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26939 | Pneumonia | pneumonia | page | publish | <!-- wp:html --> <div class="blog-info">This entry was first published in November 2019.</div> <!-- /wp:html --> <!-- wp:paragraph --> <p>2.5 million people died from pneumonia in 2019. Almost a third of all victims were children younger than 5 years, it is the leading cause of death for children under 5.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Pneumonia is an infection of the tiny air sacs of the lungs, called alveoli. In a person with pneumonia the alveoli are filled with pus and fluid, which makes breathing painful and reduces the oxygen intake. Pneumonia is caused by a number of different infectious agents, including viruses, bacteria and fungi.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Here in this research entry we look at who is suffering from pneumonia and why – and what can we do to reduce the number of people dying from this disease. </p> <!-- /wp:paragraph --> <!-- wp:owid/summary {"className":"wp-block-owid-summary"} --> <!-- wp:list --> <ul><li><a href="#burden-of-pneumonia">Pneumonia is the leading cause of death for children under 5 — more than 800,000 children died due to pneumonia in 2017.</a></li><li><a href="#burden-of-pneumonia">While still too many children die today, since 1990 we’ve seen more than 3-fold reduction in child mortality rates from pneumonia globally.</a></li><li><a href="#pneumonia-mortality-rates-by-age">The global mortality rates for older people remained unchanged since 1990.</a></li><li><a href="#where-do-children-die-from-pneumonia">Mortality from pneumonia is highest in Sub-Saharan Africa.</a></li><li><a href="#what-are-the-biggest-risks-for-developing-pneumonia">The greatest risk factors for developing pneumonia are undernutrition, air pollution and smoking.</a></li><li><a href="#how-can-we-reduce-the-number-of-people-dying-from-pneumonia">Reducing exposure to risk factors and higher coverage of pneumococcal vaccines can reduce the number deaths from pneumonia.</a></li><li><a href="#pneumococcal-vaccines">Research suggests that pneumococcal vaccines could be saving the lives of almost 400,000 children annually.</a></li></ul> <!-- /wp:list --> <!-- /wp:owid/summary --> <!-- wp:paragraph --> <p> </p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Estimates that refer to pneumonia might also include cases of other lower respiratory diseases</h4> <!-- /wp:heading --> <!-- wp-block-tombstone 27069 --> <!-- wp:paragraph --> <p>Ideally, pneumonia would always be diagnosed by a physician using radiological imaging and determining the infectious agent that caused the disease. However, because such diagnosis requires a lot of resources, it is in many cases not done.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>This is why research literature uses the terms 'clinical pneumonia' or 'WHO-pneumonia' to diagnoses based on <em>symptoms</em> (most importantly, fast breathing and coughing). A symptoms-based definition inevitably means that diseases with similar symptoms may be counted as cases of pneumonia.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>As a consequence the terms pneumonia and lower respiratory infections (LRIs) are often used interchangeably. The <em>Institute for Health Metrics and Evaluation </em>(IHME), for example, provides mortality data on LRIs, in which they include pneumonia caused by a range of different pathogens, but they also include bronchiolitis, a lower respiratory tract infection that mostly affects very young children, in this category.{ref}Institute for Health Metrics and Evaluation (IMHE). (2014). <a href="http://www.healthdata.org/sites/default/files/files/policy_report/2014/PolicyReport_IHME_PushingthePace_2014.pdf">Pushing the Pace: Progress and Challenges in Fighting Childhood Pneumonia.</a>{/ref} {ref}McAllister, D. A., Liu, L., Shi, T., Chu, Y., Reed, C., Burrows, J., ... & Nair, H. (2019). <a href="https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf">Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic analysis.</a> <em>The Lancet Global Health</em>, <em>7</em>(1), e47-e57.{/ref} While cases of bronchiolitis are quite common they are generally not fatal, therefore, it is reasonable to assume that the bulk of IHME estimates for the number of deaths from lower respiratory diseases do refer to deaths from pneumonia. </p> <!-- /wp:paragraph --> <!-- wp:heading --> <h2>Burden of pneumonia</h2> <!-- /wp:heading --> <!-- wp:heading {"level":3} --> <h3>Number of people dying from pneumonia by age</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 27071 --> <!-- wp:paragraph --> <p>In the visualization here we see the global number of deaths from pneumonia{ref}We use the term pneumonia here as a broad term for lower respiratory infections, see <a href="#estimates-that-refer-to-pneumonia-might-also-include-cases-of-other-lower-respiratory-diseases">this section</a> for how these terms are defined and why they are grouped together.{/ref} by age group.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>15% of all <a href="https://owid.cloud/child-mortality">child deaths</a> in 2017 were caused by pneumonia and it is therefore the leading cause of death of children (see our discussion <a href="https://ourworldindata.org/child-mortality#what-are-children-dying-from">here</a>).</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The number of children dying from pneumonia has decreased substantially over the past three decades. In 1990, more than two million children died from pneumonia every year. By 2017, this number had fallen by almost two-thirds. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Improvements in the major risk factors such as <a href="https://ourworldindata.org/hunger-and-undernourishment#too-little-weight-for-height-wasting">childhood wasting</a>, <a href="https://ourworldindata.org/air-pollution">air pollution</a>, and <a href="https://ourworldindata.org/grapher/death-rate-from-unsafe-sanitation">poor sanitation</a>, falling <a href="https://owid.cloud/extreme-poverty">global poverty</a>, and a better availability of health technology such as pneumococcal vaccines and antibiotics have all contributed to this decline.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>While the death <em>rate</em> for old people fell slightly, the <em>number</em> of deaths of people who are 70 years and older increased. <a href="https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths">1.13 million</a>, who died from pneumonia where in this age group. This is because the number of people who reached the age of 70 increased very strongly globally as we show in <a href="https://owid.cloud/age-structure">our entry</a> on the changing global age structure. </p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Pneumonia mortality rates by age</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 27073 --> <!-- wp:paragraph --> <p>The chart shows the annual number of deaths from pneumonia per 100,000 people in different age groups.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Looking at the age-group of under 5 year olds we see that there has been a 3-fold reduction in child mortality due to pneumonia over the last three decades. 363 children out of every 100,000 died due to pneumonia in 1990, until 2017 that number has fallen to 119.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The mortality rates among other age groups have remained largely the same. The highest pneumonia mortality rates in 2017 were among people aged 70 and older. 261 out of 100,000 people died in this age group due to pneumonia. That's a 9% decrease in mortality rates over the past 3 decades.{ref}(286.1-260.9)/286.1=0.09{/ref} </p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/pneumonia-mortality-by-age" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading --> <h2>Where do people die from pneumonia?</h2> <!-- /wp:heading --> <!-- wp:heading {"level":3} --> <h3>Pneumonia death rates – all ages</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>In the map we see the death rate from pneumonia expressed as the number of deaths due to pneumonia per year per 100,000 individuals. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>We can see that the death rate from pneumonia is highest in Sub-Saharan Africa and Southeast-Asia. The difference between richer and poorer countries is large: European populations suffer a rate of around 10 deaths per 100,000 while poorer countries see rate of more than 100 deaths per 100,000 is </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In Southeast-Asia, the population of the Philippines suffer from particularly high pneumonia mortality rates; pneumonia is the second leading cause of death in both under-5-year-old and <a href="https://ourworldindata.org/grapher/pneumonia-death-rates-70">older than 70</a>-year-old populations in this country. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>These rates have been age-standardized, which tells us the death rate for each country and each point in time as if the age structure of a population. This therefore allows us to make across comparisons across countries and through time that are not affected by differences in the age-structure between countries and changes of the age-structure over time.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/pneumonia-death-rates-70" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":3} --> <h3>Where do children die from pneumonia</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 27058 --> <!-- wp:paragraph --> <p>The map shows the number of child deaths due to pneumonia per 100,000 children per year.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>It shows that children are most likely to die from pneumonia across Sub-Saharan Africa and South Asia. The deaths in just <a href="https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5">5 countries</a> — India, Nigeria, Pakistan, the Democratic Republic of Congo, and Ethiopia – accounted for more than half of all deaths from childhood pneumonia in 2019. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>For this reason Kevin Watkins and Devi Sridhar called pneumonia <em>“the ultimate disease of poverty”</em> in a 2018 comment in the journal <em>The Lancet</em>.{ref}Watkins, K., & Sridhar, D. (2018). <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31666-0/fulltext">Pneumonia: a global cause without champions.</a><em> The Lancet</em>, <em>392</em>(10149), 718-719.{/ref} There is a very strong correlation between a country’s income and the child mortality rate from pneumonia as the scatter plot shows.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Pneumonia is not a disease that easily spreads across borders, its transmission is generally restricted to local communities and it can be controlled if basic health measures are available. The disease is therefore most common in poor places where healthcare infrastructure is lacking and people are least able to afford the treatment.{ref}The Lancet Global Health Editorial (2018). <a href="https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30495-9/fulltext">The disgraceful neglect of childhood pneumonia.</a><em> The Lancet. Global health</em>, <em>6</em>(12), e1253.{/ref} </p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/pneumonia-death-rates-in-children-under-5" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/death-rates-from-pneumonia-and-other-lower-respiratory-infections-vs-gdp-per-capita?xScale=linear&yScale=linear" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading --> <h2>What are the biggest risks for developing pneumonia?</h2> <!-- /wp:heading --> <!-- wp:heading {"level":3} --> <h3>Why are children dying from pneumonia?</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 27060 --> <!-- wp:columns {"className":"is-style-sticky-right"} --> <div class="wp-block-columns is-style-sticky-right"><!-- wp:column --> <div class="wp-block-column"><!-- wp:paragraph --> <p>To understand how we can reduce the number of children dying from pneumonia we need to understand both prevention and treatment. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In the chart we show the number of child deaths from pneumonia which are attributed to various risk factors. </p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Undernutrition is the major contributor to pneumonia mortality</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Here we see that childhood undernutrition, especially so called ‘<a href="https://ourworldindata.org/grapher/share-of-children-with-a-weight-too-low-for-their-height-wasting">child wasting</a>’ (children who have a weight too low for their height), is the biggest risk factor for pneumonia in children.{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} It contributed to 53% of pneumonia deaths in 2017. Without sufficient energy intake the body cannot cope with increased energy demands required to fight off the infection. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>A literature review of pneumonia in malnourished children by Mohammod Jobayer Chisti and colleagues found that undernourished children are between two and four times more likely to be admitted to hospital due to pneumonia and up to 15 times more likely to die from it.{ref}Chisti, M. J., Tebruegge, M., La Vincente, S., Graham, S. M., & Duke, T. (2009). <a href="https://www.ncbi.nlm.nih.gov/pubmed/19772545?dopt=Abstract">Pneumonia in severely malnourished children in developing countries–mortality risk, aetiology and validity of WHO clinical signs: a systematic review.</a> <em>Tropical medicine & international health</em>, <em>14</em>(10), 1173-1189.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Air pollution and second-hand smoke increase the risk of getting pneumonia </h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p><a href="https://owid.cloud/indoor-air-pollution">Indoor air pollution</a> was the risk factor that is estimated to have lead to 29% of pneumonia deaths in 2017. <a href="https://owid.cloud/outdoor-air-pollution">Outdoor air pollution</a> was responsible for another 18% of all deaths.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Studies have shown that high indoor air pollution in households can double the chances a child develops pneumonia and makes recovery less successful.{ref}Dherani, M., Pope, D., Mascarenhas, M., Smith, K. R., Weber, M., & Bruce, N. (2008). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2647443/">Indoor air pollution from unprocessed solid fuel use and pneumonia risk in children aged under five years: a systematic review and meta-analysis.</a></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><em>Bulletin of the World Health Organization</em> (2006). <a href="http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf">Air quality guidelines: global update 2005.</a> p123-124.{/ref} One of the underlying reasons for why this is the case is that the <a href="https://ourworldindata.org/air-pollution#exposure-to-particulate-matter">small polluting particles</a> impair the immune system’s ability to fight and clear the infection.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Laura Jones et <em>al. </em>(2011) reviewed studies which assessed the impact of secondhand smoke on children, and concluded that children who live in households with smoking parents are more likely to acquire pneumonia as well as other respiratory illnesses. A Global Burden of Disease study by Mattias Öberg et <em>al.</em> has estimated that in 2004, globally around 40% of children lived in households where at least one close relative smoked.{ref}Nel, A. (2005). <a href="https://science.sciencemag.org/content/308/5723/804">Air pollution-related illness: effects of particles</a>. <em>Science</em>, <em>308</em>(5723), 804-806.</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Öberg, M., Jaakkola, M. S., Woodward, A., Peruga, A., & Prüss-Ustün, A. (2011). <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61388-8/fulltext">Worldwide burden of disease from exposure to second-hand smoke: a retrospective analysis of data from 192 countries</a><em>. The Lancet</em>, <em>377</em>(9760), 139-146. The study suggested that exposure to secondhand smoke led to 165,000 deaths among children under 5 from lower respiratory diseases that year.<br>{/ref} The data shown here suggests that the exposure to secondhand smoke led to 61,000 deaths among children under 5 from lower respiratory diseases in 2017.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>The risk of pneumonia is higher for children with HIV</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Exposure to other pathogens such as <a href="https://ourworldindata.org/vaccination#measles-global-vaccination-coverage-and-decline-of-measles">measles</a> and <a href="https://ourworldindata.org/hiv-aids">HIV</a> also increases the risk of pneumonia in children. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>When children who are infected with HIV develop AIDS – which weakens their immune system – their chances of dying from pneumonia increase significantly. A study by Evropi Theodoratou et <em>al., </em>published in <em>Lancet Infectious Diseases,</em> found that children with HIV have a seven times greater risk of dying from pneumonia compared to those without it.{ref}Theodoratou, E., McAllister, D. A., Reed, C., Adeloye, D. O., Rudan, I., Muhe, L. M., … & Nair, H. (2014). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4242006/">Global, regional, and national estimates of pneumonia burden in HIV-infected children in 2010: a meta-analysis and modelling study.</a><em> The Lancet Infectious Diseases</em>, <em>14</em>(12), 1250-1258.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The same study also showed that the proportion of child deaths from pneumonia that can be attributed to HIV varies widely between countries: in 2010 only 1% of all child deaths from pneumonia in India could be directly attributed to HIV, compared to 64% in Eswatini and 62% in Lesotho. In Africa, a total of 3% of cases and 17% of all childhood deaths from pneumonia was attributable to HIV. These regional differences are important to know so that interventions that can save most lives can be prioritized. </p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Overcrowding facilitates pneumonia transmission </h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Pneumonia is not an easily transmittable disease, it requires close contact for the pathogens to be transmitted to another person via air droplets. Therefore overcrowding – too many people living in one space – also increases the risks of pneumonia. This is yet another reason why pneumonia is a disease of poverty: in 2015, 47% of children in low and middle-income countries were living in overcrowded households.