Onyemelukwe (2016) argues, there are structural, logistical, political, systemic, religious and cultural obstacles to the effective distribution and uptake of vaccines, ranging from cold chain issues, to corruption and security issues.{ref}Onyemelukwe, C. (2016) \u2018Can legislation mandating vaccination solve the challenges of routine childhood immunisation in Nigeria?\u2019, <em>Oxford University Commonwealth Law Journal</em>. Taylor and Francis Ltd., 16(1), pp. 100\u2013124. doi: 10.1080/14729342.2016.1244450.{/ref} There is thus often variation between vaccination in policy compared to in practice.</p>\n\n\n\n<p>These findings will be useful to inform policymakers considering the merits of mandatory vaccination:</p>\n\n\n\n<p>1) In the past, an outbreak of a disease (such as measles) has led to introduction of mandatory vaccines even in countries where previously all vaccinations were recommended;</p>\n\n\n\n<p>2) Making a vaccine mandatory should not be the only policy tool but needs to be combined with strong access and availability of vaccines;</p>\n\n\n\n<p>3) It is not just a matter of whether to mandate a vaccine, but how this mandate will be enforced, whether people will comply, and the impact on state-citizen relations. </p>\n\n\n\n<p>In summary, mandatory vaccination must be considered with caution. A country\u2019s past experience with mandates, vaccination services, ability for enforcement, public attitudes, and the current state of disease outbreaks will all play a part in whether mandatory vaccination should be introduced.</p>\n\n\n\n<h2>Coverage, Impact, and Potential</h2>\n\n\n\n<h3>Diseases preventable through vaccination</h3>\n\n\n\n<p>The chart shows the number of global deaths caused by some of the most common and serious vaccine-preventable diseases.</p>\n\n\n\n<p>By selecting \u2018change country\u2019 it is possible to see this change for any country in the world and extending the timeline will let you see the change in deaths over time.</p>\n\n\n\n<p>There are more diseases for which vaccines are available now and even more are under development currently. The WHO publishes list of <a href=\"http://www.who.int/immunization/diseases/en/\">26 diseases</a> for which vaccines are available \u2013 including Japanese encephalitis, pneumococcal disease, varicella/chicken pox, HPV, Hepatitis A and rotavirus.</p>\n\n\n\n<iframe loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/Deaths-caused-by-vaccine-preventable-diseases-over-time\" width=\"300\" height=\"150\"></iframe>\n\n\n\n<h3>Diphtheria, Tetanus, and Pertussis vaccine</h3>\n\n\n\n<p>Diphtheria, tetanus, and pertussis are all bacterial diseases and a combination vaccine against all three diseases is commonly used. </p>\n\n\n\n<ul><li>Diphtheria primarily infects the throat and upper airways and is fatal in 5 \u2013 10% of cases.</li><li>Tetanus is not passed person-to-person but through spores of a bacteria living in soil and animal intestinal tracts. These bacteria enter the body through wounds and release a toxin that affects the nerves, which causes muscle stiffness and spasms.</li><li>Pertussis is a highly contagious disease of the respiratory tract, commonly known as whooping cough. Children who contract pertussis tend to have coughing spells that last four to eight weeks, but the highest fatality is in young infants. Vaccinating health workers and pregnant women is the most effective strategy for preventing disease in infants too young to be vaccinated. </li></ul>\n\n\n\n<p>The chart shows the progress over time of DTP3 immunization coverage of children around the world. By clicking on any country you can see the change in that country over time.</p>\n\n\n\n<p>The WHO <a href=\"https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=OWID_WRL\">reports</a> in 2017 that 85% of infants worldwide (116.5 million infants) received 3 doses of diphtheria-tetanus-pertussis vaccine (DTP3). Also in 2016 130 countries had reached at least 90% coverage with the DTP3 vaccine.{ref}See the WHO here: <a href=\"http://www.who.int/mediacentre/factsheets/fs378/en/\">http://www.who.int/mediacentre/factsheets/fs378/en/</a>{/ref}</p>\n\n\n\n<p>If we look at <a href=\"https://ourworldindata.org/grapher/share-of-children-immunized-dtp3?tab=chart&country=East%20Asia%20%26%20Pacific+Europe%20%26%20Central%20Asia+Latin%20America%20%26%20Caribbean+Middle%20East%20%26%20North%20Africa+North%20America+South%20Asia+Sub-Saharan%20Africa\">the change over time by world region</a> it is South Asia in particular that stands out. While 85% of one-year-olds today are immunized, that same figure was as low 6% in 1980.</p>\n\n\n\n<p>Within each country there can be substantial differences in vaccination coverage. The <a href=\"http://www.who.int/gho/urban_health/services/dpt3_vaccination/en/\">WHO reports</a> that in all regions children in the richest 20% of urban households are more likely to get immunized than children from the poorest 20% of households.</p>\n\n\n\n<p>Some countries lag behind however. Ukraine stands out as having particularly low DTP vaccination rates in 2015 of 23%, falling from 98% in 1999. Ed Holt writing for the Lancet in 2013 attributed the decline to: “A combination of public mistrust in vaccinations, poor vaccine supply, and corruption in the health system”.{ref}Holt, Ed., Ukraine at risk of polio outbreak, The Lancet , Volume 381 , Issue 9885 , 2244 <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/23819156\">here</a>{/ref} Therefore Ukraine is suffering from a combination of factors effecting vaccination rates from public attitudes and systemic delivery problems. Furthermore, the unrest since 2014 and Russian military intervention is likely to have worsened matters. Today only Equatorial Guinea reports even lower rates at 16%. As <a href=\"https://www.hrw.org/world-report/2015/country-chapters/equatorial-guinea\">Human Rights Watch observes</a>, very little of the country’s wealth is being directed towards the needs of citizens.</p>\n\n\n\n<p>The number of under-vaccinated children in Nigeria remains high, with <a href=\"http://www.gavi.org/library/news/statements/2017/vaccine-progress-in-developing-countries-in-danger-of-stalling/\">3.4 million children going without the DTP3 vaccine (compared with 2.9 million in India</a>).</p>\n\n\n\n<iframe loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/share-of-children-immunized-dtp3\" width=\"300\" height=\"150\"></iframe>\n\n\n\n<h3>Measles vaccine</h3>\n\n\n\n<p>Measles is a highly contagious virus-caused disease that, despite a safe and effective vaccine being available, infects thousands of people globally. Around 90,000 people die because of measles every year, the huge majority of whom (87%) are children younger than 5. Measles vaccination has resulted in an 84% drop in measles deaths between 2000-2016.