Editing Whooping cough (section)

==Epidemiology==
[[File:Whooping cough deaths per million by country 2019.svg|thumb|upright=1.3|Whooping cough deaths per million persons in 2019
{{Div col|small=yes|colwidth=10em}}
{{legend|#fef001|0.00–1.49}}
{{legend|#fcce02|1.50–2.99}}
{{legend|#faad03|3.00–5.99}}
{{legend|#f88b03|6.00–9.99}}
{{legend|#f44804|10.00–19.99}}
{{legend|#f22705|20.00–39.99}}
{{legend|#f00505|40.00–59.99}}
{{legend|#a80404|60.00–99.99}}
{{legend|#600202|100+}}
{{div col end}}]]

<!-- Global perspective -->
Pertussis is [[Endemic (epidemiology)|endemic]] worldwide. More than 151,000 cases were reported globally in 2018.<ref name="auto"/> However not all cases are reported or correctly diagnosed, especially in [[Developing country|developing countries]]. Pertussis is one of the leading causes of vaccine-preventable deaths worldwide.<ref name="cdcothercountries">{{cite web |title=Pertussis in Other Countries |url=https://www.cdc.gov/pertussis/php/global/?CDC_AAref_Val=https://www.cdc.gov/pertussis/countries.html |url-status=live |archive-url=https://web.archive.org/web/20130512041451/http://www.cdc.gov/pertussis/countries.html |archive-date=12 May 2013 |access-date=30 July 2024 |publisher=Centers for Disease Control and Prevention (CDC)}}</ref> A study in 2017 estimated the global burden of the disease to be 24 million cases per year with 160,000 deaths among young children, with about 90% of all cases occurring in developing countries.<ref>{{Cite journal |last1=Yeung |first1=Karene Hoi Ting |last2=Duclos |first2=Philippe |last3=Nelson |first3=E. Anthony S. |last4=Hutubessy |first4=Raymond Christiaan W. |date=September 2017 |title=An update of the global burden of pertussis in children younger than 5 years: a modelling study |url=https://pubmed.ncbi.nlm.nih.gov/28623146/ |journal=The Lancet. Infectious Diseases |volume=17 |issue=9 |pages=974–980 |doi=10.1016/S1473-3099(17)30390-0 |issn=1474-4457 |pmid=28623146}}</ref><ref name=cdcothercountries/>

Epidemics of the disease occur cyclically, every three to 5 years, both in areas with vaccination programs and those without.<ref name=":12">{{Cite journal |last1=Bouchez |first1=Valérie |last2=Guiso |first2=Nicole |date=October 2015 |editor-last=Carbonetti |editor-first=Nicholas |title=Bordetella pertussis, B. parapertussis, vaccines and cycles of whooping cough |url=https://academic.oup.com/femspd/article/580714/Bordetella-pertussis-B-parapertussis-vaccines-and |journal=Pathogens and Disease |language=en |volume=73 |issue=7 |pages=ftv055 |doi=10.1093/femspd/ftv055 |pmid=26242280 |issn=2049-632X}}</ref> Over time, immunity declines in those who have either been vaccinated or have recovered from infection.<ref>{{Cite journal |last1=Burdin |first1=Nicolas |last2=Handy |first2=Lori Kestenbaum |last3=Plotkin |first3=Stanley A. |date=December 2017 |title=What Is Wrong with Pertussis Vaccine Immunity? The Problem of Waning Effectiveness of Pertussis Vaccines |url=http://cshperspectives.cshlp.org/content/9/12/a029454 |journal=Cold Spring Harbor Perspectives in Biology |language=en |volume=9 |issue=12 |pages=a029454 |doi=10.1101/cshperspect.a029454 |issn=1943-0264 |pmc=5710106 |pmid=28289064}}</ref> In addition, infants are born who are susceptible to infection. An epidemic can occur once [[herd immunity]] decreases below a certain level.<ref name=":02">{{Cite web |date=15 March 2017 |title=Facts and figures - Whooping cough |url=https://www.health.nsw.gov.au/Infectious/whoopingcough/Pages/facts-and-figures.aspx |access-date=2024-03-26 |website=NSW Health |language=en}}</ref> It is also possible that the bacterium is evolving to evade vaccine-induced immunity.<ref>{{Cite web |date=2022-06-14 |title=Pertussis (whooping cough) - Epidemic Control Toolkit |url=https://epidemics.ifrc.org/pdf/223 |access-date=26 March 2024 |website=The International Federation of Red Cross}}</ref><ref name=":12" />

