Editing Polio (section)

==Epidemiology==
Major polio [[epidemic]]s were unknown before the 20th century; up until that time, polio was an endemic disease worldwide.<ref name="Trevelyan_2005">{{cite journal |vauthors=Trevelyan B, Smallman-Raynor M, Cliff A |year=2005 |title=The Spatial Dynamics of Poliomyelitis in the United States: From Epidemic Emergence to Vaccine-Induced Retreat, 1910–1971 |journal=Ann Assoc Am Geogr |volume=95 |issue=2 |pages=269–293 |doi=10.1111/j.1467-8306.2005.00460.x |pmc=1473032 |pmid=16741562}}</ref> Mothers who had survived polio infection passed on temporary immunity to their babies in the womb and through breast milk.<ref name="Baron2">{{cite book |url=https://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mmed.section.2862 |title=Picornaviruses: The Enteroviruses: Polioviruses ''in:'' Baron's Medical Microbiology |vauthors=Yin-Murphy M, Almond JW |publisher=University of Texas Medical Branch |year=1996 |isbn=0-9631172-1-1 |editor=Baron S |edition=4th |chapter=Picornaviruses |pmid=21413259 |display-editors=etal |archive-url=https://web.archive.org/web/20081207154734/http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mmed.section.2862 |archive-date=2008-12-07 |url-status=live}}</ref> As a result, an infant who encountered a polio infection generally suffered only mild symptoms and acquired a long-term immunity to the disease.<ref name=":0">{{cite web |title=Polio: a 20th century epidemic {{!}} Science Museum |url=https://www.sciencemuseum.org.uk/objects-and-stories/medicine/polio-20th-century-epidemic |access-date=2024-04-12 |website=www.sciencemuseum.org.uk}}</ref> With improvements in sanitation and hygiene during the 19th century, the general level of [[herd immunity]] in the population declined; this provided circumstances where [[epidemic]]s of polio became frequent.<ref name=":0" /> It is estimated that epidemic polio killed or paralysed over half a million people every year.<ref>{{cite web |title=History of polio vaccination |url=https://www.who.int/news-room/spotlight/history-of-vaccination/history-of-polio-vaccination |access-date=2024-04-10 |website=World health Organization}}</ref>

Following the widespread use of poliovirus vaccine in the mid-1950s, new cases of poliomyelitis declined dramatically in many industrialized countries.<ref name="Hinman">{{cite journal |author=Hinman A |year=1984 |title=Landmark perspective: Mass vaccination against polio |journal=JAMA |volume=251 |issue=22 |pages=2994–6 |doi=10.1001/jama.1984.03340460072029 |pmid=6371280}}</ref> Efforts to completely eradicate the disease started in 1988 and are ongoing.<ref name=":1" />

===Circulating vaccine-derived polioviruses===
The [[oral polio vaccine]], while highly effective, has the disadvantage that it contains a live virus which has been [[Attenuated vaccine|attenuated]] so that it cannot cause severe illness. The vaccine virus is excreted in the stool, and in under-immunized communities it can spread from person to person. This is known as '''circulating vaccine-derived poliovirus''' (cVDPV) or more simply as '''variant poliovirus'''.<ref name="www.cdc.gov2022" /><ref>{{cite web |title=GPEI-Variant Poliovirus (cVDPV) |url=https://polioeradication.org/polio-today/polio-prevention/the-virus/variant-poliovirus-cvdpv/ |access-date=2024-08-07 |website=Global Polio Eradication Initiative |language=en-GB}}</ref>

With prolonged transmission of this kind, the weakened virus can mutate and revert to a form that causes illness and paralysis. Cases of cVDPV now exceed wild-type cases, making it desirable to discontinue the use of the oral polio vaccine as soon as safely possible and instead use other types of polio vaccines.<ref name="www.cdc.gov2022" /><ref>{{cite web |title=GPEI-Vaccine-Derived Polioviruses |url=https://polioeradication.org/polio-today/polio-prevention/the-virus/vaccine-derived-polio-viruses/ |access-date=2022-09-03 |archive-date=28 August 2022 |archive-url=https://web.archive.org/web/20220828160534/https://polioeradication.org/polio-today/polio-prevention/the-virus/vaccine-derived-polio-viruses/ |url-status=live }}</ref>