{ref}Figures are updated by the WHO here: http://www.who.int/news-room/fact-sheets/detail/measles{/ref}</p>\n\n\n\n<p>The world map shows the share of children vaccinated with the first dose of measles vaccine.</p>\n\n\n\n<p>You can switch to the ‘chart’ view to see the global coverage against vaccines. The measles vaccine was developed in 1963. In 1983 \u2013 the first year for which global data is available \u2013 only every second child was vaccinated against measles. In the latest data this share has increased to 85% globally up from 72% in 2000.{ref}See the WHO here: <a href=\"http://www.who.int/mediacentre/factsheets/fs286/en/\">http://www.who.int/mediacentre/factsheets/fs286/en/</a>{/ref}</p>\n\n\n\n<p>The sub-Saharan African region achieves the lowest measles vaccination rates, along with conflict-ridden and unstable countries (e.g. Syria, Afghanistan, and Iraq). But also some of the Pacific Islands \u2013 such as Papua New Guinea and Vanuatu \u2013 are performing poorly.</p>\n\n\n\n<p>Today (data from 2014) 114.3 million children are vaccinated against measles every year, which is on average 313,071 children every single day.{ref}In 2014 there were <a href=\"https://ourworldindata.org/grapher/number-of-one-year-olds\">135.2 million one-year olds</a>. Of these <a href=\"https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles?tab=chart\">84.52% received the vaccine against measles</a>.<br> This means that 135.2 *0.8452 = 114.27 million children were vaccinated.{/ref}</p>\n\n\n\n<iframe loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles\" width=\"300\" height=\"150\"></iframe>\n\n\n\n<h4>Second dose of measles vaccine provides greater protection</h4>\n\n\n\n<p>As of 2018, the WHO estimate that 171 countries had included a second dose as part of routine immunization. Two doses are needed for a higher level of protection.{ref}Gaston De Serres, Jill Sciberras, Monika Naus, Nicole Boulianne, Bernard Duval, and Louis Rochette (1999) \u2013 Protection after Two Doses of Measles Vaccine Is Independent of Interval between Doses. In The Journal of Infectious Diseases, Volume 180, Issue 1, 1 July 1999, Pages 187\u2013190, <a href=\"https://doi.org/10.1086/314847\">https://doi.org/10.1086/314847</a> Online here: <a href=\"https://academic.oup.com/jid/article/180/1/187/990623\">https://academic.oup.com/jid/article/180/1/187/990623</a>.{/ref}</p>\n\n\n\n<p>The map here shows the coverage of the second dose (MCV2) of the measles vaccine. The current global average is 67%. The coverage is lowest in South Africa and many countries in Sub-Saharan Africa still have not introduced the vaccine into their immunization coverage.{ref}For guidelines on recommendations for the second dose of measles vaccine see here <a href=\"https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf\">https://www.who.int/immunization/sage/meetings/2016/october/Session6-MCV2-Introduction-criteria.pdf</a>{/ref} </p>\n\n\n\n<p><a href=\"https://ourworldindata.org/grapher/share-of-children-vaccinated-against-measles-vs-share-vaccinated-against-dpt3\">This scatterplot</a> compares the vaccination coverage against measles with the coverage against DTP3.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/share-of-children-vaccinated-with-mcv2\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h4>Global decline of measles</h4>\n\n\n\n<p>The second visualization shows the discussed increase of the global vaccination coverage of one-year-olds and the simultaneous decline of reported cases of the disease; from close to 1,000 cases per million people globally to 28 cases per million. This represents a 33-fold reduction.</p>\n\n\n\n<p>For country by country change over time see <a href=\"https://ourworldindata.org/grapher/reported-cases-of-measles\">this visualization</a>.</p>\n\n\n\n<figure><iframe loading=\"lazy\" style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/measles-vaccine-coverage-worldwide-vs-measles-cases-worldwide\" width=\"300\" height=\"150\"></iframe></figure>\n\n\n\n<h3>Rotavirus vaccines</h3>\n\n\n\n<p>The first widely-used rotavirus vaccine was approved in the United States in 2006. Today, there are four oral rotavirus vaccines recommended for use by the World Health Organisation (WHO): Rotarix, RotaTeq, RotaSiil, and Rotavac.{ref}World Health Organization. (2019). <em>Rotavirus</em>. [online] Available at: <a href=\"https://www.who.int/immunization/diseases/rotavirus/en/\">https://www.who.int/immunization/diseases/rotavirus/en/</a> [Accessed 14 Aug. 2019].{/ref}</p>\n\n\n\n<p> Rotarix and RotaTeq are the most widely used and both have shown good efficacy against rotavirus infections in clinical trials.{ref}Ruiz-Palacios, G. M., P\u00e9rez-Schael, I., Vel\u00e1zquez, F. R., Abate, H., Breuer, T., Clemens, S. C., \u2026 & Cervantes, Y. (2006). <a href=\"https://www.nejm.org/doi/full/10.1056/nejmoa052434\">Safety and efficacy of an attenuated vaccine against severe rotavirus gastroenteritis</a>. <em>New England Journal of Medicine</em>, <em>354</em>(1), 11-22.{/ref}{ref}Vesikari, T., Matson, D. O., Dennehy, P., Van Damme, P., Santosham, M., Rodriguez, Z., \u2026 & Shinefield, H. R. (2006). <a href=\"https://www.nejm.org/doi/full/10.1056/nejmoa052664\">Safety and efficacy of a pentavalent human\u2013bovine (WC3) reassortant rotavirus vaccine</a>. <em>New England Journal of Medicine</em>, <em>354</em>(1), 23-33.{/ref}</p>\n\n\n\n<p>Since the use of rotavirus vaccines have been approved, they have had a notable impact on the reduction of rotavirus-related deaths. According to a study published in 2018, the use of rotavirus vaccines prevented approximately 28,900 child deaths globally in 2016. However, as the chart shows, full vaccine use \u2013 that is a 100% coverage globally \u2013 could have prevented an additional 83,200 deaths.{ref}Troeger, C., Khalil, I. A., Rao, P. C., Cao, S., Blacker, B. F., Ahmed, T., \u2026 & Kang, G. (2018). <a href=\"https://jamanetwork.com/journals/jamapediatrics/fullarticle/2696431\">Rotavirus vaccination and the global burden of rotavirus diarrhea among children younger than 5 years</a>. <em>JAMA Pediatrics</em>, <em>172</em>(10), 958-965.{/ref} This means that, even at the current rates of efficacy, 53% of all deaths in children under-5 from rotavirus in 2016 could have been avoided by full vaccine coverage. </p>\n\n\n\n<p>In addition to saving lives, the rotavirus vaccine also reduces the burden on healthcare systems. Between 2008 and 2016 the introduction of the rotavirus vaccine has reduced the number of diarrhea-related hospital admissions on average by 40%.{ref}Aliabadi, Negar, et al. <a href=\"https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(19)30207-4/fulltext\">“Global impact of rotavirus vaccine introduction on rotavirus hospitalisations among children under 5 years of age, 2008\u201316: findings from the Global Rotavirus Surveillance Network.”</a> <em>The Lancet Global Health</em>7.7 (2019): e893-e903.