{ref}Supplement to: McAllister DA, Liu L, Shi T, et al. <a href="https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf">Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic analysis. </a>Lancet Glob Health 2018; published online Nov 26.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Despite progress against it, more than 800,000 children still die from pneumonia each year. We know where children are dying, and the factors that make them vulnerable to the disease. The key question is how we continue to make progress against it.</p> <!-- /wp:paragraph --></div> <!-- /wp:column --> <!-- wp:column --> <div class="wp-block-column"><!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/pneumonia-risk-factors?time=latest" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --></div> <!-- /wp:column --></div> <!-- /wp:columns --> <!-- wp:heading {"level":3} --> <h3>Pneumonia risk factors for people aged 70 and older</h3> <!-- /wp:heading --> <!-- wp:paragraph --> <p>The risk factors for developing pneumonia in people aged 70 and older are similar to the risk factors that lead to pneumonia in children. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><a href="https://owid.cloud/outdoor-air-pollution">Outdoor air pollution</a> – small particulate matter air pollution – is the risk factor that lead to most deaths. In 2017 it lead to more than 300,000 deaths from pneumonia of older people. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Smoking and exposure to secondhand smoke have contributed to 150,000 and 73,000 deaths from pneumonia in this age group, respectively.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/deaths-from-pneumonia-in-people-aged-70-and-older-by-risk-factor?time=latest" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading --> <h2>How can we reduce the number of people dying from pneumonia?</h2> <!-- /wp:heading --> <!-- wp-block-tombstone 27062 --> <!-- wp:paragraph --> <p>When we understand what risks can lead to pneumonia, we can find ways to reduce them. Furthermore, because a number of risks factors for pneumonia overlap with risk factors for other diseases, <a href="https://ourworldindata.org/childhood-diarrheal-diseases">especially diarrheal diseases</a>, interventions that target pneumonia have the additional benefit of helping to limit other diseases and saving more lives.</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Vaccines against pneumonia</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>There are several versions of <a href="https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine">pneumococcal conjugate vaccine</a> (PCV), which target different serotypes of <em>S. pneumoniae </em>— the bacterium responsible for most cases of pneumonia. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>The PCV vaccine is given to children younger than 24 months. According to a study by Cheryl Cohen et <em>al.</em> (2017), PVC13 – the currently recommended PCV vaccine version – has 85% effectiveness against invasive infections caused by the specific pneumococcal strains<em> </em>included in the vaccine formulation.{ref}Cohen, C., Von Mollendorf, C., De Gouveia, L., Lengana, S., Meiring, S., Quan, V., ... & Madhi, S. A. (2017). <a href="https://www.ncbi.nlm.nih.gov/pubmed/28139443/">Effectiveness of the 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in South African children: a case-control study. </a><em>The Lancet Global Health</em>, <em>5</em>(3), e359-e369.<br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>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).<br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Moore, M. R., Link-Gelles, R., Schaffner, W., Lynfield, R., Holtzman, C., Harrison, L. H., ... & Thomas, A. (2016). <a href="https://www.sciencedirect.com/science/article/abs/pii/S2213260016000527?via%3Dihub">Effectiveness of 13-valent pneumococcal conjugate vaccine for prevention of invasive pneumococcal disease in children in the USA: a matched case-control study.</a> <em>The Lancet Respiratory Medicine</em>, <em>4</em>(5), 399-406.{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>It has been estimated that if PCV13 coverage in low income countries would reach the coverage of the <a href="https://ourworldindata.org/grapher/share-of-children-immunized-dtp3">DTP3 vaccine</a>, then PCV13 could prevent 399,000 child deaths and 54.6 million pneumonia episodes annually when compared with a world in which no pneumococcal vaccination was available.{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} India – which has the highest number of child deaths from pneumonia – only introduced PCV13 in 2017 and the <a href="https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine?tab=chart">coverage is still very low</a> — clearly the pneumococcal vaccine still has a lot of potential.{ref}Read more about pneumococcal vaccines in the <a href="#pneumococcal-vaccines">section below.</a></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>In addition, vaccinating children with PCV can protect adults via <a href="https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity-and-reasons-for-caring-about-broad-vaccination-coverage">herd effect</a>, which means that benefits are not limited to one age group the population — especially important because pneumonia has a <a href="https://docs.google.com/document/d/1IDDdkIyv1oTf-cY444pShF6AxsDRoBYhzUxTSR7sZHw/edit#bookmark=id.j87y55283i1n">significant burden in older people</a>. <br>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}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Another vaccine widely used to protect children against both pneumonia is the <a href="https://ourworldindata.org/grapher/hib-vaccine">Hib vaccine</a>. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Hib immunizes children against <em>Haemophilus influenzae</em> type b, a leading cause of meningitis in children that is also responsible for around 2% of pneumonia deaths of children younger than five years. In 2015 there were around 0.9 million cases of Hib-related pneumonia globally. The Hib immunization provides around 70% protection against Hib-related pneumonia and 84% protection against meningitis in children.{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}</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Promoting breastfeeding</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Encouraging mothers to breastfeed during the first 6 months of a child’s life has a positive impact on reducing child undernutrition, which in turn protects from infectious diseases such as pneumonia. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>According to Laura Lamberti et <em>al. </em>(2013), pneumonia mortality of children in developing countries who are not breastfed in the first 5 months of their lives is 15 times greater than those who exclusively received their mother’s milk.{ref}Lamberti, L. M., Zakarija-Grković, I., Walker, C. L. F., Theodoratou, E., Nair, H., Campbell, H., & Black, R. E. (2013). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3847465/">Breastfeeding for reducing the risk of pneumonia morbidity and mortality in children under two: a systematic literature review and meta-analysis.</a><em> BMC public health</em>, <em>13</em>(3), S18.{/ref} As the map shows, the number of infants who are exclusively breast fed is still low in many countries. Globally, an estimated 41% of infants were exclusively breastfed in 2017.{ref}41% number is estimated by the UNICEF based on the most recent data available for the countries from surveys between 2013-2018. <br>UNICEF DATA. (2019). <a href="https://data.unicef.org/topic/nutrition/infant-and-young-child-feeding/"><em>Infant and young child feeding</em>.</a> [online][Accessed 4 Sep. 2019].{/ref}</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/exclusive-breastfeeding" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Reducing air pollution</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>There has been significant progress in reducing <a href="https://owid.cloud/air-pollution">air pollution</a> levels in recent decades, particularly of <a href="https://owid.cloud/indoor-air-pollution">indoor air pollution</a>. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Death rates from indoor air pollution <a href="https://ourworldindata.org/grapher/death-rate-by-source-from-indoor-air-pollution">fell</a> as a result of <a href="https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking?tab=chart&time=2000..2016&country=OWID_WRL">improved access</a> to cleaner fuels for heating and cooking. But there is still much progress to be made, especially in Sub-Saharan Africa, where in most countries <a href="https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking">less than 10% of households</a> have access to clean fuels for cooking. And, whilst progress has been made against indoor air pollution, high levels of <a href="https://ourworldindata.org/grapher/pm25-air-pollution">outdoor pollution</a> remain a problem across many countries. Reducing air pollution levels would have many other benefits: it would not only reduce the number of cases of pneumonia but also limit the incidence of asthma in children for example.{ref} WHO, U. (2006). <a href="http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf">Air quality guidelines: global update 2005.</a> p123-124. <em>World Health Organization</em>. <br>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Access to healthcare and treatment</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>A child with a suspected case of pneumonia – with symptoms of difficulty in breathing and coughing – should be taken to a healthcare provider so that the correct and immediate treatment can be provided. Delay in seeking treatment can increase the chances of a child dying.{ref}Ferdous, F., Ahmed, S., Das, S. K., Chisti, M. J., Nasrin, D., Kotloff, K. L., ... & Wagatsuma, Y. (2018). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5970515/">Pneumonia mortality and healthcare utilization in young children in rural Bangladesh: a prospective verbal autopsy study.</a><em>Tropical medicine and health</em>, <em>46</em>(1), 17.{/ref} However, as the map shows, seeking healthcare is still not as common as it should be. Globally, less than two-thirds of children with symptoms of pneumonia were taken to a healthcare provider in 2016. This figure is even lower in places where healthcare is most needed — just 47% in Sub-Saharan Africa.{ref} UNICEF DATA. (2018). <a href="https://data.unicef.org/topic/child-health/pneumonia/"><em>Pneumonia in Children</em>.</a> [online] [Accessed 5 Sep. 2019]{/ref} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>As the map shows, the share of children with symptoms of pneumonia that are taken to a health provider is still low in many countries.</p> <!-- /wp:paragraph --> <!-- wp:html --> <iframe src="https://ourworldindata.org/grapher/pneumonia-careseeking" style="width: 100%; height: 600px; border: 0px none;"></iframe> <!-- /wp:html --> <!-- wp:heading {"level":4} --> <h4>Access to antibiotic treatment</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>Given that most cases of pneumonia are of bacterial origin, antibiotics are the general course of treatment. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Due to the lack of resources, in places where pneumonia cases are most common, a quick diagnosis for the cause of disease is not always possible. Given the potential high risk of death from untreated pneumonia, the World Health Organisation (WHO) recommends antibiotic treatment depending on the disease symptoms and its severity before the cause of disease is known. Amoxicillin, ampicillin and gentamicin are the most commonly used antibiotics to treat pneumonia.{ref} World Health Organization. (2014). <a href="https://apps.who.int/iris/bitstream/handle/10665/137319/9789241507813_eng.pdf?sequence=1"><em>Revised WHO classification and treatment of pneumonia in children at health facilities: quick reference guide</em></a> (No. WHO/FWC/MCA/14.9). World Health Organization.{/ref} Antibiotics are a relatively cheap and effective treatment, a course of amoxicillin costs less than 50 cents. {ref}Unicef.org. (2018). <a href="https://www.unicef.org/supply/files/Amoxicillin_DT_Supply_Update.pdf"><em>Amoxicillin Dispersible Tablets: Market and Supply Update</em>.</a> [online] [Accessed 26 Sep. 2019]. {/ref} {ref}Unicef. (2016). <a href="https://www.unicef.org/publications/files/UNICEF_SOWC_2016.pdf">The State of the World's Children 2016</a>. <em>New York: United Nations Children’s Fund</em>.{/ref}</p> <!-- /wp:paragraph --> <!-- wp:heading {"level":4} --> <h4>Oxygen therapy</h4> <!-- /wp:heading --> <!-- wp:paragraph --> <p>During pneumonia, alveoli in the lungs get filled with pus and fluid, which prevents oxygen from being transferred to the blood. Consequently, a condition known as hypoxaemia – a lack of oxygen – can develop. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>When a child with pneumonia develops hypoxaemia the risk of dying increases five-fold.{ref}Lazzerini, M., Sonego, M., & Pellegrin, M. C. (2015). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4570717/">Hypoxaemia as a mortality risk factor in acute lower respiratory infections in children in low and middle-income countries: systematic review and meta-analysis. </a><em>PLoS One</em>, <em>10</em>(9), e0136166.{/ref} Treatment with oxygen therapy (supplying oxygen-enriched air to the patient){ref}The air we breathe contains 21% of oxygen gas, but it is possible to concentrate this gas using special oxygen concentrators. The oxygen-enriched air can then be supplied to a person with pneumonia via a breathing mask, in this way compensating for reduced oxygen exchange in the lungs.{/ref} is one way to mitigate hypoxaemia.{ref}World Health Organization. (2016). <a href="https://www.who.int/maternal_child_adolescent/documents/child-oxygen-therapy/en/">Oxygen therapy for children: a manual for health workers.</a><br>{/ref}</p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>A study from Papua New Guinea has shown that oxygen therapy can reduce the risk of death from severe pneumonia by 35%. However, the need for a specialist equipment to diagnose and treat hypoxaemia still poses a substantial barrier in low-resource settings. Since 2017, the WHO includes oxygen in its List of Essential Medicines.{ref} World Health Organization. (2019). <a href="https://www.who.int/medicines/publications/essentialmedicines/en/">WHO model list of essential medicines: 7th list</a>, August 2019.<br>{/ref} Improved access to oxygen could save the lives of 120,000 children annually.{ref}Delarosa, J., Hayes, J., Pantjushenko, E., Keith, B., Ambler, G. and Lawrence, C. (2017). <a href="https://path.azureedge.net/media/documents/DRG_Oxygen_Primer.pdf"><em>Oxygen Is Essential: A Policy and Advocacy Primer</em></a>. [online] PATH. [Accessed 5 Sep. 2019].{/ref} </p> <!-- /wp:paragraph --> <!-- wp:heading --> <h2>Pneumococcal vaccines</h2> <!-- /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 --> <h2>Additional Information</h2> <!-- /wp:heading --> <!-- wp:heading {"level":3} --> <h3>What pathogens cause pneumonia?</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 27054 --> <!-- wp:paragraph --> <p>Pneumonia is an infection of the lower respiratory tract that can be caused by multiple microbial pathogens. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>By far the most common cause of pneumonia in unvaccinated children is an infection by a bacterium called <em>Streptococcus pneumoniae</em>, simply referred to as pneumococcus. The Global Burden of Disease (GBD) study from 2018 has estimated that pneumococcus<em> </em>was responsible for 52% of 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> </em><em>The Lancet Infectious Diseases</em>, <em>18</em>(11), 1191-1210.{/ref} <br></p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Other pathogens which cause pneumonia in children are <em>Haemophilus influenzae</em> type b, respiratory syncytial virus (RSV), and the influenza virus. Each of these pathogens was responsible for less than 4% of lethal pneumonia cases 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> </em><em>The Lancet Infectious Diseases</em>, <em>18</em>(11), 1191-1210.{/ref} Despite being minor causes, it’s important to continue developing treatments against these pathogens; they will become increasingly important as vaccination coverage for the most common causes increases. According to a study by Katherine O'Brien et <em>al.</em> (2019), when children are routinely vaccinated with pneumococcal and Hib vaccines, as many as 62% of pneumonia cases are caused by viral pathogens such as RSV.{ref}O'Brien, K. L., Baggett, H. C., Brooks, W. A., Feikin, D. R., Hammitt, L. L., Higdon, M. M., ... & Madhi, S. A. (2019). <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)30721-4/fulltext">Causes of severe pneumonia requiring hospital admission in children without HIV infection from Africa and Asia: the PERCH multi-country case-control study.</a><em> The Lancet</em>. {/ref} </p> <!-- /wp:paragraph --> <!-- wp:heading {"level":3} --> <h3>How is pneumonia acquired and transmitted?</h3> <!-- /wp:heading --> <!-- wp-block-tombstone 27056 --> <!-- wp:paragraph --> <p>Children can contract pneumonia in a number of ways. Pneumococcus and <em>H. influenzae </em>are bacteria that can be found in the upper respiratory tract of healthy individuals without any symptoms. Under circumstances when the conditions in the upper respiratory tract are compromised{ref}For example, when a secondary infection with a virus occurs, which may trigger multiplication of usually non-pathogenic bacteria.{/ref} these normally benign bacteria may move to the lower respiratory tract where they lead to pneumonia.{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} </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p>Pneumonia caused by bacterial and viral pathogens can be contagious and transmitted when a person coughs or sneezes. However, precautions such as sanitizing hands and surfaces, wearing a face mask if available and limiting close contact with a sick person can significantly limit the chances of transmission. </p> <!-- /wp:paragraph --> <!-- wp:paragraph --> <p><br></p> <!-- /wp:paragraph --> | { "id": "wp-26939", "slug": "pneumonia", "content": { "toc": [], "body": [ { "type": "text", "value": [ { "text": "This entry was first published in November 2019.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "2.5 million people died from pneumonia in 2019. Almost a third of all victims were children younger than 5 years, it is the leading cause of death for children under 5.