<!-- US specific perspective -->
Before vaccines, an average of 178,171 cases was reported in the U.S., with peaks reported every two to five years; more than 93% of reported cases occurred in children under 10 years of age. With the widespread introduction of the DTP combined vaccine (diphtheria tetanus and pertussis) in the 1940s, pertussis incidence fell dramatically to approximately 1,000 by 1976, when they fluctuated between 1,000 and 30,000 annually.<ref>{{Citation |last1=Kuchar |first1=E. |title=Pertussis: History of the Disease and Current Prevention Failure |date=2016 |work=Pulmonary Dysfunction and Disease |volume=934 |pages=77–82 |editor-last=Pokorski |editor-first=Mieczyslaw |url=http://link.springer.com/10.1007/5584_2016_21 |access-date=2024-09-30 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/5584_2016_21 |isbn=978-3-319-42009-7 |last2=Karlikowska-Skwarnik |first2=M. |last3=Han |first3=S. |last4=Nitsch-Osuch |first4=A.|pmid=27256351 }}</ref><ref>{{cite web |date=23 July 2024 |title=Pertussis Cases by Year |url=https://www.cdc.gov/pertussis/php/surveillance/pertussis-cases-by-year.html |archive-url= |archive-date= |access-date=30 September 2024 |website=Centers for Disease Control and Prevention}}</ref>

Cases recorded outside of the U.S. were also recorded{{When|date=October 2024}} at high numbers comparable to their populations. Before the vaccine was discovered, Sweden averaged nearly 3,000 children deaths per year. With their population only being 1.8 million in the years 1749-64 this number was very high. The London population during the same period recorded over 3,000 deaths. The rates in London continued to grow into the 18th century. These numbers show how the disease affected not only the U.S. but also those around the world.<ref>{{Cite journal |last=Weston |first=Robert |date=October 2012 |title=Whooping Cough: A Brief History to the 19th Century |url=https://utpjournals.press/doi/10.3138/cbmh.29.2.329 |journal=Canadian Bulletin of Medical History |language=en |volume=29 |issue=2 |pages=329–349 |doi=10.3138/cbmh.29.2.329 |pmid=28155549 |issn=0823-2105}}</ref>

According to the {{As of|2024|bare=yes}} CDC, reports that cases of whooping cough have reached their highest levels since 2014.<ref>{{Cite web |last=America |first=Good Morning |title=Whooping cough cases surge: CDC |url=https://www.goodmorningamerica.com/wellness/video/whooping-cough-cases-surge-cdc-114757172 |access-date=2024-10-14 |website=Good Morning America |language=en}}</ref> This year, there have been over 16,000 cases, marking a fourfold increase compared to last year’s total of more than 3,700 cases.<ref>{{Cite web |last=CDC |date=2024-10-10 |title=Pertussis Surveillance and Trends |url=https://www.cdc.gov/pertussis/php/surveillance/index.html |access-date=2024-10-14 |website=Whooping Cough (Pertussis) |language=en-us}}</ref> The CDC has also confirmed two deaths related to the illness.{{Citation needed|date=October 2024}} The United States is seeing a return to pre-pandemic trends, where annual cases typically exceed 10,000.<ref>{{Cite web |last=Leake |first=Lindsey |title=Whooping cough cases up 342% since 2023 as U.S. outbreak continues. What to know about symptoms and spread |url=https://fortune.com/well/article/whooping-cough-pertussis-symptoms-spread-2024/ |access-date=2024-10-14 |website=Fortune Well |language=en}}</ref>[[File:Whooping Cough (8744519854).jpg|thumb|An epidemiologist tests blood samples for pertussis during a 2010 outbreak.]]