{/ref}</p>\n\n\n\n<iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/avertable-deaths-from-rotavirus-with-full-vaccine-coverage\"></iframe>\n\n\n\n<h4>Rotavirus vaccine could save the lives of even more children</h4>\n\n\n\n<p>If there is so much scope for saving more children\u2019s lives, what is the reason that these children are still dying?</p>\n\n\n\n<p>There are two key barriers to achieving the full potential of the rotavirus vaccine: immunization rates, and the efficacy of the vaccine in specific regions.</p>\n\n\n\n<h4>Immunisation rates are still too low</h4>\n\n\n\n<p>According to the WHO, by the end of 2018, 101 countries were using the rotavirus vaccine. The major drivers for the introduction of the vaccine are the burden of diarrheal diseases, the availability of funding, and a favourable political climate for vaccines.{ref}</p>\n\n\n\n<p>The cost of rotavirus vaccines varies by country. For example, countries with a gross national income per capita of less than US$1,000 receive subsidies from the Global Alliance for Vaccines and Immunisation, and there the cost per dose is <a href=\"https://www.unicef.org/supply/files/Rotavaccine.pdf\">set between US$2.10 – 3.20</a>. With additional co-financing options can reduce the costs <a href=\"https://www.sabin.org/sites/sabin.org/files/frederic_debellut.pdf\">down to US$0.13</a>. In high-income countries, such as the US, the cost per dose is between <a href=\"https://www.cdc.gov/vaccines/programs/vfc/awardees/vaccine-management/price-list/index.html\">US$70 and 95</a></p>\n\n\n\n<p>Countries are more likely to introduce the vaccine if the political environment is favourably disposed towards them. For example, if a country has set a high priority on achieving the Millennium Development Goal targets or the introduction of vaccines is seen as a positive news story, especially during election years.</p>\n\n\n\n<p>Burchett, H. E. D., Mounier-Jack, S., Griffiths, U. K., Biellik, R., Ongolo-Zogo, P., Chavez, E., \u2026 & Molla, M. (2012). <a href=\"https://academic.oup.com/heapol/article/27/suppl_2/ii5/594662\">New vaccine adoption: qualitative study of national decision-making processes in seven low-and middle-income countries</a>. <em>Health policy and planning</em>, <em>27</em>(suppl_2), ii5-ii16.{/ref}</p>\n\n\n\n<p> The vaccine is only given to children \u2013 it\u2019s recommended that the vaccination should be initiated 15 weeks after birth and finished by the 32nd week. However, the global coverage is still very low: it is estimated that just 35% of under one-year-olds were vaccinated in 2018.{ref}World Health Organization (2019). <em>Immunization coverage</em>. [online] Available at: <a href=\"https://www.who.int/news-room/fact-sheets/detail/immunization-coverage\">https://www.who.int/news-room/fact-sheets/detail/immunization-coverage</a> [Accessed 14 Aug. 2019].{/ref}</p>\n\n\n\n<p>The map shows the WHO estimates on the share of one-year olds who received the full recommended dosage of the vaccine (two immunizations for Rotarix vaccine or three immunizations for RotaTeq vaccine). For many countries where data coverage is low, it\u2019s expected that the share of infants receiving the vaccine is very low. Some countries however did see rapid increases in rates of immunization. In a period of only a few years countries including <a href=\"https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine?tab=chart&time=2011..2018&country=SDN+GMB+MWI\">Sudan, Malawi and Gambia</a> have increased immunisation rates from below 10% to 80-95% \u2013 click on the country to see the change over time.</p>\n\n\n\n<iframe style=\"width: 100%; height: 600px; border: 0px none;\" src=\"https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-rotavirus-vaccine\"></iframe>\n\n\n\n<h4>Vaccine efficacy differs by region</h4>\n\n\n\n<p>Since most <a href=\"https://ourworldindata.org/grapher/child-deaths-from-rotavirus\">rotavirus cases</a> occur in Sub-Saharan Africa where <a href=\"https://ourworldindata.org/grapher/child-mortality-rate-from-rotavirus?tab=chart\">mortality from rotavirus infection is also the highest</a>, it is essential to increase and maintain high immunisation coverage in this region. However, in addition to delivering the vaccine for those who need it, we also need to work on improving its efficacy.</p>\n\n\n\n<p>Vaccine efficacy for the rotavirus vaccine is defined as the percentage reduction of the rate of diarrhea incidences in vaccinated versus unvaccinated groups of children. It is well established that the efficacy of the rotavirus vaccine is not the same across all countries \u2014 in countries with high child mortality rates the vaccine shows much lower efficacy.{ref}Clark, Andrew, et al. <a href=\"https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext\">“Efficacy of live oral rotavirus vaccines by duration of follow-up: a meta-regression of randomised controlled trials.”</a> <em>The Lancet Infectious Diseases</em> (2019).{/ref}</p>\n\n\n\n<p>The chart is from a recent study by Clark et <em>al.</em>, which looked at how the efficacy of live oral rotavirus vaccines changes in different countries following vaccination. The chart shows that in countries with high child mortality rates, not only is the immediate vaccine efficacy lower \u2013 98% in low child mortality countries versus 66% in high child mortality countries \u2013 but also the vaccine efficacy decreases faster in high child mortality countries over time.{ref}The <a href=\"https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(19)30126-4/fulltext\">Clark et al.</a> (2019) study defined low child mortality rate as less than 1.3% of newborns; medium mortality rate as between 1.35% and 2.81%; and high mortality rate as more than 2.81%{/ref}</p>\n\n\n\n<p> Five years after vaccination, the rotavirus vaccine reduces the chances of getting diarrhea by 90% in low child mortality countries and only by 30% in high mortality countries.</p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><a href=\"https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1.png\"><img loading=\"lazy\" width=\"748\" height=\"550\" src=\"https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1-748x550.png\" alt=\"\" class=\"wp-image-24252\" srcset=\"https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1-748x550.png 748w, https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1-150x110.png 150w, https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1-400x294.png 400w, https://owid.cloud/app/uploads/2019/08/Rotavirus-vaccine-efficacy-by-child-mortality-group-1-768x564.png 768w\" sizes=\"(max-width: 748px) 100vw, 748px\" /></a></figure></div>\n\n\n\n<p>The table shows how good the rotavirus vaccine is at preventing severe diarrhea and reducing hospitalization due to diarrhea in children under-5 in different regions.