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Pneumonia is an infection of the tiny air sacs of the lungs, called alveoli. In a person with pneumonia the alveoli are filled with pus and fluid, which makes breathing painful and reduces the oxygen intake. Pneumonia is caused by a number of different infectious agents, including viruses, bacteria and fungi.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Here in this research entry we look at who is suffering from pneumonia and why \u2013 and what can we do to reduce the number of people dying from this disease. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "entry-summary", "items": [ { "slug": "burden-of-pneumonia", "text": "Pneumonia is the leading cause of death for children under 5 \u2014 more than 800,000 children died due to pneumonia in 2017." }, { "slug": "burden-of-pneumonia", "text": "While still too many children die today, since 1990 we\u2019ve seen more than 3-fold reduction in child mortality rates from pneumonia globally." }, { "slug": "pneumonia-mortality-rates-by-age", "text": "The global mortality rates for older people remained unchanged since 1990." }, { "slug": "where-do-children-die-from-pneumonia", "text": "Mortality from pneumonia is highest in Sub-Saharan Africa." }, { "slug": "what-are-the-biggest-risks-for-developing-pneumonia", "text": "The greatest risk factors for developing pneumonia are undernutrition, air pollution and smoking." }, { "slug": "how-can-we-reduce-the-number-of-people-dying-from-pneumonia", "text": "Reducing exposure to risk factors and higher coverage of pneumococcal vaccines can reduce the number deaths from pneumonia." }, { "slug": "pneumococcal-vaccines", "text": "Research suggests that pneumococcal vaccines could be saving the lives of almost 400,000 children annually." } ], "parseErrors": [] }, { "text": [ { "text": "Estimates that refer to pneumonia might also include cases of other lower respiratory diseases", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Ideally, pneumonia would always be diagnosed by a physician using radiological imaging and determining the infectious agent that caused the disease. However, because such diagnosis requires a lot of resources, it is in many cases not done.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "This is why research literature uses the terms 'clinical pneumonia' or 'WHO-pneumonia' to diagnoses based on ", "spanType": "span-simple-text" }, { "children": [ { "text": "symptoms", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (most importantly, fast breathing and coughing). A symptoms-based definition inevitably means that diseases with similar symptoms may be counted as cases of pneumonia.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "As a consequence the terms pneumonia and lower respiratory infections (LRIs) are often used interchangeably. The ", "spanType": "span-simple-text" }, { "children": [ { "text": "Institute for Health Metrics and Evaluation ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(IHME), for example, provides mortality data on LRIs, in which they include pneumonia caused by a range of different pathogens, but they also include bronchiolitis, a lower respiratory tract infection that mostly affects very young children, in this category.{ref}Institute for Health Metrics and Evaluation (IMHE). (2014). ", "spanType": "span-simple-text" }, { "url": "http://www.healthdata.org/sites/default/files/files/policy_report/2014/PolicyReport_IHME_PushingthePace_2014.pdf", "children": [ { "text": "Pushing the Pace: Progress and Challenges in Fighting Childhood Pneumonia.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "{/ref} {ref}McAllister, D. A., Liu, L., Shi, T., Chu, Y., Reed, C., Burrows, J., ... & Nair, H. (2019). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf", "children": [ { "text": "Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic 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), e47-e57.{/ref} While cases of bronchiolitis are quite common they are generally not fatal, therefore, it is reasonable to assume that the bulk of IHME estimates for the number of deaths from lower respiratory diseases do refer to deaths from pneumonia.\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Burden of pneumonia", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Number of people dying from pneumonia by age", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the visualization here we see the global number of deaths from pneumonia{ref}We use the term pneumonia here as a broad term for lower respiratory infections, see ", "spanType": "span-simple-text" }, { "url": "#estimates-that-refer-to-pneumonia-might-also-include-cases-of-other-lower-respiratory-diseases", "children": [ { "text": "this section", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " for how these terms are defined and why they are grouped together.{/ref} by age group.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "15% of all ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/child-mortality", "children": [ { "text": "child deaths", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " in 2017 were caused by pneumonia and it is therefore the leading cause of death of children (see our discussion ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/child-mortality#what-are-children-dying-from", "children": [ { "text": "here", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ").", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The number of children dying from pneumonia has decreased substantially over the past three decades. In 1990, more than two million children died from pneumonia every year. By 2017, this number had fallen by almost two-thirds. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Improvements in the major risk factors such as ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/hunger-and-undernourishment#too-little-weight-for-height-wasting", "children": [ { "text": "childhood wasting", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/air-pollution", "children": [ { "text": "air pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", and ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/death-rate-from-unsafe-sanitation", "children": [ { "text": "poor sanitation", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", falling ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/extreme-poverty", "children": [ { "text": "global poverty", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", and a better availability of health technology such as pneumococcal vaccines and antibiotics have all contributed to this decline.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "While the death ", "spanType": "span-simple-text" }, { "children": [ { "text": "rate", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " for old people fell slightly, the ", "spanType": "span-simple-text" }, { "children": [ { "text": "number", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " of deaths of people who are 70 years and older increased. ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths", "children": [ { "text": "1.13 million", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", who died from pneumonia where in this age group. This is because the number of people who reached the age of 70 increased very strongly globally as we show in ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/age-structure", "children": [ { "text": "our entry", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " on the changing global age structure. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Pneumonia mortality rates by age", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The chart shows the annual number of deaths from pneumonia per 100,000 people in different age groups.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Looking at the age-group of under 5 year olds we see that there has been a 3-fold reduction in child mortality due to pneumonia over the last three decades. 363 children out of every 100,000 died due to pneumonia in 1990, until 2017 that number has fallen to 119.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The mortality rates among other age groups have remained largely the same. The highest pneumonia mortality rates in 2017 were among people aged 70 and older. 261 out of 100,000 people died in this age group due to pneumonia. That's a 9% decrease in mortality rates over the past 3 decades.{ref}(286.1-260.9)/286.1=0.09{/ref} ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/pneumonia-mortality-by-age", "type": "chart", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Where do people die from pneumonia?", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Pneumonia death rates \u2013 all ages", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the map we see the death rate from pneumonia expressed as the number of deaths due to pneumonia per year per 100,000 individuals. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "We can see that the death rate from pneumonia is highest in Sub-Saharan Africa and Southeast-Asia. The difference between richer and poorer countries is large: European populations suffer a rate of around 10 deaths per 100,000 while poorer countries see rate of more than 100 deaths per 100,000 is ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In Southeast-Asia, the population of the Philippines suffer from particularly high pneumonia mortality rates; pneumonia is the second leading cause of death in both under-5-year-old and ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/pneumonia-death-rates-70", "children": [ { "text": "older than 70", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "-year-old populations in this country. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "These rates have been age-standardized, which tells us the death rate for each country and each point in time as if the age structure of a population. This therefore allows us to make across comparisons across countries and through time that are not affected by differences in the age-structure between countries and changes of the age-structure over time.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/pneumonia-death-rates-70", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Where do children die from pneumonia", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The map shows the number of child deaths due to pneumonia per 100,000 children per year.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "It shows that children are most likely to die from pneumonia across Sub-Saharan Africa and South Asia. The deaths in just ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5", "children": [ { "text": "5 countries", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2014 India, Nigeria, Pakistan, the Democratic Republic of Congo, and Ethiopia \u2013 accounted for more than half of all deaths from childhood pneumonia in 2019.\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "For this reason Kevin Watkins and Devi Sridhar called pneumonia ", "spanType": "span-simple-text" }, { "children": [ { "text": "\u201cthe ultimate disease of poverty\u201d", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " in a 2018 comment in the journal ", "spanType": "span-simple-text" }, { "children": [ { "text": "The Lancet", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".{ref}Watkins, K., & Sridhar, D. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31666-0/fulltext", "children": [ { "text": "Pneumonia: a global cause without champions.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " The Lancet", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "392", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(10149), 718-719.{/ref} There is a very strong correlation between a country\u2019s income and the child mortality rate from pneumonia as the scatter plot shows.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Pneumonia is not a disease that easily spreads across borders, its transmission is generally restricted to local communities and it can be controlled if basic health measures are available. The disease is therefore most common in poor places where healthcare infrastructure is lacking and people are least able to afford the treatment.{ref}The Lancet Global Health Editorial (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30495-9/fulltext", "children": [ { "text": "The disgraceful neglect of childhood pneumonia.", "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": "(12), e1253.{/ref} ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/pneumonia-death-rates-in-children-under-5", "type": "chart", "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/death-rates-from-pneumonia-and-other-lower-respiratory-infections-vs-gdp-per-capita?xScale=linear&yScale=linear", "type": "chart", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "What are the biggest risks for developing pneumonia?", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Why are children dying from pneumonia?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "To understand how we can reduce the number of children dying from pneumonia we need to understand both prevention and treatment.\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In the chart we show the number of child deaths from pneumonia which are attributed to various risk factors.\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Undernutrition is the major contributor to pneumonia mortality", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Here we see that childhood undernutrition, especially so called \u2018", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-children-with-a-weight-too-low-for-their-height-wasting", "children": [ { "text": "child wasting", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "\u2019 (children who have a weight too low for their height), is the biggest risk factor for pneumonia in children.{ref}Troeger, C., Blacker, B., Khalil, I. A., Rao, P. C., Cao, J., Zimsen, S. R., \u2026 & 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} It contributed to 53% of pneumonia deaths in 2017. Without sufficient energy intake the body cannot cope with increased energy demands required to fight off the infection. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "A literature review of pneumonia in malnourished children by Mohammod Jobayer Chisti and colleagues found that undernourished children are between two and four times more likely to be admitted to hospital due to pneumonia and up to 15 times more likely to die from it.{ref}Chisti, M. J., Tebruegge, M., La Vincente, S., Graham, S. M., & Duke, T. (2009). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/19772545?dopt=Abstract", "children": [ { "text": "Pneumonia in severely malnourished children in developing countries\u2013mortality risk, aetiology and validity of WHO clinical signs: a systematic review.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "Tropical medicine & international health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "14", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(10), 1173-1189.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Air pollution and second-hand smoke increase the risk of getting pneumonia\u00a0", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "url": "https://owid.cloud/indoor-air-pollution", "children": [ { "text": "Indoor air pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " was the risk factor that is estimated to have lead to 29% of pneumonia deaths in 2017. ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/outdoor-air-pollution", "children": [ { "text": "Outdoor air pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " was responsible for another 18% of all deaths.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Studies have shown that high indoor air pollution in households can double the chances a child develops pneumonia and makes recovery less successful.{ref}Dherani, M., Pope, D., Mascarenhas, M., Smith, K. R., Weber, M., & Bruce, N. (2008). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2647443/", "children": [ { "text": "Indoor air pollution from unprocessed solid fuel use and pneumonia risk in children aged under five years: a systematic review and meta-analysis.", "spanType": "span-simple-text" } ], "spanType": "span-link" } ], "parseErrors": [] }, { "type": "text", "value": [ { "children": [ { "text": "Bulletin of the World Health Organization", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (2006). ", "spanType": "span-simple-text" }, { "url": "http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf", "children": [ { "text": "Air quality guidelines: global update 2005.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " p123-124.{/ref} One of the underlying reasons for why this is the case is that the ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/air-pollution#exposure-to-particulate-matter", "children": [ { "text": "small polluting particles", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " impair the immune system\u2019s ability to fight and clear the infection.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Laura Jones et ", "spanType": "span-simple-text" }, { "children": [ { "text": "al. ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(2011) reviewed studies which assessed the impact of secondhand smoke on children, and concluded that children who live in households with smoking parents are more likely to acquire pneumonia as well as other respiratory illnesses. A Global Burden of Disease study by Mattias \u00d6berg et ", "spanType": "span-simple-text" }, { "children": [ { "text": "al.", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " has estimated that in 2004, globally around 40% of children lived in households where at least one close relative smoked.{ref}Nel, A. (2005). ", "spanType": "span-simple-text" }, { "url": "https://science.sciencemag.org/content/308/5723/804", "children": [ { "text": "Air pollution-related illness: effects of particles", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "Science", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "308", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(5723), 804-806.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "\u00d6berg, M., Jaakkola, M. S., Woodward, A., Peruga, A., & Pr\u00fcss-Ust\u00fcn, A. (2011). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61388-8/fulltext", "children": [ { "text": "Worldwide burden of disease from exposure to second-hand smoke: a retrospective analysis of data from 192 countries", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": ". The Lancet", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "377", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(9760), 139-146. The study suggested that exposure to secondhand smoke led to 165,000 deaths among children under 5 from lower respiratory diseases that year.", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "{/ref} The data shown here suggests that the exposure to secondhand smoke led to 61,000 deaths among children under 5 from lower respiratory diseases in 2017.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "The risk of pneumonia is higher for children with HIV", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Exposure to other pathogens such as ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/vaccination#measles-global-vaccination-coverage-and-decline-of-measles", "children": [ { "text": "measles", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " and ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/hiv-aids", "children": [ { "text": "HIV", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " also increases the risk of pneumonia in children. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "When children who are infected with HIV develop AIDS \u2013 which weakens their immune system \u2013 their chances of dying from pneumonia increase significantly. A study by Evropi Theodoratou et ", "spanType": "span-simple-text" }, { "children": [ { "text": "al., ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "published in ", "spanType": "span-simple-text" }, { "children": [ { "text": "Lancet Infectious Diseases,", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " found that children with HIV have a seven times greater risk of dying from pneumonia compared to those without it.{ref}Theodoratou, E., McAllister, D. A., Reed, C., Adeloye, D. O., Rudan, I., Muhe, L. M., \u2026 & Nair, H. (2014). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4242006/", "children": [ { "text": "Global, regional, and national estimates of pneumonia burden in HIV-infected children in 2010: a meta-analysis and modelling study.", "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": "14", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(12), 1250-1258.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The same study also showed that the proportion of child deaths from pneumonia that can be attributed to HIV varies widely between countries: in 2010 only 1% of all child deaths from pneumonia in India could be directly attributed to HIV, compared to 64% in Eswatini and 62% in Lesotho. In Africa, a total of 3% of cases and 17% of all childhood deaths from pneumonia was attributable to HIV. These regional differences are important to know so that interventions that can save most lives can be prioritized.\u00a0 ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Overcrowding facilitates pneumonia transmission\u00a0", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Pneumonia is not an easily transmittable disease, it requires close contact for the pathogens to be transmitted to another person via air droplets. Therefore overcrowding \u2013 too many people living in one space \u2013 also increases the risks of pneumonia. This is yet another reason why pneumonia is a disease of poverty: in 2015, 47% of children in low and middle-income countries were living in overcrowded households.{ref}Supplement to: McAllister DA, Liu L, Shi T, et al. ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf", "children": [ { "text": "Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic analysis. ", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": "Lancet Glob Health 2018; published online Nov 26.{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Despite progress against it, more than 800,000 children still die from pneumonia each year. We know where children are dying, and the factors that make them vulnerable to the disease. The key question is how we continue to make progress against it.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/pneumonia-risk-factors?time=latest", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Pneumonia risk factors for people aged 70 and older", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "The risk factors for developing pneumonia in people aged 70 and older are similar to the risk factors that lead to pneumonia in children. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "url": "https://owid.cloud/outdoor-air-pollution", "children": [ { "text": "Outdoor air pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2013 small particulate matter air pollution \u2013 is the risk factor that lead to most deaths. In 2017 it lead to more than 300,000 deaths from pneumonia of older people. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Smoking and exposure to secondhand smoke have contributed to 150,000 and 73,000 deaths from pneumonia in this age group, respectively.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/deaths-from-pneumonia-in-people-aged-70-and-older-by-risk-factor?time=latest", "type": "chart", "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "How can we reduce the number of people dying from pneumonia?", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "type": "text", "value": [ { "text": "When we understand what risks can lead to pneumonia, we can find ways to reduce them. Furthermore, because a number of risks factors for pneumonia overlap with risk factors for other diseases, ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/childhood-diarrheal-diseases", "children": [ { "text": "especially diarrheal diseases", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", interventions that target pneumonia have the additional benefit of helping to limit other diseases and saving more lives.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Vaccines against pneumonia", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "There are several versions of ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine", "children": [ { "text": "pneumococcal conjugate vaccine", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " (PCV), which target different serotypes of ", "spanType": "span-simple-text" }, { "children": [ { "text": "S. pneumoniae ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "\u2014 the bacterium responsible for most cases of pneumonia. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "The PCV vaccine is given to children younger than 24 months. According to a study by Cheryl Cohen et ", "spanType": "span-simple-text" }, { "children": [ { "text": "al.", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (2017), PVC13 \u2013 the currently recommended PCV vaccine version \u2013 has 85% effectiveness against invasive infections caused by the specific pneumococcal strains", "spanType": "span-simple-text" }, { "children": [ { "text": " ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "included in the vaccine formulation.{ref}Cohen, C., Von Mollendorf, C., De Gouveia, L., Lengana, S., Meiring, S., Quan, V., ... & Madhi, S. A. (2017). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pubmed/28139443/", "children": [ { "text": "Effectiveness of the 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in South African children: a case-control study. ", "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": "5", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(3), e359-e369.", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Lucero, 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" }, { "children": [ { "text": "Cochrane Database of Systematic Reviews", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", (4).", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Moore, M. R., Link-Gelles, R., Schaffner, W., Lynfield, R., Holtzman, C., Harrison, L. H., ... & Thomas, A. (2016). ", "spanType": "span-simple-text" }, { "url": "https://www.sciencedirect.com/science/article/abs/pii/S2213260016000527?via%3Dihub", "children": [ { "text": "Effectiveness of 13-valent pneumococcal conjugate vaccine for prevention of invasive pneumococcal disease in children in the USA: a matched case-control study.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "The Lancet Respiratory Medicine", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "4", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(5), 399-406.{/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "It has been estimated that if PCV13 coverage in low income countries would reach the coverage of the ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-children-immunized-dtp3", "children": [ { "text": "DTP3 vaccine", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", then PCV13 could prevent 399,000 child deaths and 54.6 million pneumonia episodes annually when compared with a world in which no pneumococcal vaccination was available.{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} India \u2013 which has the highest number of child deaths from pneumonia \u2013 only introduced PCV13 in 2017 and the ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine?tab=chart", "children": [ { "text": "coverage is still very low", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " \u2014 clearly the pneumococcal vaccine still has a lot of potential.{ref}Read more about pneumococcal vaccines in the ", "spanType": "span-simple-text" }, { "url": "#pneumococcal-vaccines", "children": [ { "text": "section below.", "spanType": "span-simple-text" } ], "spanType": "span-link" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "In addition, vaccinating children with PCV can protect adults via ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity-and-reasons-for-caring-about-broad-vaccination-coverage", "children": [ { "text": "herd effect", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", which means that benefits are not limited to one age group the population \u2014 especially important because pneumonia has a ", "spanType": "span-simple-text" }, { "url": "https://docs.google.com/document/d/1IDDdkIyv1oTf-cY444pShF6AxsDRoBYhzUxTSR7sZHw/edit#bookmark=id.j87y55283i1n", "children": [ { "text": "significant burden in older people", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ".\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "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}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Another vaccine widely used to protect children against both pneumonia is the ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/hib-vaccine", "children": [ { "text": "Hib vaccine", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Hib immunizes children against ", "spanType": "span-simple-text" }, { "children": [ { "text": "Haemophilus influenzae", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " type b, a leading cause of meningitis in children that is also responsible for around 2% of pneumonia deaths of children younger than five years. In 2015 there were around 0.9 million cases of Hib-related pneumonia globally. The Hib immunization provides around 70% protection against Hib-related pneumonia and 84% protection against meningitis in children.{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}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Promoting breastfeeding", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Encouraging mothers to breastfeed during the first 6 months of a child\u2019s life has a positive impact on reducing child undernutrition, which in turn protects from infectious diseases such as pneumonia. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "According to Laura Lamberti et ", "spanType": "span-simple-text" }, { "children": [ { "text": "al. ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(2013), pneumonia mortality of children in developing countries who are not breastfed in the first 5 months of their lives is 15 times greater than those who exclusively received their mother\u2019s milk.{ref}Lamberti, L. M., Zakarija-Grkovi\u0107, I., Walker, C. L. F., Theodoratou, E., Nair, H., Campbell, H., & Black, R. E. (2013). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3847465/", "children": [ { "text": "Breastfeeding for reducing the risk of pneumonia morbidity and mortality in children under two: a systematic literature review and meta-analysis.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " BMC public health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "13", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(3), S18.{/ref} As the map shows, the number of infants who are exclusively breast fed is still low in many countries. Globally, an estimated 41% of infants were exclusively breastfed in 2017.{ref}41% number is estimated by the UNICEF based on the most recent data available for the countries from surveys between 2013-2018.\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "UNICEF DATA. (2019). ", "spanType": "span-simple-text" }, { "url": "https://data.unicef.org/topic/nutrition/infant-and-young-child-feeding/", "children": [ { "children": [ { "text": "Infant and young child feeding", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " [online][Accessed 4 Sep. 2019].{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/exclusive-breastfeeding", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Reducing air pollution", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "There has been significant progress in reducing ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/air-pollution", "children": [ { "text": "air pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " levels in recent decades, particularly of ", "spanType": "span-simple-text" }, { "url": "https://owid.cloud/indoor-air-pollution", "children": [ { "text": "indoor air pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Death rates from indoor air pollution ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/death-rate-by-source-from-indoor-air-pollution", "children": [ { "text": "fell", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " as a result of ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking?tab=chart&time=2000..2016&country=OWID_WRL", "children": [ { "text": "improved access", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " to cleaner fuels for heating and cooking. But there is still much progress to be made, especially in Sub-Saharan Africa, where in most countries ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking", "children": [ { "text": "less than 10% of households", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " have access to clean fuels for cooking. And, whilst progress has been made against indoor air pollution, high levels of ", "spanType": "span-simple-text" }, { "url": "https://ourworldindata.org/grapher/pm25-air-pollution", "children": [ { "text": "outdoor pollution", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " remain a problem across many countries. Reducing air pollution levels would have many other benefits: it would not only reduce the number of cases of pneumonia but also limit the incidence of asthma in children for example.{ref}\u00a0WHO, U. (2006). ", "spanType": "span-simple-text" }, { "url": "http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf", "children": [ { "text": "Air quality guidelines: global update 2005.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " p123-124. ", "spanType": "span-simple-text" }, { "children": [ { "text": "World Health Organization", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Access to healthcare and treatment", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "A child with a suspected case of pneumonia \u2013 with symptoms of difficulty in breathing and coughing \u2013 should be taken to a healthcare provider so that the correct and immediate treatment can be provided. Delay in seeking treatment can increase the chances of a child dying.{ref}Ferdous, F., Ahmed, S., Das, S. K., Chisti, M. J., Nasrin, D., Kotloff, K. L., ... & Wagatsuma, Y. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5970515/", "children": [ { "text": "Pneumonia mortality and healthcare utilization in young children in rural Bangladesh: a prospective verbal autopsy study.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "Tropical medicine and health", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "46", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(1), 17.{/ref} However, as the map shows, seeking healthcare is still not as common as it should be. Globally, less than two-thirds of children with symptoms of pneumonia were taken to a healthcare provider in 2016. This figure is even lower in places where healthcare is most needed \u2014 just 47% in Sub-Saharan Africa.{ref}\u00a0UNICEF DATA. (2018). ", "spanType": "span-simple-text" }, { "url": "https://data.unicef.org/topic/child-health/pneumonia/", "children": [ { "children": [ { "text": "Pneumonia in Children", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " [online] [Accessed 5 Sep. 2019]{/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "As the map shows, the share of children with symptoms of pneumonia that are taken to a health provider is still low in many countries.", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "url": "https://ourworldindata.org/grapher/pneumonia-careseeking", "type": "chart", "parseErrors": [] }, { "text": [ { "text": "Access to antibiotic treatment", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Given that most cases of pneumonia are of bacterial origin, antibiotics are the general course of treatment. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Due to the lack of resources, in places where pneumonia cases are most common, a quick diagnosis for the cause of disease is not always possible. Given the potential high risk of death from untreated pneumonia, the World Health Organisation (WHO) recommends antibiotic treatment depending on the disease symptoms and its severity before the cause of disease is known. Amoxicillin, ampicillin and gentamicin are the most commonly used antibiotics to treat pneumonia.{ref}\u00a0World Health Organization. (2014). ", "spanType": "span-simple-text" }, { "url": "https://apps.who.int/iris/bitstream/handle/10665/137319/9789241507813_eng.pdf?sequence=1", "children": [ { "children": [ { "text": "Revised WHO classification and treatment of pneumonia in children at health facilities: quick reference guide", "spanType": "span-simple-text" } ], "spanType": "span-italic" } ], "spanType": "span-link" }, { "text": " (No. WHO/FWC/MCA/14.9). World Health Organization.