{ref}Lamberti, L. M., Ashraf, S., Walker, C. L. F., & Black, R. E. (2016). <a href=\"https://www.ingentaconnect.com/content/wk/inf/2016/00000035/00000009/art00016\">A systematic review of the effect of rotavirus vaccination on diarrhea outcomes among children younger than 5 years</a>. <em>The Pediatric Infectious Disease Journal</em>, <em>35</em>(9), 992-998.{/ref}</p>\n\n\n\n<p> In high-income countries, rotavirus vaccination has been shown to reduce the cases of severe rotavirus diarrhea by 91% and hospitalization by 94%. In Eastern Asia and Latin America, the effectiveness rates are lower but still high \u2013 preventing 88% and 80% of severe diarrhea cases, respectively. However, effectiveness in South Asia and Sub-Saharan Africa is significantly lower, only reducing severe diarrhea in around half of the cases.</p>\n\n\n\n<table id=\"tablepress-114\" class=\"tablepress tablepress-id-114\">\n<thead>\n<tr class=\"row-1 odd\">\n\t<th class=\"column-1\">Outcome </th><th class=\"column-2\">Region</th><th class=\"column-3\">Vaccine effectivness</th>\n</tr>\n</thead>\n<tbody class=\"row-hover\">\n<tr class=\"row-2 even\">\n\t<td rowspan=\"5\" class=\"column-1\">Severe rotavirus diarrhea</td><td class=\"column-2\">Developed</td><td class=\"column-3\">91%</td>\n</tr>\n<tr class=\"row-3 odd\">\n\t<td class=\"column-2\">Eastern Asia and Southeast Asia</td><td class=\"column-3\">88%</td>\n</tr>\n<tr class=\"row-4 even\">\n\t<td class=\"column-2\">Latin America and Caribbean</td><td class=\"column-3\">80%</td>\n</tr>\n<tr class=\"row-5 odd\">\n\t<td class=\"column-2\">Southern Asia</td><td class=\"column-3\">50%</td>\n</tr>\n<tr class=\"row-6 even\">\n\t<td class=\"column-2\">Sub-Saharan Africa</td><td class=\"column-3\">46%</td>\n</tr>\n<tr class=\"row-7 odd\">\n\t<td rowspan=\"4\" class=\"column-1\">Hospitalization due to rotavirus infection</td><td class=\"column-2\">Developed</td><td class=\"column-3\">94%</td>\n</tr>\n<tr class=\"row-8 even\">\n\t<td class=\"column-2\">Eastern Asia and Southeast Asia</td><td class=\"column-3\">94%</td>\n</tr>\n<tr class=\"row-9 odd\">\n\t<td class=\"column-2\">Latin America and Caribbean</td><td class=\"column-3\">84%</td>\n</tr>\n<tr class=\"row-10 even\">\n\t<td class=\"column-2\">Sub-Saharan Africa</td><td class=\"column-3\">58%</td>\n</tr>\n</tbody>\n</table>\n\n\n\n\n<p>The reasons for different responses to the vaccine are not entirely clear.{ref}Patel, M., Shane, A. L., Parashar, U. D., Jiang, B., Gentsch, J. R., & Glass, R. I. (2009). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3673012/#R3\">Oral rotavirus vaccines: how well will they work where they are needed most?</a>. <em>The Journal of Infectious Diseases</em>, <em>200</em>, S39-S48.{/ref} {ref}Parker, E. P., Ramani, S., Lopman, B. A., Church, J. A., Iturriza-Gomara, M., Prendergast, A. J., & Grassly, N. C. (2018). <a href=\"https://www.futuremedicine.com/doi/10.2217/fmb-2017-0128?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dwww.ncbi.nlm.nih.gov&\">Causes of impaired oral vaccine efficacy in developing countries</a>. <em>Future microbiology</em>, <em>13</em>(1), 97-118.{/ref}</p>\n\n\n\n<p> It is likely that the gut responses to the oral rotavirus vaccines in children in lower-income countries are different. This may be due to a variety of causes, including <a href=\"https://ourworldindata.org/micronutrient-deficiency\">micronutrient deficiencies</a>, pre-vaccination exposure to certain pathogens, and the presence of chronic conditions such as <a href=\"https://ourworldindata.org/malaria\">malaria</a> or <a href=\"https://ourworldindata.org/hiv-aids\">HIV</a>. Overall, the poor gut response to the live vaccine means the efficacy of the vaccine is reduced. Taking all of the above mentioned points into account, there are several interventions that could increase the benefits of the rotavirus vaccine even further. In addition to increasing the vaccine coverage, improving nutritional health (of both infants and mothers) and improving hygiene and sanitation conditions (to lower the prevalence of damaging pathogens) could have positive effects on the vaccine\u2019s efficacy.</p>\n\n\n\n<p>We are still at quite an early stage of the rotavirus vaccine use. Although the vaccine has brought huge benefits already, it could go even further. Improving vaccination coverage, particularly across Sub-Saharan Africa and South Asia is key to continued reduction of childhood deaths from diarrhea. Even at moderate levels of vaccine efficacy, a significant number of additional additional child deaths could be prevented every year. The bar chart above that shows the number of preventable deaths illustrates the potential for extended vaccine coverage to save many more lives. And this is already taking into account the regional differences in the vaccine\u2019s effectiveness.</p>\n\n\n\n<p>In addition to increased coverage, improving the effectiveness of the vaccine would go even further in tackling one of the leading causes of death.</p>\n\n\n\n<h3>Pneumococcal vaccines</h3>\n\n\n\n<p>There are a number of ways we could reduce the number of children dying from pneumonia, including eliminating the major risk factors such as <a href=\"https://ourworldindata.org/hunger-and-undernourishment\">undernutrition</a> and <a href=\"https://ourworldindata.org/indoor-air-pollution\">air pollution</a>, and providing better <a href=\"https://ourworldindata.org/grapher/pneumonia-careseeking\">access to treatment</a>.</p>\n\n\n\n<p>But we have another highly effective intervention: a <a href=\"https://ourworldindata.org/vaccination\">vaccine</a> against the major pathogen responsible for pneumonia in children. </p>\n\n\n\n<p><em>Streptococcus pneumoniae </em>is the leading cause of pneumonia in children under 5 \u2014 it was responsible for 52% of all fatal pneumonia cases in children in 2016.{ref}Troeger, C., Blacker, B., Khalil, I. A., Rao, P. C., Cao, J., Zimsen, S. R., … & Adetifa, I. M. O. (2018). <a href=\"https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(18)30310-4/fulltext\">Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory infections in 195 countries, 1990\u20132016: a systematic analysis for the Global Burden of Disease Study 2016.</a><em> The Lancet Infectious Diseases</em>, <em>18</em>(11), 1191-1210.{/ref} Pneumococcal vaccines are vaccines that target <em>S. pneumoniae</em> bacteria. Here we look at their effectiveness and how we can maximise the number of children they save.</p>\n\n\n\n<h4>The coverage of pneumococcal vaccines is still low</h4>\n\n\n\n<p>Since the World Health Organisation (WHO) started recommending including pneumococcal vaccines in national immunisation programmes for children in 2007, there has been a progressive increase in the number of countries using the vaccine. You can see the uptake in the vaccine across the world using the \u2018play\u2019 button on the map below. </p>\n\n\n\n<p>But the coverage of pneumococcal vaccines is still low in many countries. In India and Nigeria \u2013 the two countries with the <a href=\"https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5\">greatest number</a> of childhood deaths from pneumonia in 2019 \u2013 only 44% and 58% of one-year-olds are vaccinated, respectively.\u00a0 </p>\n\n\n\n<p>In 2018, less than half (47%) of one-year-olds in the world received the full course of pneumococcal vaccination. This means that 55 million children who could be protected by the vaccine are still not vaccinated against it \u2014 an appallingly high number for a vaccine that not only protects from pneumonia, the leading cause of childhood death, but also a range of other diseases (as discussed below).{ref}Who.int. (2019) \u2013 <a href=\"https://www.who.int/news-room/fact-sheets/detail/immunization-coverage\"><em>Immunization coverage</em></a>. [online] [Accessed 10 Sep. 2019]. <a href=\"http://view-hub.org/viz/\">http://view-hub.org/viz/</a> (Go to PCV \u2014> PCV – Vaccine Access \u2014> Children without Access){/ref}</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h4>How do pneumococcal vaccines work?</h4>\n\n\n\n<p><em>Streptococcus pneumonia</em>, often simply referred to as pneumococcus, is a bacterium that is often found in the upper respiratory tract of healthy people. Generally, the bacterium is harmless or causes milder illnesses such as bronchitis, sinusitis, and ear infections. Pneumococcal vaccines are effective against these milder illnesses as well, but importantly also protects from what is called pneumococcal invasive disease (PID). PID occurs when the pneumococcus moves from colonizing the upper respiratory tract to colonizing sites that are normally sterile, such as blood, cerebrospinal fluid or pleural cavity (fluid-filled space surrounding the lungs).{ref}Hanada, S., Pirzadeh, M., Carver, K. Y., & Deng, J. C. (2018). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6250824/\">Respiratory Viral Infection-Induced Microbiome Alterations and Secondary Bacterial Pneumonia.</a> <em>Frontiers in immunology</em>, <em>9</em>, 2640.{/ref} Bacterial invasion leads to life-threatening diseases such as sepsis, meningitis and severe pneumonia. </p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/child-deaths-from-streptococcus-by-disease\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<p>There are two types of pneumococcal vaccines available: conjugated polysaccharide pneumococcal vaccine (PCV) and non-conjugated polysaccharide pneumococcal vaccine (PPSV). Both vaccines are designed to elicit immune responses against multiple serotypes of pneumococcus, which are defined by the different immune responses to the sugars found on the bacterial surface.{ref}Song, J. Y., Nahm, M. H., & Moseley, M. A. (2013). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3546102/\">Clinical implications of pneumococcal serotypes: invasive disease potential, clinical presentations, and antibiotic resistance</a>. <em>Journal of Korean medical science</em>, <em>28</em>(1), 4-15.{/ref} To be broadly effective, the vaccines need to protect against a certain number of these pneumococcal serotypes, but it is not necessary to include all possible serotypes because only a limited subset is responsible for 70%-80% of invasive pneumococcal disease.{ref}The number of serotypes included in the vaccine is generally indicated in its name, e.g. PCV13 is pneumococcal conjugate vaccine effective against 13 bacterial serotypes. Vaccines including progressively more serotypes have been introduced over the years, PCV7 was introduced in 2000 and today the most commonly used PCV13 was introduced in 2010.</p>\n\n\n\n<p>Hausdorff, W. P., Feikin, D. R., & Klugman, K. P. (2005). <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/15680778/\">Epidemiological differences among pneumococcal serotypes.</a> <em>The Lancet infectious diseases</em>, <em>5</em>(2), 83-93.{/ref} However, as we\u2019ll discuss later, this variety of different pneumococcal serotypes is important to keep in mind because as vaccine coverage increases we may see a replacement of the vaccine-included serotypes with the less dominant ones, which will mean new vaccine versions will be required. <br></p>\n\n\n\n<p>While there are two types of pneumococcal vaccines available, for children under two years old only the conjugated (i.e. PCV) vaccines are recommended because the non-conjugated versions (i.e. PPSV) are not effective at such a young age.{ref}The current non-conjugate vaccine, PPSV23, is generally only given to adults or as a single dose following two immunisations with PCV13 in children older than 2.</p>\n\n\n\n<p>Golos, M., Eliakim\u2010Raz, N., Stern, A., Leibovici, L., & Paul, M. (2016). <a href=\"https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD012306/full\">Conjugated pneumococcal vaccine versus polysaccharide pneumococcal vaccine for prevention of pneumonia and invasive pneumococcal disease in immunocompetent and immunocompromised adults and children.</a> <em>Cochrane Database of Systematic Reviews</em>, (8).{/ref} </p>\n\n\n\n<h4>How effective are pneumococcal vaccines?</h4>\n\n\n\n<p>In clinical trials PCV has shown 80% efficacy in reducing invasive pneumococcal disease caused by the bacterial serotypes included in the vaccine formulation. Vaccinated children are 27% less likely to be diagnosed with pneumonia and 11% less likely to die from it.{ref}The 27% refers to X-ray-defined cases of pneumonia. For clinically defined pneumonia, a less accurate diagnosis than X-ray-defined cases, the number is 6%. Both of these indicators refer to cases of pneumonia caused by any pathogen not only pneumococcus. Lucero, M. G., Dulalia, V. E., Nillos, L. T., Williams, G., Parre\u00f1o, R. A. N., Nohynek, H., … & Makela, H. (2009). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6464899/\">Pneumococcal conjugate vaccines for preventing vaccine\u2010type invasive pneumococcal disease and X\u2010ray defined pneumonia in children less than two years of age</a>. <em>Cochrane Database of Systematic Reviews</em>, (4).{/ref} </p>\n\n\n\n<p>Several studies have attempted to estimate how many lives PCV vaccination has saved and could possibly save. One <em>Lancet </em>study concluded that between 2000 and 2015, in 120 countries the number of childhood deaths caused by pneumococcus fell from 600,000 to 294,000 \u2014 a decline of 54%. Most of this decline was attributed to the PCV vaccines: over this period, it\u2019s estimated these vaccines saved the lives of 250,000 children. The majority of these deaths would have been caused by pneumonia, but the vaccine also prevented deaths from pneumococcal meningitis and other diseases.{ref}Wahl, B., O’Brien, K. L., Greenbaum, A., Majumder, A., Liu, L., Chu, Y., … & Rudan, I. (2018). <a href=\"https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30247-X/fulltext\">Burden of Streptococcus pneumoniae and Haemophilus influenzae type b disease in children in the era of conjugate vaccines: global, regional, and national estimates for 2000\u201315.