{/ref} Antibiotics are a relatively cheap and effective treatment, a course of amoxicillin costs less than 50 cents. {ref}Unicef.org. (2018). ", "spanType": "span-simple-text" }, { "url": "https://www.unicef.org/supply/files/Amoxicillin_DT_Supply_Update.pdf", "children": [ { "children": [ { "text": "Amoxicillin Dispersible Tablets: Market and Supply Update", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": " [online] [Accessed 26 Sep. 2019]. {/ref} {ref}Unicef. (2016). ", "spanType": "span-simple-text" }, { "url": "https://www.unicef.org/publications/files/UNICEF_SOWC_2016.pdf", "children": [ { "text": "The State of the World's Children 2016", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ". ", "spanType": "span-simple-text" }, { "children": [ { "text": "New York: United Nations Children\u2019s Fund", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ".{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "Oxygen therapy", "spanType": "span-simple-text" } ], "type": "heading", "level": 3, "parseErrors": [] }, { "type": "text", "value": [ { "text": "During pneumonia, alveoli in the lungs get filled with pus and fluid, which prevents oxygen from being transferred to the blood. Consequently, a condition known as hypoxaemia \u2013 a lack of oxygen \u2013 can develop. ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "When a child with pneumonia develops hypoxaemia the risk of dying increases five-fold.{ref}Lazzerini, M., Sonego, M., & Pellegrin, M. C. (2015). ", "spanType": "span-simple-text" }, { "url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4570717/", "children": [ { "text": "Hypoxaemia as a mortality risk factor in acute lower respiratory infections in children in low and middle-income countries: systematic review and meta-analysis. ", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": "PLoS One", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", ", "spanType": "span-simple-text" }, { "children": [ { "text": "10", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "(9), e0136166.{/ref} Treatment with oxygen therapy (supplying oxygen-enriched air to the patient){ref}The air we breathe contains 21% of oxygen gas, but it is possible to concentrate this gas using special oxygen concentrators. The oxygen-enriched air can then be supplied to a person with pneumonia via a breathing mask, in this way compensating for reduced oxygen exchange in the lungs.{/ref} is one way to mitigate hypoxaemia.{ref}World Health Organization. (2016). ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/maternal_child_adolescent/documents/child-oxygen-therapy/en/", "children": [ { "text": "Oxygen therapy for children: a manual for health workers.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "spanType": "span-newline" }, { "text": "{/ref}", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "A study from Papua New Guinea has shown that oxygen therapy can reduce the risk of death from severe pneumonia by 35%. However, the need for a specialist equipment to diagnose and treat hypoxaemia still poses a substantial barrier in low-resource settings. Since 2017, the WHO includes oxygen in its List of Essential Medicines.{ref}\u00a0World Health Organization. (2019). ", "spanType": "span-simple-text" }, { "url": "https://www.who.int/medicines/publications/essentialmedicines/en/", "children": [ { "text": "WHO model list of essential medicines: 7th list", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "text": ", August 2019.", "spanType": "span-simple-text" }, { "spanType": "span-newline" }, { "text": "{/ref} Improved access to oxygen could save the lives of 120,000 children annually.{ref}Delarosa, J., Hayes, J., Pantjushenko, E., Keith, B., Ambler, G. and Lawrence, C. (2017). ", "spanType": "span-simple-text" }, { "url": "https://path.azureedge.net/media/documents/DRG_Oxygen_Primer.pdf", "children": [ { "children": [ { "text": "Oxygen Is Essential: A Policy and Advocacy Primer", "spanType": "span-simple-text" } ], "spanType": "span-italic" } ], "spanType": "span-link" }, { "text": ". [online] PATH. [Accessed 5 Sep. 2019].{/ref}\u00a0\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Pneumococcal vaccines", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "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": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "Additional Information", "spanType": "span-simple-text" } ], "type": "heading", "level": 1, "parseErrors": [] }, { "type": "horizontal-rule", "parseErrors": [] }, { "text": [ { "text": "What pathogens cause pneumonia?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Pneumonia is an infection of the lower respiratory tract that can be caused by multiple microbial pathogens.\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "By far the most common cause of pneumonia in unvaccinated children is an infection by a bacterium called ", "spanType": "span-simple-text" }, { "children": [ { "text": "Streptococcus pneumoniae", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ", simply referred to as pneumococcus. The Global Burden of Disease (GBD) study from 2018 has estimated that pneumococcus", "spanType": "span-simple-text" }, { "children": [ { "text": " ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "was responsible for 52% of 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": " ", "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": "(11), 1191-1210.{/ref}\u00a0", "spanType": "span-simple-text" }, { "spanType": "span-newline" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Other pathogens which cause pneumonia in children are ", "spanType": "span-simple-text" }, { "children": [ { "text": "Haemophilus influenzae", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " type b, respiratory syncytial virus (RSV), and the influenza virus. Each of these pathogens was responsible for less than 4% of lethal pneumonia cases 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": " ", "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": "(11), 1191-1210.{/ref} Despite being minor causes, it\u2019s important to continue developing treatments against these pathogens; they will become increasingly important as vaccination coverage for the most common causes increases. According to a study by Katherine O'Brien et ", "spanType": "span-simple-text" }, { "children": [ { "text": "al.", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": " (2019), when children are routinely vaccinated with pneumococcal and Hib vaccines, as many as 62% of pneumonia cases are caused by viral pathogens such as RSV.{ref}O'Brien, K. L., Baggett, H. C., Brooks, W. A., Feikin, D. R., Hammitt, L. L., Higdon, M. M., ... & Madhi, S. A. (2019). ", "spanType": "span-simple-text" }, { "url": "https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)30721-4/fulltext", "children": [ { "text": "Causes of severe pneumonia requiring hospital admission in children without HIV infection from Africa and Asia: the PERCH multi-country case-control study.", "spanType": "span-simple-text" } ], "spanType": "span-link" }, { "children": [ { "text": " The Lancet", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": ". {/ref}\u00a0", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "text": [ { "text": "How is pneumonia acquired and transmitted?", "spanType": "span-simple-text" } ], "type": "heading", "level": 2, "parseErrors": [] }, { "type": "text", "value": [ { "text": "Children can contract pneumonia in a number of ways. Pneumococcus and ", "spanType": "span-simple-text" }, { "children": [ { "text": "H. influenzae ", "spanType": "span-simple-text" } ], "spanType": "span-italic" }, { "text": "are bacteria that can be found in the upper respiratory tract of healthy individuals without any symptoms. Under circumstances when the conditions in the upper respiratory tract are compromised{ref}For example, when a secondary infection with a virus occurs, which may trigger multiplication of usually non-pathogenic bacteria.{/ref} these normally benign bacteria may move to the lower respiratory tract where they lead to pneumonia.{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} ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "text": "Pneumonia caused by bacterial and viral pathogens can be contagious and transmitted when a person coughs or sneezes. However, precautions such as sanitizing hands and surfaces, wearing a face mask if available and limiting close contact with a sick person can significantly limit the chances of transmission.\u00a0 \u00a0 ", "spanType": "span-simple-text" } ], "parseErrors": [] }, { "type": "text", "value": [ { "spanType": "span-newline" } ], "parseErrors": [] } ], "type": "linear-topic-page", "title": "Pneumonia", "authors": [ "Bernadeta Dadonaite", "Max Roser" ], "excerpt": "Pneumonia is the leading cause of death for children younger than 5 years.", "dateline": "November 4, 2018", "subtitle": "Pneumonia is the leading cause of death for children younger than 5 years.", "sticky-nav": [], "sidebar-toc": true, "featured-image": "Screen-Shot-2021-04-02-at-11.08.49.png" }, "createdAt": "2019-11-05T10:40:58.000Z", "published": false, "updatedAt": "2022-03-04T16:19:48.000Z", "revisionId": null, "publishedAt": "2018-11-04T12:09:26.000Z", "relatedCharts": [], "publicationContext": "listed" } |
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2018-11-04 12:09:26 | 2024-02-16 14:22:39 | [ "Bernadeta Dadonaite" ] |
Pneumonia is the leading cause of death for children younger than 5 years. | 2019-11-05 10:40:58 | 2022-03-04 16:19:48 | https://ourworldindata.org/wp-content/uploads/2021/04/Screen-Shot-2021-04-02-at-11.08.49.png | {} |
This entry was first published in November 2019. 2.5 million people died from pneumonia in 2019. Almost a third of all victims were children younger than 5 years, it is the leading cause of death for children under 5. Pneumonia is an infection of the tiny air sacs of the lungs, called alveoli. In a person with pneumonia the alveoli are filled with pus and fluid, which makes breathing painful and reduces the oxygen intake. Pneumonia is caused by a number of different infectious agents, including viruses, bacteria and fungi. Here in this research entry we look at who is suffering from pneumonia and why – and what can we do to reduce the number of people dying from this disease. ### Estimates that refer to pneumonia might also include cases of other lower respiratory diseases Ideally, pneumonia would always be diagnosed by a physician using radiological imaging and determining the infectious agent that caused the disease. However, because such diagnosis requires a lot of resources, it is in many cases not done. This is why research literature uses the terms 'clinical pneumonia' or 'WHO-pneumonia' to diagnoses based on _symptoms_ (most importantly, fast breathing and coughing). A symptoms-based definition inevitably means that diseases with similar symptoms may be counted as cases of pneumonia. As a consequence the terms pneumonia and lower respiratory infections (LRIs) are often used interchangeably. The _Institute for Health Metrics and Evaluation _(IHME), for example, provides mortality data on LRIs, in which they include pneumonia caused by a range of different pathogens, but they also include bronchiolitis, a lower respiratory tract infection that mostly affects very young children, in this category.{ref}Institute for Health Metrics and Evaluation (IMHE). (2014). [Pushing the Pace: Progress and Challenges in Fighting Childhood Pneumonia.](http://www.healthdata.org/sites/default/files/files/policy_report/2014/PolicyReport_IHME_PushingthePace_2014.pdf){/ref} {ref}McAllister, D. A., Liu, L., Shi, T., Chu, Y., Reed, C., Burrows, J., ... & Nair, H. (2019). [Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic analysis.](https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf)_The Lancet Global Health_, _7_(1), e47-e57.{/ref} While cases of bronchiolitis are quite common they are generally not fatal, therefore, it is reasonable to assume that the bulk of IHME estimates for the number of deaths from lower respiratory diseases do refer to deaths from pneumonia. --- # Burden of pneumonia --- ## Number of people dying from pneumonia by age In the visualization here we see the global number of deaths from pneumonia{ref}We use the term pneumonia here as a broad term for lower respiratory infections, see [this section](#estimates-that-refer-to-pneumonia-might-also-include-cases-of-other-lower-respiratory-diseases) for how these terms are defined and why they are grouped together.{/ref} by age group. 15% of all [child deaths](https://owid.cloud/child-mortality) in 2017 were caused by pneumonia and it is therefore the leading cause of death of children (see our discussion [here](https://ourworldindata.org/child-mortality#what-are-children-dying-from)). The number of children dying from pneumonia has decreased substantially over the past three decades. In 1990, more than two million children died from pneumonia every year. By 2017, this number had fallen by almost two-thirds. Improvements in the major risk factors such as [childhood wasting](https://ourworldindata.org/hunger-and-undernourishment#too-little-weight-for-height-wasting), [air pollution](https://ourworldindata.org/air-pollution), and [poor sanitation](https://ourworldindata.org/grapher/death-rate-from-unsafe-sanitation), falling [global poverty](https://owid.cloud/extreme-poverty), and a better availability of health technology such as pneumococcal vaccines and antibiotics have all contributed to this decline. While the death _rate_ for old people fell slightly, the _number_ of deaths of people who are 70 years and older increased. [1.13 million](https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths), who died from pneumonia where in this age group. This is because the number of people who reached the age of 70 increased very strongly globally as we show in [our entry](https://owid.cloud/age-structure) on the changing global age structure. <Chart url="https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths"/> ## Pneumonia mortality rates by age The chart shows the annual number of deaths from pneumonia per 100,000 people in different age groups. Looking at the age-group of under 5 year olds we see that there has been a 3-fold reduction in child mortality due to pneumonia over the last three decades. 363 children out of every 100,000 died due to pneumonia in 1990, until 2017 that number has fallen to 119. The mortality rates among other age groups have remained largely the same. The highest pneumonia mortality rates in 2017 were among people aged 70 and older. 261 out of 100,000 people died in this age group due to pneumonia. That's a 9% decrease in mortality rates over the past 3 decades.{ref}(286.1-260.9)/286.1=0.09{/ref} <Chart url="https://ourworldindata.org/grapher/pneumonia-mortality-by-age"/> --- # Where do people die from pneumonia? --- ## Pneumonia death rates – all ages In the map we see the death rate from pneumonia expressed as the number of deaths due to pneumonia per year per 100,000 individuals. We can see that the death rate from pneumonia is highest in Sub-Saharan Africa and Southeast-Asia. The difference between richer and poorer countries is large: European populations suffer a rate of around 10 deaths per 100,000 while poorer countries see rate of more than 100 deaths per 100,000 is In Southeast-Asia, the population of the Philippines suffer from particularly high pneumonia mortality rates; pneumonia is the second leading cause of death in both under-5-year-old and [older than 70](https://ourworldindata.org/grapher/pneumonia-death-rates-70)-year-old populations in this country. These rates have been age-standardized, which tells us the death rate for each country and each point in time as if the age structure of a population. This therefore allows us to make across comparisons across countries and through time that are not affected by differences in the age-structure between countries and changes of the age-structure over time. <Chart url="https://ourworldindata.org/grapher/pneumonia-death-rates-70"/> ## Where do children die from pneumonia The map shows the number of child deaths due to pneumonia per 100,000 children per year. It shows that children are most likely to die from pneumonia across Sub-Saharan Africa and South Asia. The deaths in just [5 countries](https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5) — India, Nigeria, Pakistan, the Democratic Republic of Congo, and Ethiopia – accounted for more than half of all deaths from childhood pneumonia in 2019. For this reason Kevin Watkins and Devi Sridhar called pneumonia _“the ultimate disease of poverty”_ in a 2018 comment in the journal _The Lancet_.{ref}Watkins, K., & Sridhar, D. (2018). [Pneumonia: a global cause without champions.](https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31666-0/fulltext)_ The Lancet_, _392_(10149), 718-719.{/ref} There is a very strong correlation between a country’s income and the child mortality rate from pneumonia as the scatter plot shows. Pneumonia is not a disease that easily spreads across borders, its transmission is generally restricted to local communities and it can be controlled if basic health measures are available. The disease is therefore most common in poor places where healthcare infrastructure is lacking and people are least able to afford the treatment.{ref}The Lancet Global Health Editorial (2018). [The disgraceful neglect of childhood pneumonia.](https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30495-9/fulltext)_ The Lancet. Global health_, _6_(12), e1253.{/ref} <Chart url="https://ourworldindata.org/grapher/pneumonia-death-rates-in-children-under-5"/> <Chart url="https://ourworldindata.org/grapher/death-rates-from-pneumonia-and-other-lower-respiratory-infections-vs-gdp-per-capita?xScale=linear&yScale=linear"/> --- # What are the biggest risks for developing pneumonia? --- ## Why are children dying from pneumonia? To understand how we can reduce the number of children dying from pneumonia we need to understand both prevention and treatment. In the chart we show the number of child deaths from pneumonia which are attributed to various risk factors. ### Undernutrition is the major contributor to pneumonia mortality Here we see that childhood undernutrition, especially so called ‘[child wasting](https://ourworldindata.org/grapher/share-of-children-with-a-weight-too-low-for-their-height-wasting)’ (children who have a weight too low for their height), is the biggest risk factor for pneumonia in children.{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} It contributed to 53% of pneumonia deaths in 2017. Without sufficient energy intake the body cannot cope with increased energy demands required to fight off the infection. A literature review of pneumonia in malnourished children by Mohammod Jobayer Chisti and colleagues found that undernourished children are between two and four times more likely to be admitted to hospital due to pneumonia and up to 15 times more likely to die from it.{ref}Chisti, M. J., Tebruegge, M., La Vincente, S., Graham, S. M., & Duke, T. (2009). [Pneumonia in severely malnourished children in developing countries–mortality risk, aetiology and validity of WHO clinical signs: a systematic review.](https://www.ncbi.nlm.nih.gov/pubmed/19772545?dopt=Abstract)_Tropical medicine & international health_, _14_(10), 1173-1189.{/ref} ### Air pollution and second-hand smoke increase the risk of getting pneumonia [Indoor air pollution](https://owid.cloud/indoor-air-pollution) was the risk factor that is estimated to have lead to 29% of pneumonia deaths in 2017. [Outdoor air pollution](https://owid.cloud/outdoor-air-pollution) was responsible for another 18% of all deaths. Studies have shown that high indoor air pollution in households can double the chances a child develops pneumonia and makes recovery less successful.{ref}Dherani, M., Pope, D., Mascarenhas, M., Smith, K. R., Weber, M., & Bruce, N. (2008). [Indoor air pollution from unprocessed solid fuel use and pneumonia risk in children aged under five years: a systematic review and meta-analysis.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2647443/) _Bulletin of the World Health Organization_ (2006). [Air quality guidelines: global update 2005.](http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf) p123-124.{/ref} One of the underlying reasons for why this is the case is that the [small polluting particles](https://ourworldindata.org/air-pollution#exposure-to-particulate-matter) impair the immune system’s ability to fight and clear the infection. Laura Jones et _al. _(2011) reviewed studies which assessed the impact of secondhand smoke on children, and concluded that children who live in households with smoking parents are more likely to acquire pneumonia as well as other respiratory illnesses. A Global Burden of Disease study by Mattias Öberg et _al._ has estimated that in 2004, globally around 40% of children lived in households where at least one close relative smoked.{ref}Nel, A. (2005). [Air pollution-related illness: effects of particles](https://science.sciencemag.org/content/308/5723/804). _Science_, _308_(5723), 804-806. Öberg, M., Jaakkola, M. S., Woodward, A., Peruga, A., & Prüss-Ustün, A. (2011). [Worldwide burden of disease from exposure to second-hand smoke: a retrospective analysis of data from 192 countries](https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61388-8/fulltext)_. The Lancet_, _377_(9760), 139-146. The study suggested that exposure to secondhand smoke led to 165,000 deaths among children under 5 from lower respiratory diseases that year. {/ref} The data shown here suggests that the exposure to secondhand smoke led to 61,000 deaths among children under 5 from lower respiratory diseases in 2017. ### The risk of pneumonia is higher for children with HIV Exposure to other pathogens such as [measles](https://ourworldindata.org/vaccination#measles-global-vaccination-coverage-and-decline-of-measles) and [HIV](https://ourworldindata.org/hiv-aids) also increases the risk of pneumonia in children. When children who are infected with HIV develop AIDS – which weakens their immune system – their chances of dying from pneumonia increase significantly. A study by Evropi Theodoratou et _al., _published in _Lancet Infectious Diseases,_ found that children with HIV have a seven times greater risk of dying from pneumonia compared to those without it.{ref}Theodoratou, E., McAllister, D. A., Reed, C., Adeloye, D. O., Rudan, I., Muhe, L. M., … & Nair, H. (2014). [Global, regional, and national estimates of pneumonia burden in HIV-infected children in 2010: a meta-analysis and modelling study.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4242006/)_ The Lancet Infectious Diseases_, _14_(12), 1250-1258.{/ref} The same study also showed that the proportion of child deaths from pneumonia that can be attributed to HIV varies widely between countries: in 2010 only 1% of all child deaths from pneumonia in India could be directly attributed to HIV, compared to 64% in Eswatini and 62% in Lesotho. In Africa, a total of 3% of cases and 17% of all childhood deaths from pneumonia was attributable to HIV. These regional differences are important to know so that interventions that can save most lives can be prioritized. ### Overcrowding facilitates pneumonia transmission Pneumonia is not an easily transmittable disease, it requires close contact for the pathogens to be transmitted to another person via air droplets. Therefore overcrowding – too many people living in one space – also increases the risks of pneumonia. This is yet another reason why pneumonia is a disease of poverty: in 2015, 47% of children in low and middle-income countries were living in overcrowded households.{ref}Supplement to: McAllister DA, Liu L, Shi T, et al. [Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic analysis. ](https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf)Lancet Glob Health 2018; published online Nov 26.{/ref} Despite progress against it, more than 800,000 children still die from pneumonia each year. We know where children are dying, and the factors that make them vulnerable to the disease. The key question is how we continue to make progress against it. <Chart url="https://ourworldindata.org/grapher/pneumonia-risk-factors?time=latest"/> ## Pneumonia risk factors for people aged 70 and older The risk factors for developing pneumonia in people aged 70 and older are similar to the risk factors that lead to pneumonia in children. [Outdoor air pollution](https://owid.cloud/outdoor-air-pollution) – small particulate matter air pollution – is the risk factor that lead to most deaths. In 2017 it lead to more than 300,000 deaths from pneumonia of older people. Smoking and exposure to secondhand smoke have contributed to 150,000 and 73,000 deaths from pneumonia in this age group, respectively. <Chart url="https://ourworldindata.org/grapher/deaths-from-pneumonia-in-people-aged-70-and-older-by-risk-factor?time=latest"/> --- # How can we reduce the number of people dying from pneumonia? --- When we understand what risks can lead to pneumonia, we can find ways to reduce them. Furthermore, because a number of risks factors for pneumonia overlap with risk factors for other diseases, [especially diarrheal diseases](https://ourworldindata.org/childhood-diarrheal-diseases), interventions that target pneumonia have the additional benefit of helping to limit other diseases and saving more lives. ### Vaccines against pneumonia There are several versions of [pneumococcal conjugate vaccine](https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine) (PCV), which target different serotypes of _S. pneumoniae _— the bacterium responsible for most cases of pneumonia. The PCV vaccine is given to children younger than 24 months. According to a study by Cheryl Cohen et _al._ (2017), PVC13 – the currently recommended PCV vaccine version – has 85% effectiveness against invasive infections caused by the specific pneumococcal strains_ _included in the vaccine formulation.{ref}Cohen, C., Von Mollendorf, C., De Gouveia, L., Lengana, S., Meiring, S., Quan, V., ... & Madhi, S. A. (2017). [Effectiveness of the 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in South African children: a case-control study. ](https://www.ncbi.nlm.nih.gov/pubmed/28139443/)_The Lancet Global Health_, _5_(3), e359-e369. 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). Moore, M. R., Link-Gelles, R., Schaffner, W., Lynfield, R., Holtzman, C., Harrison, L. H., ... & Thomas, A. (2016). [Effectiveness of 13-valent pneumococcal conjugate vaccine for prevention of invasive pneumococcal disease in children in the USA: a matched case-control study.](https://www.sciencedirect.com/science/article/abs/pii/S2213260016000527?via%3Dihub)_The Lancet Respiratory Medicine_, _4_(5), 399-406.{/ref} It has been estimated that if PCV13 coverage in low income countries would reach the coverage of the [DTP3 vaccine](https://ourworldindata.org/grapher/share-of-children-immunized-dtp3), then PCV13 could prevent 399,000 child deaths and 54.6 million pneumonia episodes annually when compared with a world in which no pneumococcal vaccination was available.{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} India – which has the highest number of child deaths from pneumonia – only introduced PCV13 in 2017 and the [coverage is still very low](https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine?tab=chart) — clearly the pneumococcal vaccine still has a lot of potential.{ref}Read more about pneumococcal vaccines in the [section below.](#pneumococcal-vaccines) In addition, vaccinating children with PCV can protect adults via [herd effect](https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity-and-reasons-for-caring-about-broad-vaccination-coverage), which means that benefits are not limited to one age group the population — especially important because pneumonia has a [significant burden in older people](https://docs.google.com/document/d/1IDDdkIyv1oTf-cY444pShF6AxsDRoBYhzUxTSR7sZHw/edit#bookmark=id.j87y55283i1n). 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} Another vaccine widely used to protect children against both pneumonia is the [Hib vaccine](https://ourworldindata.org/grapher/hib-vaccine). Hib immunizes children against _Haemophilus influenzae_ type b, a leading cause of meningitis in children that is also responsible for around 2% of pneumonia deaths of children younger than five years. In 2015 there were around 0.9 million cases of Hib-related pneumonia globally. The Hib immunization provides around 70% protection against Hib-related pneumonia and 84% protection against meningitis in children.{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} ### Promoting breastfeeding Encouraging mothers to breastfeed during the first 6 months of a child’s life has a positive impact on reducing child undernutrition, which in turn protects from infectious diseases such as pneumonia. According to Laura Lamberti et _al. _(2013), pneumonia mortality of children in developing countries who are not breastfed in the first 5 months of their lives is 15 times greater than those who exclusively received their mother’s milk.{ref}Lamberti, L. M., Zakarija-Grković, I., Walker, C. L. F., Theodoratou, E., Nair, H., Campbell, H., & Black, R. E. (2013). [Breastfeeding for reducing the risk of pneumonia morbidity and mortality in children under two: a systematic literature review and meta-analysis.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3847465/)_ BMC public health_, _13_(3), S18.{/ref} As the map shows, the number of infants who are exclusively breast fed is still low in many countries. Globally, an estimated 41% of infants were exclusively breastfed in 2017.{ref}41% number is estimated by the UNICEF based on the most recent data available for the countries from surveys between 2013-2018. UNICEF DATA. (2019). [_Infant and young child feeding_.](https://data.unicef.org/topic/nutrition/infant-and-young-child-feeding/) [online][Accessed 4 Sep. 2019].{/ref} <Chart url="https://ourworldindata.org/grapher/exclusive-breastfeeding"/> ### Reducing air pollution There has been significant progress in reducing [air pollution](https://owid.cloud/air-pollution) levels in recent decades, particularly of [indoor air pollution](https://owid.cloud/indoor-air-pollution). Death rates from indoor air pollution [fell](https://ourworldindata.org/grapher/death-rate-by-source-from-indoor-air-pollution) as a result of [improved access](https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking?tab=chart&time=2000..2016&country=OWID_WRL) to cleaner fuels for heating and cooking. But there is still much progress to be made, especially in Sub-Saharan Africa, where in most countries [less than 10% of households](https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking) have access to clean fuels for cooking. And, whilst progress has been made against indoor air pollution, high levels of [outdoor pollution](https://ourworldindata.org/grapher/pm25-air-pollution) remain a problem across many countries. Reducing air pollution levels would have many other benefits: it would not only reduce the number of cases of pneumonia but also limit the incidence of asthma in children for example.{ref} WHO, U. (2006). [Air quality guidelines: global update 2005.](http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf) p123-124. _World Health Organization_. {/ref} ### Access to healthcare and treatment A child with a suspected case of pneumonia – with symptoms of difficulty in breathing and coughing – should be taken to a healthcare provider so that the correct and immediate treatment can be provided. Delay in seeking treatment can increase the chances of a child dying.{ref}Ferdous, F., Ahmed, S., Das, S. K., Chisti, M. J., Nasrin, D., Kotloff, K. L., ... & Wagatsuma, Y. (2018). [Pneumonia mortality and healthcare utilization in young children in rural Bangladesh: a prospective verbal autopsy study.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5970515/)_Tropical medicine and health_, _46_(1), 17.{/ref} However, as the map shows, seeking healthcare is still not as common as it should be. Globally, less than two-thirds of children with symptoms of pneumonia were taken to a healthcare provider in 2016. This figure is even lower in places where healthcare is most needed — just 47% in Sub-Saharan Africa.{ref} UNICEF DATA. (2018). [_Pneumonia in Children_.](https://data.unicef.org/topic/child-health/pneumonia/) [online] [Accessed 5 Sep. 2019]{/ref} As the map shows, the share of children with symptoms of pneumonia that are taken to a health provider is still low in many countries. <Chart url="https://ourworldindata.org/grapher/pneumonia-careseeking"/> ### Access to antibiotic treatment Given that most cases of pneumonia are of bacterial origin, antibiotics are the general course of treatment. Due to the lack of resources, in places where pneumonia cases are most common, a quick diagnosis for the cause of disease is not always possible. Given the potential high risk of death from untreated pneumonia, the World Health Organisation (WHO) recommends antibiotic treatment depending on the disease symptoms and its severity before the cause of disease is known. Amoxicillin, ampicillin and gentamicin are the most commonly used antibiotics to treat pneumonia.{ref} World Health Organization. (2014). [_Revised WHO classification and treatment of pneumonia in children at health facilities: quick reference guide_](https://apps.who.int/iris/bitstream/handle/10665/137319/9789241507813_eng.pdf?sequence=1) (No. WHO/FWC/MCA/14.9). World Health Organization.{/ref} Antibiotics are a relatively cheap and effective treatment, a course of amoxicillin costs less than 50 cents. {ref}Unicef.org. (2018). [_Amoxicillin Dispersible Tablets: Market and Supply Update_.](https://www.unicef.org/supply/files/Amoxicillin_DT_Supply_Update.pdf) [online] [Accessed 26 Sep. 2019]. {/ref} {ref}Unicef. (2016). [The State of the World's Children 2016](https://www.unicef.org/publications/files/UNICEF_SOWC_2016.pdf). _New York: United Nations Children’s Fund_.{/ref} ### Oxygen therapy During pneumonia, alveoli in the lungs get filled with pus and fluid, which prevents oxygen from being transferred to the blood. Consequently, a condition known as hypoxaemia – a lack of oxygen – can develop. When a child with pneumonia develops hypoxaemia the risk of dying increases five-fold.{ref}Lazzerini, M., Sonego, M., & Pellegrin, M. C. (2015). [Hypoxaemia as a mortality risk factor in acute lower respiratory infections in children in low and middle-income countries: systematic review and meta-analysis. ](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4570717/)_PLoS One_, _10_(9), e0136166.{/ref} Treatment with oxygen therapy (supplying oxygen-enriched air to the patient){ref}The air we breathe contains 21% of oxygen gas, but it is possible to concentrate this gas using special oxygen concentrators. The oxygen-enriched air can then be supplied to a person with pneumonia via a breathing mask, in this way compensating for reduced oxygen exchange in the lungs.{/ref} is one way to mitigate hypoxaemia.{ref}World Health Organization. (2016). [Oxygen therapy for children: a manual for health workers.](https://www.who.int/maternal_child_adolescent/documents/child-oxygen-therapy/en/) {/ref} A study from Papua New Guinea has shown that oxygen therapy can reduce the risk of death from severe pneumonia by 35%. However, the need for a specialist equipment to diagnose and treat hypoxaemia still poses a substantial barrier in low-resource settings. Since 2017, the WHO includes oxygen in its List of Essential Medicines.{ref} World Health Organization. (2019). [WHO model list of essential medicines: 7th list](https://www.who.int/medicines/publications/essentialmedicines/en/), August 2019. {/ref} Improved access to oxygen could save the lives of 120,000 children annually.{ref}Delarosa, J., Hayes, J., Pantjushenko, E., Keith, B., Ambler, G. and Lawrence, C. (2017). [_Oxygen Is Essential: A Policy and Advocacy Primer_](https://path.azureedge.net/media/documents/DRG_Oxygen_Primer.pdf). [online] PATH. [Accessed 5 Sep. 2019].{/ref} --- # 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} --- # Additional Information --- ## What pathogens cause pneumonia? Pneumonia is an infection of the lower respiratory tract that can be caused by multiple microbial pathogens. By far the most common cause of pneumonia in unvaccinated children is an infection by a bacterium called _Streptococcus pneumoniae_, simply referred to as pneumococcus. The Global Burden of Disease (GBD) study from 2018 has estimated that pneumococcus_ _was responsible for 52% of 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} Other pathogens which cause pneumonia in children are _Haemophilus influenzae_ type b, respiratory syncytial virus (RSV), and the influenza virus. Each of these pathogens was responsible for less than 4% of lethal pneumonia cases 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} Despite being minor causes, it’s important to continue developing treatments against these pathogens; they will become increasingly important as vaccination coverage for the most common causes increases. According to a study by Katherine O'Brien et _al._ (2019), when children are routinely vaccinated with pneumococcal and Hib vaccines, as many as 62% of pneumonia cases are caused by viral pathogens such as RSV.