</a><em> The Lancet Global Health</em>, <em>6</em>(7), e744-e757.{/ref} </p>\n\n\n\n<h4>How many child deaths could be averted by pneumococcal vaccines?</h4>\n\n\n\n<p>The chart shows how estimates of the potential impact of the pneumococcal vaccine.</p>\n\n\n\n<p>It is based on a recent study published in <em>The Lancet Global Health</em> journal, which calculated that if the PCV vaccine coverage would reach at least the levels of the <a href=\"https://ourworldindata.org/grapher/share-of-children-immunized-dtp3\">vaccination against diphtheria, tetanus and pertussis</a> (DTP3), the lives of 399,000 children under 5 could be saved.{ref}Chen, C., Liceras, F. C., Flasche, S., Sidharta, S., Yoong, J., Sundaram, N., & Jit, M. (2019). <a href=\"https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30422-4/fulltext\">Effect and cost-effectiveness of pneumococcal conjugate vaccination: a global modelling analysis.</a><em> The Lancet Global Health</em>, <em>7</em>(1), e58-e67.{/ref} Additionally the researchers estimate that 54.6 million pneumonia episodes annually could be averted.</p>\n\n\n\n<p>These number estimate the impact of the PCV vaccination relative to a world without that vaccine \u2013 since the vaccine is already used it means that some of these lives are already being saved by the PVC vaccination. However, in many countries <a href=\"https://ourworldindata.org/grapher/diphtheria-tetanus-pertussis-vaccine-vs-pneumococcal-vaccine-coverage\">PCV vaccination rates still fall far below the DTP3 rates</a>, making clear that we still haven\u2019t used the pneumococcal vaccine to its full potential.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/pneumococcal-vaccination-averted-deaths\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h4>What can we do to improve the coverage and effectiveness of pneumococcal vaccines?</h4>\n\n\n\n<p>A continued increase in immunization coverage and the introduction of PCV vaccines into countries which don\u2019t yet use them is important if we want to make use of the full potential of pneumococcal vaccines. </p>\n\n\n\n<p>PCV vaccines are amongst the most expensive vaccines in national immunisation programmes. The price ranges from $3.05 per dose in GAVI{ref} GAVI (Global Alliance for Vaccines and Immunisation) is a non-profit organisation that provides access to vaccination programs for low-income countries by providing financial support and individual expertise.{/ref} supported low-income countries to $169 in high-income countries such as the United States.{ref}O’Brien, K. L. (2018). <a href=\"https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc\">When less is more: how many doses of PCV are enough?.</a><em> The Lancet Infectious Diseases</em>, <em>18</em>(2), 127-128.{/ref} For low-middle-income countries who are transitioning from GAVI support the increasing future costs of vaccination place a considerable strain on national healthcare budgets.{ref}For example Kenya has recently entered a transition phase during which it will pay a larger and larger portion of the PCV vaccine cost. By 2027 Kenya will have to pay the full $9 price for a three-dose course child vaccination. The 2016 <a href=\"https://databank.worldbank.org/Kenya-healthcare-per-capita-/id/58f0a890\">per capita healthcare expenditure in Kenya</a> was around $66 (5% of the GDP), clearly $9 per child is not a trivial cost.</p>\n\n\n\n<p>Simonsen, L., van Wijhe, M., & Taylor, R. (2019). <a href=\"https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext\">Are expensive vaccines the best investment in low-income and middle-income countries?</a>. <em>The Lancet Global Health</em>, <em>7</em>(5), e548-e549.</p>\n\n\n\n<p>Ojal, J., Griffiths, U., Hammitt, L. L., Adetifa, I., Akech, D., Tabu, C., … & Flasche, S. (2019). <a href=\"https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30562-X/fulltext\">Sustaining pneumococcal vaccination after transitioning from Gavi support: a modelling and cost-effectiveness study in Kenya.</a><em> The Lancet Global Health</em>, <em>7</em>(5), e644-e654.{/ref} </p>\n\n\n\n<p>But given the high burden of pneumococcal diseases, even at high prices, PCV vaccines are considered to be cost-effective, with an estimated return of investment in low- and middle-income countries of around 3.{ref}The return of investment was estimated for a projected coverage for individual countries for the decade between 2011 and 2020. It means that the economic benefits (as measured by the costs of vaccination program subtracted from the reduced costs of treatment and productivity loss) of using the vaccine are 3 times higher than no vaccine use. <br>To reduce costs, some countries may also consider switching to a two rather than three dose immunization schedule, but more research on the effectiveness of this schedule in different countries is needed. See O’Brien et al. (2018) reference.</p>\n\n\n\n<p>Nakamura, M. M., Tasslimi, A., Lieu, T. A., Levine, O., Knoll, M. D., Russell, L. B., & Sinha, A. (2011). <a href=\"https://academic.oup.com/inthealth/article-lookup/doi/10.1016/j.inhe.2011.08.004\">Cost effectiveness of child pneumococcal conjugate vaccination in middle-income countries.</a> <em>International health</em>, <em>3</em>(4), 270-281.<br></p>\n\n\n\n<p>Ozawa, S., Clark, S., Portnoy, A., Grewal, S., Brenzel, L., & Walker, D. G. (2016). <a href=\"https://www.healthaffairs.org/doi/full/10.1377/hlthaff.2015.1086?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed\">Return on investment from childhood immunization in low-and middle-income countries, 2011\u201320.</a> <em>Health Affairs</em>, <em>35</em>(2), 199-207.<br></p>\n\n\n\n<p>Center, I. V. A. (2017). <a href=\"https://www.jhsph.edu/ivac/wp-content/uploads/2018/05/PCVEvidenceBase-Jan2017.pdf\">The evidence base for pneumococcal conjugate vaccines (PCVs): data for decision-making around PCV use in childhood.</a> <em>Baltimore (MD): Johns Hopkins University</em>.<br></p>\n\n\n\n<p>Goldblatt, D., Southern, J., Andrews, N. J., Burbidge, P., Partington, J., Roalfe, L., … & Snape, M. D. (2018). <a href=\"https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30654-0/fulltext\">Pneumococcal conjugate vaccine 13 delivered as one primary and one booster dose (1+ 1) compared with two primary doses and a booster (2+ 1) in UK infants: a multicentre, parallel group randomised controlled trial.</a> <em>The Lancet Infectious Diseases</em>, <em>18</em>(2), 171-179.</p>\n\n\n\n<p>O’Brien, K. L. (2018). <a href=\"https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(17)30684-9/fulltext?elsca1=etoc\">When less is more: how many doses of PCV are enough?.</a><em> </em><em>The Lancet Infectious Diseases</em>, <em>18</em>(2), 127-128.{/ref} </p>\n\n\n\n<p>PCV vaccines include a limited subset of possible pneumococcal serotypes. The distribution of pneumococcal serotypes is known to vary between countries and PCV vaccines include the ones that are most common globally. </p>\n\n\n\n<p>Which non-vaccine serotypes are most common in a particular country, may affect the potential for a particular vaccine\u2019s impact. However, not all countries collect data on serotype distribution, and an assessment of the potential impact is therefore compromised.{ref}Adegbola, R. A., DeAntonio, R., Hill, P. C., Roca, A., Usuf, E., Hoet, B., & Greenwood, B. M. (2014). <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/25084351\">Carriage of Streptococcus pneumoniae and other respiratory bacterial pathogens in low and lower-middle income countries: a systematic review and meta-analysis</a>. <em>PloS one</em>, <em>9</em>(8), e103293.{/ref} {ref}Megiddo, I., Klein, E., & Laxminarayan, R. (2018). <a href=\"https://gh.bmj.com/content/3/3/e000636\">Potential impact of introducing the pneumococcal conjugate vaccine into national immunisation programmes: an economic-epidemiological analysis using data from India.</a><em> BMJ global health</em>, <em>3</em>(3), e000636.{/ref} {ref}Johnson, H. L., Deloria-Knoll, M., Levine, O. S., Stoszek, S. K., Hance, L. F., Reithinger, R., … & O’Brien, K. L. (2010). <a href=\"https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1000348\">Systematic evaluation of serotypes causing invasive pneumococcal disease among children under five: the pneumococcal global serotype project.</a><em>PLoS medicine</em>, <em>7</em>(10), e1000348.{/ref} Notably, since the PCV vaccine was introduced, there has been a rise in pneumococcal invasive disease incidences caused by the less common serotypes. This suggests that, by reducing the prevalence of vaccine-included serotypes, the vaccine unintentionally provides space for non-vaccine serotypes, against which it works less well.{ref}World Health Organization. (2010). <a href=\"https://www.who.int/wer/2010/wer8543.pdf?ua=1\">Changing epidemiology of pneumococcal serotypes after introduction of conjugate vaccine: July 2010 report.</a><em> Weekly Epidemiological Record [Relev\u00e9 \u00e9pid\u00e9miologique hebdomadaire</em>], <em>85</em>(43), 434-436.{/ref} This means that the vaccine’s effectiveness may decrease over time, if the serotype formulation of PCV is not continually reevaluated. In the future, new versions of pneumococcal vaccines may be needed that work better independently of the bacterial serotype. Such vaccines are already in development.{ref}Pichichero, M. E. (2017). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277969/\">Pneumococcal whole-cell and protein-based vaccines: changing the paradigm</a>. <em>Expert review of vaccines</em>, <em>16</em>(12), 1181-1190.{/ref} {ref}Ginsburg, A. S., Nahm, M. H., Khambaty, F. M., & Alderson, M. R. (2012). Issues and challenges in the development of pneumococcal protein vaccines. Expert review of vaccines, 11(3), 279-285{/ref} <br></p>\n\n\n\n<h3>Hepatitis B vaccine</h3>\n\n\n\n<p>The chart here shows the coverage for Hepatitis B vaccination.</p>\n\n\n\n<p>Hepatitis B (HepB) is a highly contagious viral infection that attacks the liver and is transmitted through contact with the blood or other body fluids of an infected person. As the chart shows, it is estimated that about 100,000 people die each year of chronic liver disease due to hepatitis B. The WHO recommends that all infants should receive their first dose of vaccine as soon as possible after birth, preferably within 24 hours.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/immunization-hepb3-of-one-year-old-children\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>Haemophilus influenzae type b vaccine</h3>\n\n\n\n<p>Haemophilus influenzae type b (Hib) is a bacterial infection that causes meningitis and pneumonia transmitted through the respiratory tract from infected to susceptible individuals. The chart here shows the coverage for Hib vaccination.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/hib-vaccine\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>Polio vaccine</h3>\n\n\n\n<p>The chart here shows the coverage of the polio vaccine.</p>\n\n\n\n<p>Poliomyelitis (OPV, IPV) is a highly infectious viral disease. Once the poliovirus invades the nervous system it can cause irreversible paralysis in a matter of hours. No cure exists for polio, only treatment to alleviate symptoms. As we detail in our <a href=\"https://owid.cloud/polio\">entry on polio</a> the world is on its way to eradicate the disease thanks to the vaccine against the virus: While in the 1980s there were 350,000 paralytic cases of polio every year, the world saw only 42 cases in 2016. </p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/polio-vaccine-coverage-of-one-year-olds\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>Tuberculosis vaccine (BCG)</h3>\n\n\n\n<p>The chart here shows the coverage of the BCG vaccine, which protects against tuberculosis.</p>\n\n\n\n<p>Developed more than a century ago, bacille Calmette\u2013Gu\u00e9rin vaccine (BCG) is currently the only vaccine available against tuberculosis (TB). </p>\n\n\n\n<p>Close to 4 billion people have been vaccinated with BCG – this makes it the most widely used vaccine in the world.{ref}Kendig, E. L., Wilmott, R. W., & Chernick, V. (2012). <a href=\"https://www.sciencedirect.com/science/article/pii/B9780323448871000298\"><em>Kendig and Chernick’s disorders of the respiratory tract in children</em></a>. 9th ed. Elsevier Health Sciences.{/ref} </p>\n\n\n\n<p>BCG vaccine is based on a reduced-virulence strain of <em>Mycobacterium bovis</em>, a bacterium that is closely related to <em>Mycobacterium tuberculosis</em> – the pathogen that causes TB. BCG vaccine was already used in the 1920s in Belgium and France in small trials and after the Second World War its use was expanded to vaccinate children across Europe. In 1950s the WHO started recommending the use of BCG globally. <br></p>\n\n\n\n<p>BCG is effective at protecting children and adolescents from severe forms of TB and meningitis.{ref}\u00a0Rodrigues, L. C., Mangtani, P., & Abubakar, I. (2011).<a href=\"https://www.bmj.com/content/343/bmj.d5974.full\"> How does the level of BCG vaccine protection against tuberculosis fall over time?</a>. <em>Bmj</em>, <em>343</em>, d5974.{/ref} {ref}Rodrigues, L. C., Diwan, V. K., & Wheeler, J. G. (1993). <a href=\"https://academic.oup.com/ije/article-abstract/22/6/1154/650235\">Protective effect of BCG against tuberculous meningitis and miliary tuberculosis: a meta-analysis.</a><em>International journal of epidemiology</em>, <em>22</em>(6), 1154-1158.{/ref} However, studies have shown that the length of protection provided by the vaccine varies greatly depending on the populations studied: from 15 years in the UK to 50\u201360 years in Alaska.{ref}Sterne, J. A. C., Rodrigues, L. C., & Guedes, I. N. (1998).