{ref}O'Brien, K. L., Baggett, H. C., Brooks, W. A., Feikin, D. R., Hammitt, L. L., Higdon, M. M., ... & Madhi, S. A. (2019). [Causes of severe pneumonia requiring hospital admission in children without HIV infection from Africa and Asia: the PERCH multi-country case-control study.](https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)30721-4/fulltext)_ The Lancet_. {/ref} ## How is pneumonia acquired and transmitted? Children can contract pneumonia in a number of ways. Pneumococcus and _H. influenzae _are bacteria that can be found in the upper respiratory tract of healthy individuals without any symptoms. Under circumstances when the conditions in the upper respiratory tract are compromised{ref}For example, when a secondary infection with a virus occurs, which may trigger multiplication of usually non-pathogenic bacteria.{/ref} these normally benign bacteria may move to the lower respiratory tract where they lead to pneumonia.{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} Pneumonia caused by bacterial and viral pathogens can be contagious and transmitted when a person coughs or sneezes. However, precautions such as sanitizing hands and surfaces, wearing a face mask if available and limiting close contact with a sick person can significantly limit the chances of transmission. | { "id": 26939, "date": "2018-11-04T12:09:26", "guid": { "rendered": "https://owid.cloud/?page_id=26939" }, "link": "https://owid.cloud/pneumonia", "meta": { "owid_publication_context_meta_field": [], "owid_key_performance_indicators_meta_field": { "raw": "**2.5 million** people die from pneumonia every year. \n\nOne-fourth are children younger than five years old.", "rendered": "<p><strong>2.5 million</strong> people die from pneumonia every year.</p>\n<p>One-fourth are children younger than five years old.</p>\n" } }, "slug": "pneumonia", "tags": [], "type": "page", "title": { "rendered": "Pneumonia" }, "_links": { "self": [ { "href": "https://owid.cloud/wp-json/wp/v2/pages/26939" } ], "about": [ { "href": "https://owid.cloud/wp-json/wp/v2/types/page" } ], "author": [ { "href": "https://owid.cloud/wp-json/wp/v2/users/33", "embeddable": true } ], "curies": [ { "href": "https://api.w.org/{rel}", "name": "wp", "templated": true } ], "replies": [ { "href": "https://owid.cloud/wp-json/wp/v2/comments?post=26939", "embeddable": true } ], "wp:term": [ { "href": "https://owid.cloud/wp-json/wp/v2/categories?post=26939", "taxonomy": "category", "embeddable": true }, { "href": "https://owid.cloud/wp-json/wp/v2/tags?post=26939", "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=26939" } ], "version-history": [ { "href": "https://owid.cloud/wp-json/wp/v2/pages/26939/revisions", "count": 30 } ], "wp:featuredmedia": [ { "href": "https://owid.cloud/wp-json/wp/v2/media/42330", "embeddable": true } ], "predecessor-version": [ { "id": 49849, "href": "https://owid.cloud/wp-json/wp/v2/pages/26939/revisions/49849" } ] }, "author": 33, "parent": 0, "status": "publish", "content": { "rendered": "\n<div class=\"blog-info\">This entry was first published in November 2019.</div>\n\n\n\n<p>2.5 million people died from pneumonia in 2019. Almost a third of all victims were children younger than 5 years, it is the leading cause of death for children under 5.</p>\n\n\n\n<p>Pneumonia is an infection of the tiny air sacs of the lungs, called alveoli. In a person with pneumonia the alveoli are filled with pus and fluid, which makes breathing painful and reduces the oxygen intake. Pneumonia is caused by a number of different infectious agents, including viruses, bacteria and fungi.</p>\n\n\n\n<p>Here in this research entry we look at who is suffering from pneumonia and why \u2013 and what can we do to reduce the number of people dying from this disease. </p>\n\n\n\t<div class=\"wp-block-owid-summary\">\n\t\t<h2>Summary</h2>\n\t\t\n\n<ul><li><a href=\"#burden-of-pneumonia\">Pneumonia is the leading cause of death for children under 5 \u2014 more than 800,000 children died due to pneumonia in 2017.</a></li><li><a href=\"#burden-of-pneumonia\">While still too many children die today, since 1990 we\u2019ve seen more than 3-fold reduction in child mortality rates from pneumonia globally.</a></li><li><a href=\"#pneumonia-mortality-rates-by-age\">The global mortality rates for older people remained unchanged since 1990.</a></li><li><a href=\"#where-do-children-die-from-pneumonia\">Mortality from pneumonia is highest in Sub-Saharan Africa.</a></li><li><a href=\"#what-are-the-biggest-risks-for-developing-pneumonia\">The greatest risk factors for developing pneumonia are undernutrition, air pollution and smoking.</a></li><li><a href=\"#how-can-we-reduce-the-number-of-people-dying-from-pneumonia\">Reducing exposure to risk factors and higher coverage of pneumococcal vaccines can reduce the number deaths from pneumonia.</a></li><li><a href=\"#pneumococcal-vaccines\">Research suggests that pneumococcal vaccines could be saving the lives of almost 400,000 children annually.</a></li></ul>\n\n\n\t</div>\n\n\n<p> </p>\n\n\n\n<h4>Estimates that refer to pneumonia might also include cases of other lower respiratory diseases</h4>\n\n\n\n<p>Ideally, pneumonia would always be diagnosed by a physician using radiological imaging and determining the infectious agent that caused the disease. However, because such diagnosis requires a lot of resources, it is in many cases not done.</p>\n\n\n\n<p>This is why research literature uses the terms ‘clinical pneumonia’ or ‘WHO-pneumonia’ to diagnoses based on <em>symptoms</em> (most importantly, fast breathing and coughing). A symptoms-based definition inevitably means that diseases with similar symptoms may be counted as cases of pneumonia.</p>\n\n\n\n<p>As a consequence the terms pneumonia and lower respiratory infections (LRIs) are often used interchangeably. The <em>Institute for Health Metrics and Evaluation </em>(IHME), for example, provides mortality data on LRIs, in which they include pneumonia caused by a range of different pathogens, but they also include bronchiolitis, a lower respiratory tract infection that mostly affects very young children, in this category.{ref}Institute for Health Metrics and Evaluation (IMHE). (2014). <a href=\"http://www.healthdata.org/sites/default/files/files/policy_report/2014/PolicyReport_IHME_PushingthePace_2014.pdf\">Pushing the Pace: Progress and Challenges in Fighting Childhood Pneumonia.</a>{/ref} {ref}McAllister, D. A., Liu, L., Shi, T., Chu, Y., Reed, C., Burrows, J., … & Nair, H. (2019). <a href=\"https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf\">Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic analysis.</a> <em>The Lancet Global Health</em>, <em>7</em>(1), e47-e57.{/ref} While cases of bronchiolitis are quite common they are generally not fatal, therefore, it is reasonable to assume that the bulk of IHME estimates for the number of deaths from lower respiratory diseases do refer to deaths from pneumonia.\u00a0</p>\n\n\n\n<h2>Burden of pneumonia</h2>\n\n\n\n<h3>Number of people dying from pneumonia by age</h3>\n\n\n\n<p>In the visualization here we see the global number of deaths from pneumonia{ref}We use the term pneumonia here as a broad term for lower respiratory infections, see <a href=\"#estimates-that-refer-to-pneumonia-might-also-include-cases-of-other-lower-respiratory-diseases\">this section</a> for how these terms are defined and why they are grouped together.{/ref} by age group.</p>\n\n\n\n<p>15% of all <a href=\"https://owid.cloud/child-mortality\">child deaths</a> in 2017 were caused by pneumonia and it is therefore the leading cause of death of children (see our discussion <a href=\"https://ourworldindata.org/child-mortality#what-are-children-dying-from\">here</a>).</p>\n\n\n\n<p>The number of children dying from pneumonia has decreased substantially over the past three decades. In 1990, more than two million children died from pneumonia every year. By 2017, this number had fallen by almost two-thirds. </p>\n\n\n\n<p>Improvements in the major risk factors such as <a href=\"https://ourworldindata.org/hunger-and-undernourishment#too-little-weight-for-height-wasting\">childhood wasting</a>, <a href=\"https://ourworldindata.org/air-pollution\">air pollution</a>, and <a href=\"https://ourworldindata.org/grapher/death-rate-from-unsafe-sanitation\">poor sanitation</a>, falling <a href=\"https://owid.cloud/extreme-poverty\">global poverty</a>, and a better availability of health technology such as pneumococcal vaccines and antibiotics have all contributed to this decline.</p>\n\n\n\n<p>While the death <em>rate</em> for old people fell slightly, the <em>number</em> of deaths of people who are 70 years and older increased. <a href=\"https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths\">1.13 million</a>, who died from pneumonia where in this age group. This is because the number of people who reached the age of 70 increased very strongly globally as we show in <a href=\"https://owid.cloud/age-structure\">our entry</a> on the changing global age structure. </p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/pneumonia-and-lower-respiratory-diseases-deaths\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>Pneumonia mortality rates by age</h3>\n\n\n\n<p>The chart shows the annual number of deaths from pneumonia per 100,000 people in different age groups.</p>\n\n\n\n<p>Looking at the age-group of under 5 year olds we see that there has been a 3-fold reduction in child mortality due to pneumonia over the last three decades. 363 children out of every 100,000 died due to pneumonia in 1990, until 2017 that number has fallen to 119.</p>\n\n\n\n<p>The mortality rates among other age groups have remained largely the same. The highest pneumonia mortality rates in 2017 were among people aged 70 and older. 261 out of 100,000 people died in this age group due to pneumonia. That’s a 9% decrease in mortality rates over the past 3 decades.{ref}(286.1-260.9)/286.1=0.09{/ref} </p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/pneumonia-mortality-by-age\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h2>Where do people die from pneumonia?</h2>\n\n\n\n<h3>Pneumonia death rates \u2013 all ages</h3>\n\n\n\n<p>In the map we see the death rate from pneumonia expressed as the number of deaths due to pneumonia per year per 100,000 individuals. </p>\n\n\n\n<p>We can see that the death rate from pneumonia is highest in Sub-Saharan Africa and Southeast-Asia. The difference between richer and poorer countries is large: European populations suffer a rate of around 10 deaths per 100,000 while poorer countries see rate of more than 100 deaths per 100,000 is </p>\n\n\n\n<p>In Southeast-Asia, the population of the Philippines suffer from particularly high pneumonia mortality rates; pneumonia is the second leading cause of death in both under-5-year-old and <a href=\"https://ourworldindata.org/grapher/pneumonia-death-rates-70\">older than 70</a>-year-old populations in this country. </p>\n\n\n\n<p>These rates have been age-standardized, which tells us the death rate for each country and each point in time as if the age structure of a population. This therefore allows us to make across comparisons across countries and through time that are not affected by differences in the age-structure between countries and changes of the age-structure over time.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/pneumonia-death-rates-70\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h3>Where do children die from pneumonia</h3>\n\n\n\n<p>The map shows the number of child deaths due to pneumonia per 100,000 children per year.</p>\n\n\n\n<p>It shows that children are most likely to die from pneumonia across Sub-Saharan Africa and South Asia. The deaths in just <a href=\"https://ourworldindata.org/grapher/number-of-deaths-from-pneumonia-in-children-under-5\">5 countries</a> \u2014 India, Nigeria, Pakistan, the Democratic Republic of Congo, and Ethiopia \u2013 accounted for more than half of all deaths from childhood pneumonia in 2019.\u00a0</p>\n\n\n\n<p>For this reason Kevin Watkins and Devi Sridhar called pneumonia <em>\u201cthe ultimate disease of poverty\u201d</em> in a 2018 comment in the journal <em>The Lancet</em>.{ref}Watkins, K., & Sridhar, D. (2018). <a href=\"https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31666-0/fulltext\">Pneumonia: a global cause without champions.</a><em> The Lancet</em>, <em>392</em>(10149), 718-719.{/ref} There is a very strong correlation between a country\u2019s income and the child mortality rate from pneumonia as the scatter plot shows.</p>\n\n\n\n<p>Pneumonia is not a disease that easily spreads across borders, its transmission is generally restricted to local communities and it can be controlled if basic health measures are available. The disease is therefore most common in poor places where healthcare infrastructure is lacking and people are least able to afford the treatment.{ref}The Lancet Global Health Editorial (2018). <a href=\"https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30495-9/fulltext\">The disgraceful neglect of childhood pneumonia.</a><em> The Lancet. Global health</em>, <em>6</em>(12), e1253.{/ref} </p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/pneumonia-death-rates-in-children-under-5\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/death-rates-from-pneumonia-and-other-lower-respiratory-infections-vs-gdp-per-capita?xScale=linear&yScale=linear\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h2>What are the biggest risks for developing pneumonia?</h2>\n\n\n\n<h3>Why are children dying from pneumonia?</h3>\n\n\n\n<div class=\"wp-block-columns is-style-sticky-right\">\n<div class=\"wp-block-column\">\n<p>To understand how we can reduce the number of children dying from pneumonia we need to understand both prevention and treatment. </p>\n\n\n\n<p>In the chart we show the number of child deaths from pneumonia which are attributed to various risk factors. </p>\n\n\n\n<h4>Undernutrition is the major contributor to pneumonia mortality</h4>\n\n\n\n<p>Here we see that childhood undernutrition, especially so called \u2018<a href=\"https://ourworldindata.org/grapher/share-of-children-with-a-weight-too-low-for-their-height-wasting\">child wasting</a>\u2019 (children who have a weight too low for their height), is the biggest risk factor for pneumonia in children.{ref}Troeger, C., Blacker, B., Khalil, I. A., Rao, P. C., Cao, J., Zimsen, S. R., \u2026 & 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} It contributed to 53% of pneumonia deaths in 2017. Without sufficient energy intake the body cannot cope with increased energy demands required to fight off the infection. </p>\n\n\n\n<p>A literature review of pneumonia in malnourished children by Mohammod Jobayer Chisti and colleagues found that undernourished children are between two and four times more likely to be admitted to hospital due to pneumonia and up to 15 times more likely to die from it.{ref}Chisti, M. J., Tebruegge, M., La Vincente, S., Graham, S. M., & Duke, T. (2009). <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/19772545?dopt=Abstract\">Pneumonia in severely malnourished children in developing countries\u2013mortality risk, aetiology and validity of WHO clinical signs: a systematic review.</a> <em>Tropical medicine & international health</em>, <em>14</em>(10), 1173-1189.{/ref}</p>\n\n\n\n<h4>Air pollution and second-hand smoke increase the risk of getting pneumonia </h4>\n\n\n\n<p><a href=\"https://owid.cloud/indoor-air-pollution\">Indoor air pollution</a> was the risk factor that is estimated to have lead to 29% of pneumonia deaths in 2017. <a href=\"https://owid.cloud/outdoor-air-pollution\">Outdoor air pollution</a> was responsible for another 18% of all deaths.</p>\n\n\n\n<p>Studies have shown that high indoor air pollution in households can double the chances a child develops pneumonia and makes recovery less successful.{ref}Dherani, M., Pope, D., Mascarenhas, M., Smith, K. R., Weber, M., & Bruce, N. (2008). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2647443/\">Indoor air pollution from unprocessed solid fuel use and pneumonia risk in children aged under five years: a systematic review and meta-analysis.</a></p>\n\n\n\n<p><em>Bulletin of the World Health Organization</em> (2006). <a href=\"http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf\">Air quality guidelines: global update 2005.</a> p123-124.{/ref} One of the underlying reasons for why this is the case is that the <a href=\"https://ourworldindata.org/air-pollution#exposure-to-particulate-matter\">small polluting particles</a> impair the immune system\u2019s ability to fight and clear the infection.</p>\n\n\n\n<p>Laura Jones et <em>al. </em>(2011) reviewed studies which assessed the impact of secondhand smoke on children, and concluded that children who live in households with smoking parents are more likely to acquire pneumonia as well as other respiratory illnesses. A Global Burden of Disease study by Mattias \u00d6berg et <em>al.</em> has estimated that in 2004, globally around 40% of children lived in households where at least one close relative smoked.{ref}Nel, A. (2005). <a href=\"https://science.sciencemag.org/content/308/5723/804\">Air pollution-related illness: effects of particles</a>. <em>Science</em>, <em>308</em>(5723), 804-806.</p>\n\n\n\n<p>\u00d6berg, M., Jaakkola, M. S., Woodward, A., Peruga, A., & Pr\u00fcss-Ust\u00fcn, A. (2011). <a href=\"https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61388-8/fulltext\">Worldwide burden of disease from exposure to second-hand smoke: a retrospective analysis of data from 192 countries</a><em>. The Lancet</em>, <em>377</em>(9760), 139-146. The study suggested that exposure to secondhand smoke led to 165,000 deaths among children under 5 from lower respiratory diseases that year.<br>{/ref} The data shown here suggests that the exposure to secondhand smoke led to 61,000 deaths among children under 5 from lower respiratory diseases in 2017.</p>\n\n\n\n<h4>The risk of pneumonia is higher for children with HIV</h4>\n\n\n\n<p>Exposure to other pathogens such as <a href=\"https://ourworldindata.org/vaccination#measles-global-vaccination-coverage-and-decline-of-measles\">measles</a> and <a href=\"https://ourworldindata.org/hiv-aids\">HIV</a> also increases the risk of pneumonia in children. </p>\n\n\n\n<p>When children who are infected with HIV develop AIDS \u2013 which weakens their immune system \u2013 their chances of dying from pneumonia increase significantly. A study by Evropi Theodoratou et <em>al., </em>published in <em>Lancet Infectious Diseases,</em> found that children with HIV have a seven times greater risk of dying from pneumonia compared to those without it.{ref}Theodoratou, E., McAllister, D. A., Reed, C., Adeloye, D. O., Rudan, I., Muhe, L. M., \u2026 & Nair, H. (2014). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4242006/\">Global, regional, and national estimates of pneumonia burden in HIV-infected children in 2010: a meta-analysis and modelling study.