<a href=\"https://www.ingentaconnect.com/content/iuatld/ijtld/1998/00000002/00000003/art00005\"> Does the efficacy of BCG decline with time since vaccination?.</a><em>The international journal of tuberculosis and lung disease</em>, <em>2</em>(3), 200-207.{/ref} {ref}Aronson, N. E., Santosham, M., Comstock, G. W., Howard, R. S., Moulton, L. H., Rhoades, E. R., & Harrison, L. H. (2004). <a href=\"https://jamanetwork.com/journals/jama/article-abstract/198681\">Long-term efficacy of BCG vaccine in American Indians and Alaska Natives: a 60-year follow-up study.</a><em>Jama</em>, <em>291</em>(17), 2086-2091.{/ref} The reason for such variability is not clear, but factors such as different vaccine seed strains used for immunization and pre-existing immunity in people already exposed to other mycobacteria strains may be important.\u00a0<br>Notably, BCG vaccine does not protect people from primary infections, that is it does not prevent people from getting infected with <em>M. tuberculosis </em>bacterium in the first place. BCG also does not prevent activation of latent TB if a person has already been infected. Therefore, the vaccine has limited effect on prevention of <em>M. tuberculosis </em>spread in a population.{ref} https://www.who.int/biologicals/areas/vaccines/bcg/en/ {/ref}</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/bcg-immunization-coverage-for-tb-among-1-year-olds\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>Yellow fever vaccine</h3>\n\n\n\n<p>The chart here shows the coverage of the yellow fever vaccine.</p>\n\n\n\n<p>Yellow fever (YF) is a viral disease transmitted by infected mosquitoes. There are 40 countries and territories at risk for yellow fever in Africa and the Americas and of these 36 include yellow fever vaccination in their routine immunization schedules. Total, vaccine coverage in 2018 was estimated at 49%.{ref}<a href=\"https://www.who.int/news-room/fact-sheets/detail/immunization-coverage\">https://www.who.int/news-room/fact-sheets/detail/immunization-coverage</a>{/ref}</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/yellow-fever-vaccine-coverage\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h2>Definitions and Measurement</h2>\n\n\n\n<h4>Calculating coverage</h4>\n\n\n\n<p>The coverage is calculated as the proportion of persons in a target age group who received a vaccine dose. Dates of vaccination are either taken from a child\u2019s home-based record, recorded based on caregiver recall, or from health facility records.</p>\n\n\n\n<p>While appearing straightforward enough, several methodological problems of household survey respondent data on vaccination have been well documented.{ref}Daniel A. Salmon, Philip J. Smith, Ann Marie Navar, William K. Y. Pan, Saad B. Omer, James A. Singleton, Neal A. Halsey; Measuring Immunization Coverage among Preschool Children: Past, Present, and Future Opportunities, <em>Epidemiologic Reviews</em>, Volume 28, Issue 1, 1 August 2006, Pages 27\u201340, <a href=\"https://doi.org/10.1093/epirev/mxj001\">https://doi.org/10.1093/epirev/mxj001</a>{/ref}</p>\n\n\n\n<p>Questions have arisen about how accurately parents can recall child immunization history and the limitations of phone calls to collect data.</p>\n\n\n\n<p>Even accurately estimating target populations in low-income settings can be difficult and discrepancies have been found when comparing country-reported figures with independent surveys.{ref}”Global childhood immunization coverage growing at only half the officially reported rate, IHME study” online here: <a href=\"http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme\">http://www.healthdata.org/news-release/global-childhood-immunization-coverage-growing-only-half-officially-reported-rate-ihme</a>{/ref}</p>\n\n\n\n<p>Furthermore, childhood vaccinations are rarely considered altogether. The DTP3 vaccination tends to be the vaccination most often used as a marker of strength in a country\u2019s immunization programs, since three administrations of the vaccination are required.{ref}Other vaccines measured by the WHO and UNICEF are HepB3, Hib3, MCV and PAB.{/ref}</p>\n\n\n\n<h4>National and subnational coverage</h4>\n\n\n\n<p>National coverage rates are what is focused upon, but even when national coverage are high, subnational coverage can reveal inequities, which is why the WHO and UNICEF are increasing efforts to gather high quality subnational coverage data.{ref}See: <a href=\"http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/\">http://www.who.int/immunization/newsroom/press/immunization_coverage_july_2016/en/</a>{/ref}</p>\n\n\n\n<p>In 2015 coverage estimates at the district level were only reported for 158 of the 194 WHO Member States. National data only provides part of the picture of immunization coverage. Different levels of coverage data, including at sub-national or district level is useful for gaining an understanding of where there might be clusters of under- or un-vaccinated children.</p>\n\n\n\n<h2>Data Sources</h2>\n\n\n\n<h4>World Health Organization – Immunization surveillance, assessment and monitoring</h4>\n\n\n\n<ul><li><strong>Data:</strong> Immunization coverage, system indicators and schedule, and disease incidence</li><li><strong>Geographical coverage:</strong> WHO member nations</li><li><strong>Time span:</strong> 1980 onwards for many countries</li><li><strong>Available at:</strong> Online <a href=\"http://www.who.int/immunization/monitoring_surveillance/data/en/\">here</a></li></ul>\n\n\n\n<h4>UNICEF</h4>\n\n\n\n<ul><li><strong>Data:</strong> Percent of one-year-olds immunized</li><li><strong>Geographical coverage:</strong> UN member nations</li><li><strong>Time span:</strong> 1980 onwards for many countries</li><li><strong>Available at:</strong> Online from UNICEF <a href=\"http://web.archive.org/web/20150709064229/http://data.unicef.org/child-health/immunization\">here</a>. Also available via Gapminder <a href=\"http://www.gapminder.org/data/\">here</a> (search “vaccine” to find the data).</li></ul>\n\n\n\n<h4>Further reading</h4>\n\n\n\n<p>More information about vaccines in general can be found on the World Health Organization (WHO) page on <a href=\"http://www.who.int/topics/immunization/en/\">immunization</a>.</p>\n", "protected": false }, "excerpt": { "rendered": "Vaccines are key in making progress against infectious diseases and save millions of lives every year.", "protected": false }, "date_gmt": "2013-05-10T23:14:52", "modified": "2022-10-13T11:56:30", "template": "", "categories": [ 44, 46, 172 ], "menu_order": 350, "ping_status": "closed", "authors_name": [ "Samantha Vanderslott", "Saloni Dattani", "Fiona Spooner" ], "modified_gmt": "2022-10-13T10:56:30", "comment_status": "open", "featured_media": 38637, "featured_media_paths": { "thumbnail": "/app/uploads/2020/12/Screen-Shot-2020-12-30-at-19.13.37-150x91.png", "medium_large": "/app/uploads/2020/12/Screen-Shot-2020-12-30-at-19.13.37-768x465.png" } } |