</a><em> The Lancet Infectious Diseases</em>, <em>14</em>(12), 1250-1258.{/ref}</p>\n\n\n\n<p>The same study also showed that the proportion of child deaths from pneumonia that can be attributed to HIV varies widely between countries: in 2010 only 1% of all child deaths from pneumonia in India could be directly attributed to HIV, compared to 64% in Eswatini and 62% in Lesotho. In Africa, a total of 3% of cases and 17% of all childhood deaths from pneumonia was attributable to HIV. These regional differences are important to know so that interventions that can save most lives can be prioritized. </p>\n\n\n\n<h4>Overcrowding facilitates pneumonia transmission </h4>\n\n\n\n<p>Pneumonia is not an easily transmittable disease, it requires close contact for the pathogens to be transmitted to another person via air droplets. Therefore overcrowding \u2013 too many people living in one space \u2013 also increases the risks of pneumonia. This is yet another reason why pneumonia is a disease of poverty: in 2015, 47% of children in low and middle-income countries were living in overcrowded households.{ref}Supplement to: McAllister DA, Liu L, Shi T, et al. <a href=\"https://www.thelancet.com/cms/10.1016/S2214-109X(18)30408-X/attachment/41ca9e56-e528-4788-bb38-1d4c9f76e6d4/mmc1.pdf\">Global, regional, and national estimates of pneumonia morbidity and mortality in children younger than 5 years between 2000 and 2015: a systematic analysis. </a>Lancet Glob Health 2018; published online Nov 26.{/ref}</p>\n\n\n\n<p>Despite progress against it, more than 800,000 children still die from pneumonia each year. We know where children are dying, and the factors that make them vulnerable to the disease. The key question is how we continue to make progress against it.</p>\n</div>\n\n\n\n<div class=\"wp-block-column\">\n<iframe src=\"https://ourworldindata.org/grapher/pneumonia-risk-factors?time=latest\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n</div>\n</div>\n\n\n\n<h3>Pneumonia risk factors for people aged 70 and older</h3>\n\n\n\n<p>The risk factors for developing pneumonia in people aged 70 and older are similar to the risk factors that lead to pneumonia in children. </p>\n\n\n\n<p><a href=\"https://owid.cloud/outdoor-air-pollution\">Outdoor air pollution</a> \u2013 small particulate matter air pollution \u2013 is the risk factor that lead to most deaths. In 2017 it lead to more than 300,000 deaths from pneumonia of older people. </p>\n\n\n\n<p>Smoking and exposure to secondhand smoke have contributed to 150,000 and 73,000 deaths from pneumonia in this age group, respectively.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/deaths-from-pneumonia-in-people-aged-70-and-older-by-risk-factor?time=latest\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h2>How can we reduce the number of people dying from pneumonia?</h2>\n\n\n\n<p>When we understand what risks can lead to pneumonia, we can find ways to reduce them. Furthermore, because a number of risks factors for pneumonia overlap with risk factors for other diseases, <a href=\"https://ourworldindata.org/childhood-diarrheal-diseases\">especially diarrheal diseases</a>, interventions that target pneumonia have the additional benefit of helping to limit other diseases and saving more lives.</p>\n\n\n\n<h4>Vaccines against pneumonia</h4>\n\n\n\n<p>There are several versions of <a href=\"https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine\">pneumococcal conjugate vaccine</a> (PCV), which target different serotypes of <em>S. pneumoniae </em>\u2014 the bacterium responsible for most cases of pneumonia. </p>\n\n\n\n<p>The PCV vaccine is given to children younger than 24 months. According to a study by Cheryl Cohen et <em>al.</em> (2017), PVC13 \u2013 the currently recommended PCV vaccine version \u2013 has 85% effectiveness against invasive infections caused by the specific pneumococcal strains<em> </em>included in the vaccine formulation.{ref}Cohen, C., Von Mollendorf, C., De Gouveia, L., Lengana, S., Meiring, S., Quan, V., … & Madhi, S. A. (2017). <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/28139443/\">Effectiveness of the 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease in South African children: a case-control study. </a><em>The Lancet Global Health</em>, <em>5</em>(3), e359-e369.<br></p>\n\n\n\n<p>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).<br></p>\n\n\n\n<p>Moore, M. R., Link-Gelles, R., Schaffner, W., Lynfield, R., Holtzman, C., Harrison, L. H., … & Thomas, A. (2016). <a href=\"https://www.sciencedirect.com/science/article/abs/pii/S2213260016000527?via%3Dihub\">Effectiveness of 13-valent pneumococcal conjugate vaccine for prevention of invasive pneumococcal disease in children in the USA: a matched case-control study.</a> <em>The Lancet Respiratory Medicine</em>, <em>4</em>(5), 399-406.{/ref} </p>\n\n\n\n<p>It has been estimated that if PCV13 coverage in low income countries would reach the coverage of the <a href=\"https://ourworldindata.org/grapher/share-of-children-immunized-dtp3\">DTP3 vaccine</a>, then PCV13 could prevent 399,000 child deaths and 54.6 million pneumonia episodes annually when compared with a world in which no pneumococcal vaccination was available.{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} India \u2013 which has the highest number of child deaths from pneumonia \u2013 only introduced PCV13 in 2017 and the <a href=\"https://ourworldindata.org/grapher/share-of-one-year-olds-who-received-the-final-dose-of-pneumococcal-vaccine?tab=chart\">coverage is still very low</a> \u2014 clearly the pneumococcal vaccine still has a lot of potential.{ref}Read more about pneumococcal vaccines in the <a href=\"#pneumococcal-vaccines\">section below.</a></p>\n\n\n\n<p>In addition, vaccinating children with PCV can protect adults via <a href=\"https://ourworldindata.org/vaccination#how-vaccines-work-herd-immunity-and-reasons-for-caring-about-broad-vaccination-coverage\">herd effect</a>, which means that benefits are not limited to one age group the population \u2014 especially important because pneumonia has a <a href=\"https://docs.google.com/document/d/1IDDdkIyv1oTf-cY444pShF6AxsDRoBYhzUxTSR7sZHw/edit#bookmark=id.j87y55283i1n\">significant burden in older people</a>. <br>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}</p>\n\n\n\n<p>Another vaccine widely used to protect children against both pneumonia is the <a href=\"https://ourworldindata.org/grapher/hib-vaccine\">Hib vaccine</a>. </p>\n\n\n\n<p>Hib immunizes children against <em>Haemophilus influenzae</em> type b, a leading cause of meningitis in children that is also responsible for around 2% of pneumonia deaths of children younger than five years. In 2015 there were around 0.9 million cases of Hib-related pneumonia globally. The Hib immunization provides around 70% protection against Hib-related pneumonia and 84% protection against meningitis in children.{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}</p>\n\n\n\n<h4>Promoting breastfeeding</h4>\n\n\n\n<p>Encouraging mothers to breastfeed during the first 6 months of a child\u2019s life has a positive impact on reducing child undernutrition, which in turn protects from infectious diseases such as pneumonia. </p>\n\n\n\n<p>According to Laura Lamberti et <em>al. </em>(2013), pneumonia mortality of children in developing countries who are not breastfed in the first 5 months of their lives is 15 times greater than those who exclusively received their mother\u2019s milk.{ref}Lamberti, L. M., Zakarija-Grkovi\u0107, I., Walker, C. L. F., Theodoratou, E., Nair, H., Campbell, H., & Black, R. E. (2013). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3847465/\">Breastfeeding for reducing the risk of pneumonia morbidity and mortality in children under two: a systematic literature review and meta-analysis.</a><em> BMC public health</em>, <em>13</em>(3), S18.{/ref} As the map shows, the number of infants who are exclusively breast fed is still low in many countries. Globally, an estimated 41% of infants were exclusively breastfed in 2017.{ref}41% number is estimated by the UNICEF based on the most recent data available for the countries from surveys between 2013-2018. <br>UNICEF DATA. (2019). <a href=\"https://data.unicef.org/topic/nutrition/infant-and-young-child-feeding/\"><em>Infant and young child feeding</em>.</a> [online][Accessed 4 Sep. 2019].{/ref}</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/exclusive-breastfeeding\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h4>Reducing air pollution</h4>\n\n\n\n<p>There has been significant progress in reducing <a href=\"https://owid.cloud/air-pollution\">air pollution</a> levels in recent decades, particularly of <a href=\"https://owid.cloud/indoor-air-pollution\">indoor air pollution</a>. </p>\n\n\n\n<p>Death rates from indoor air pollution <a href=\"https://ourworldindata.org/grapher/death-rate-by-source-from-indoor-air-pollution\">fell</a> as a result of <a href=\"https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking?tab=chart&time=2000..2016&country=OWID_WRL\">improved access</a> to cleaner fuels for heating and cooking. But there is still much progress to be made, especially in Sub-Saharan Africa, where in most countries <a href=\"https://ourworldindata.org/grapher/access-to-clean-fuels-and-technologies-for-cooking\">less than 10% of households</a> have access to clean fuels for cooking. And, whilst progress has been made against indoor air pollution, high levels of <a href=\"https://ourworldindata.org/grapher/pm25-air-pollution\">outdoor pollution</a> remain a problem across many countries. Reducing air pollution levels would have many other benefits: it would not only reduce the number of cases of pneumonia but also limit the incidence of asthma in children for example.{ref}\u00a0WHO, U. (2006). <a href=\"http://www.euro.who.int/__data/assets/pdf_file/0005/78638/E90038.pdf\">Air quality guidelines: global update 2005.</a> p123-124. <em>World Health Organization</em>.\u00a0<br>{/ref}</p>\n\n\n\n<h4>Access to healthcare and treatment</h4>\n\n\n\n<p>A child with a suspected case of pneumonia \u2013 with symptoms of difficulty in breathing and coughing \u2013 should be taken to a healthcare provider so that the correct and immediate treatment can be provided. Delay in seeking treatment can increase the chances of a child dying.{ref}Ferdous, F., Ahmed, S., Das, S. K., Chisti, M. J., Nasrin, D., Kotloff, K. L., … & Wagatsuma, Y. (2018). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5970515/\">Pneumonia mortality and healthcare utilization in young children in rural Bangladesh: a prospective verbal autopsy study.</a><em>Tropical medicine and health</em>, <em>46</em>(1), 17.{/ref} However, as the map shows, seeking healthcare is still not as common as it should be. Globally, less than two-thirds of children with symptoms of pneumonia were taken to a healthcare provider in 2016. This figure is even lower in places where healthcare is most needed \u2014 just 47% in Sub-Saharan Africa.{ref} UNICEF DATA. (2018). <a href=\"https://data.unicef.org/topic/child-health/pneumonia/\"><em>Pneumonia in Children</em>.</a> [online] [Accessed 5 Sep. 2019]{/ref} </p>\n\n\n\n<p>As the map shows, the share of children with symptoms of pneumonia that are taken to a health provider is still low in many countries.</p>\n\n\n\n<iframe src=\"https://ourworldindata.org/grapher/pneumonia-careseeking\" style=\"width: 100%; height: 600px; border: 0px none;\"></iframe>\n\n\n\n<h4>Access to antibiotic treatment</h4>\n\n\n\n<p>Given that most cases of pneumonia are of bacterial origin, antibiotics are the general course of treatment. </p>\n\n\n\n<p>Due to the lack of resources, in places where pneumonia cases are most common, a quick diagnosis for the cause of disease is not always possible. Given the potential high risk of death from untreated pneumonia, the World Health Organisation (WHO) recommends antibiotic treatment depending on the disease symptoms and its severity before the cause of disease is known. Amoxicillin, ampicillin and gentamicin are the most commonly used antibiotics to treat pneumonia.{ref} World Health Organization. (2014). <a href=\"https://apps.who.int/iris/bitstream/handle/10665/137319/9789241507813_eng.pdf?sequence=1\"><em>Revised WHO classification and treatment of pneumonia in children at health facilities: quick reference guide</em></a> (No. WHO/FWC/MCA/14.9). World Health Organization.{/ref} Antibiotics are a relatively cheap and effective treatment, a course of amoxicillin costs less than 50 cents. {ref}Unicef.org. (2018). <a href=\"https://www.unicef.org/supply/files/Amoxicillin_DT_Supply_Update.pdf\"><em>Amoxicillin Dispersible Tablets: Market and Supply Update</em>.</a> [online] [Accessed 26 Sep. 2019]. {/ref} {ref}Unicef. (2016). <a href=\"https://www.unicef.org/publications/files/UNICEF_SOWC_2016.pdf\">The State of the World’s Children 2016</a>. <em>New York: United Nations Children\u2019s Fund</em>.{/ref}</p>\n\n\n\n<h4>Oxygen therapy</h4>\n\n\n\n<p>During pneumonia, alveoli in the lungs get filled with pus and fluid, which prevents oxygen from being transferred to the blood. Consequently, a condition known as hypoxaemia \u2013 a lack of oxygen \u2013 can develop. </p>\n\n\n\n<p>When a child with pneumonia develops hypoxaemia the risk of dying increases five-fold.{ref}Lazzerini, M., Sonego, M., & Pellegrin, M. C. (2015). <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4570717/\">Hypoxaemia as a mortality risk factor in acute lower respiratory infections in children in low and middle-income countries: systematic review and meta-analysis. </a><em>PLoS One</em>, <em>10</em>(9), e0136166.{/ref} Treatment with oxygen therapy (supplying oxygen-enriched air to the patient){ref}The air we breathe contains 21% of oxygen gas, but it is possible to concentrate this gas using special oxygen concentrators. The oxygen-enriched air can then be supplied to a person with pneumonia via a breathing mask, in this way compensating for reduced oxygen exchange in the lungs.{/ref} is one way to mitigate hypoxaemia.{ref}World Health Organization. (2016). <a href=\"https://www.who.int/maternal_child_adolescent/documents/child-oxygen-therapy/en/\">Oxygen therapy for children: a manual for health workers.</a><br>{/ref}</p>\n\n\n\n<p>A study from Papua New Guinea has shown that oxygen therapy can reduce the risk of death from severe pneumonia by 35%. However, the need for a specialist equipment to diagnose and treat hypoxaemia still poses a substantial barrier in low-resource settings. Since 2017, the WHO includes oxygen in its List of Essential Medicines.{ref} World Health Organization. (2019). <a href=\"https://www.who.int/medicines/publications/essentialmedicines/en/\">WHO model list of essential medicines: 7th list</a>, August 2019.<br>{/ref} Improved access to oxygen could save the lives of 120,000 children annually.{ref}Delarosa, J., Hayes, J., Pantjushenko, E., Keith, B., Ambler, G. and Lawrence, C. (2017). <a href=\"https://path.azureedge.net/media/documents/DRG_Oxygen_Primer.pdf\"><em>Oxygen Is Essential: A Policy and Advocacy Primer</em></a>. [online] PATH. [Accessed 5 Sep. 2019].{/ref} </p>\n\n\n\n<h2>Pneumococcal vaccines</h2>\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<h2>Additional Information</h2>\n\n\n\n<h3>What pathogens cause pneumonia?</h3>\n\n\n\n<p>Pneumonia is an infection of the lower respiratory tract that can be caused by multiple microbial pathogens. </p>\n\n\n\n<p>By far the most common cause of pneumonia in unvaccinated children is an infection by a bacterium called <em>Streptococcus pneumoniae</em>, simply referred to as pneumococcus. The Global Burden of Disease (GBD) study from 2018 has estimated that pneumococcus<em> </em>was responsible for 52% of 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> </em><em>The Lancet Infectious Diseases</em>, <em>18</em>(11), 1191-1210.{/ref}\u00a0<br></p>\n\n\n\n<p>Other pathogens which cause pneumonia in children are <em>Haemophilus influenzae</em> type b, respiratory syncytial virus (RSV), and the influenza virus. Each of these pathogens was responsible for less than 4% of lethal pneumonia cases 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> </em><em>The Lancet Infectious Diseases</em>, <em>18</em>(11), 1191-1210.{/ref} Despite being minor causes, it\u2019s important to continue developing treatments against these pathogens; they will become increasingly important as vaccination coverage for the most common causes increases. According to a study by Katherine O’Brien et <em>al.</em> (2019), when children are routinely vaccinated with pneumococcal and Hib vaccines, as many as 62% of pneumonia cases are caused by viral pathogens such as RSV.{ref}O’Brien, K. L., Baggett, H. C., Brooks, W. A., Feikin, D. R., Hammitt, L. L., Higdon, M. M., … & Madhi, S. A. (2019). <a href=\"https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)30721-4/fulltext\">Causes of severe pneumonia requiring hospital admission in children without HIV infection from Africa and Asia: the PERCH multi-country case-control study.</a><em> The Lancet</em>. {/ref}\u00a0</p>\n\n\n\n<h3>How is pneumonia acquired and transmitted?</h3>\n\n\n\n<p>Children can contract pneumonia in a number of ways. Pneumococcus and <em>H. influenzae </em>are bacteria that can be found in the upper respiratory tract of healthy individuals without any symptoms. Under circumstances when the conditions in the upper respiratory tract are compromised{ref}For example, when a secondary infection with a virus occurs, which may trigger multiplication of usually non-pathogenic bacteria.{/ref} these normally benign bacteria may move to the lower respiratory tract where they lead to pneumonia.{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} </p>\n\n\n\n<p>Pneumonia caused by bacterial and viral pathogens can be contagious and transmitted when a person coughs or sneezes. However, precautions such as sanitizing hands and surfaces, wearing a face mask if available and limiting close contact with a sick person can significantly limit the chances of transmission.\u00a0 \u00a0 </p>\n\n\n\n<p><br></p>\n", "protected": false }, "excerpt": { "rendered": "Pneumonia is the leading cause of death for children younger than 5 years.", "protected": false }, "date_gmt": "2018-11-04T12:09:26", "modified": "2022-03-04T16:19:48", "template": "", "categories": [ 46, 171 ], "menu_order": 311, "ping_status": "closed", "authors_name": [ "Bernadeta Dadonaite" ], "modified_gmt": "2022-03-04T16:19:48", "comment_status": "closed", "featured_media": 42330, "featured_media_paths": { "thumbnail": "/app/uploads/2021/04/Screen-Shot-2021-04-02-at-11.08.49-150x84.png", "medium_large": "/app/uploads/2021/04/Screen-Shot-2021-04-02-at-11.08.49-768x429.png" } } |