===Eradication===
{{see also|Poliomyelitis eradication}}
[[File:The decade of the last recorded case of paralytic polio by country, OWID.svg|thumb|upright=1.8|The decade of the last recorded case of paralytic polio. Since the creation of this image, Nigeria has been certified free of wild polio as of August 2020.<ref>{{cite web |title=The decade of the last recorded case of paralytic polio by country |url=https://ourworldindata.org/grapher/the-decade-of-the-last-recorded-case-of-paralytic-polio-by-country |website=Our World in Data |access-date=4 March 2020 |archive-date=13 May 2020 |archive-url=https://web.archive.org/web/20200513120540/https://ourworldindata.org/grapher/the-decade-of-the-last-recorded-case-of-paralytic-polio-by-country |url-status=live }}</ref>]]
A global effort to [[Eradication of infectious disease|eradicate]] polio – the [[Global Polio Eradication Initiative]] – began in 1988, led by the [[World Health Organization]], [[UNICEF]], and [[The Rotary Foundation]].<ref name=":1">{{cite web| vauthors = Vaught M |title=Polio Vaccine Celebrates 60th Anniversary|url=https://www.rotary.org/en/polio-vaccine-celebrates-60th-anniversary|website=Rotary International|access-date=11 November 2015|date=10 April 2015|archive-url=https://web.archive.org/web/20151117023228/https://www.rotary.org/en/polio-vaccine-celebrates-60th-anniversary|archive-date=17 November 2015}}</ref> Polio is one of only two diseases currently the subject of a global [[eradication of infectious diseases|eradication program]], the other being [[Guinea worm disease]].<ref>{{cite web| vauthors = Akst J |title=Driven to Extinction|url=http://www.the-scientist.com/?articles.view/articleNo/43382/title/Driven-to-Extinction/|website=The Scientist|access-date=11 November 2015|date=1 July 2015|url-status=live|archive-url=https://web.archive.org/web/20151118224852/http://www.the-scientist.com/?articles.view%2FarticleNo%2F43382%2Ftitle%2FDriven-to-Extinction%2F|archive-date=18 November 2015}}</ref> So far, the only diseases completely eradicated by humankind are [[smallpox]], declared eradicated in 1980,<ref name="WHO_smallpox">{{cite web|title=Smallpox |work=WHO Factsheet |url=https://www.who.int/mediacentre/factsheets/smallpox/en/ |access-date=23 August 2008 |archive-url=https://web.archive.org/web/20070921235036/http://www.who.int/mediacentre/factsheets/smallpox/en/ |archive-date=21 September 2007}}</ref><ref>{{cite web|title=The Smallpox Eradication Programme – SEP (1966–1980)|url=https://www.who.int/features/2010/smallpox/en/|website=WHO|access-date=11 November 2015|archive-url=https://web.archive.org/web/20151109123858/http://www.who.int/features/2010/smallpox/en/|archive-date=9 November 2015}}</ref> and [[rinderpest]], declared eradicated in 2011.<ref>{{cite press release|title=No more deaths from rinderpest|url=http://www.oie.int/for-the-media/press-releases/detail/article/no-more-deaths-from-rinderpest/|publisher=[[World Organisation for Animal Health]]|access-date=11 November 2015|date=25 May 2011|archive-url=https://web.archive.org/web/20150924072257/http://www.oie.int/for-the-media/press-releases/detail/article/no-more-deaths-from-rinderpest/|archive-date=24 September 2015}}</ref> In April 2012, the World Health Assembly declared that the failure to completely eradicate polio would be a programmatic emergency for global public health, and that it "must not happen".<ref>{{cite book |author=World Health Assembly |year=2012 |title=Poliomyelitis: intensification of the global eradication initiative. Agenda item A65/20 |url=http://apps.who.int/gb/ebwha/pdf_files/wha65/A65_20-en.pdf |location=Geneva, Switzerland |publisher=World Health Organization |access-date=7 December 2013 |url-status=live |archive-url=https://web.archive.org/web/20131109143313/http://apps.who.int/gb/ebwha/pdf_files/WHA65/A65_20-en.pdf |archive-date=9 November 2013}}</ref>

These efforts have hugely reduced the number of cases; from an estimated 350,000 cases in 1988 to a low of 483 cases in 2001, after which it remained at a level of about 1,000–2000 cases per year for a number of years.<ref name="eradication">{{cite journal |author=Centers for Disease Control Prevention (CDC) |title=Update on vaccine-derived polioviruses |journal=MMWR. Morbidity and Mortality Weekly Report |volume=55 |issue=40 |pages=1093–1097 |date=October 2006 |pmid=17035927}}</ref><ref name="morbidity">{{cite journal |author=Centers for Disease Control and Prevention (CDC) |title=Progress toward interruption of wild poliovirus transmission—worldwide, January 2007 – April 2008 |url=https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5718a4.htm |url-status=live |journal=MMWR. Morbidity and Mortality Weekly Report |volume=57 |issue=18 |pages=489–494 |date=May 2008 |pmid=18463607 |archive-url=https://web.archive.org/web/20170619054233/https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5718a4.htm |archive-date=19 June 2017}}</ref>

By 2015, polio was believed to remain [[Endemic (epidemiology)|naturally spreading]] in only two countries, [[Pakistan]] and [[Afghanistan]],<ref name="eradication1" /><ref name="GlobalPolio2015">{{cite web|title=Wild poliovirus type 1 and Circulating vaccine-derived poliovirus cases|url=http://www.polioeradication.org/dataandmonitoring/poliothisweek.aspx|website=Global Polio Eradication Initiative|access-date=26 December 2015|date=23 December 2015|url-status=live|archive-url=https://web.archive.org/web/20151224045950/http://www.polioeradication.org/Dataandmonitoring/Poliothisweek.aspx|archive-date=24 December 2015}}</ref> although it continued to cause outbreaks in other nearby countries due to hidden or re-established transmission.<ref>Wild Poliovirus case list 2000–2010; data in WHO/HQ as of 9 November 2010 {{cite web |url=http://www.polioeradication.org/tabid/167/iid/80/Default.aspx |title=Emergency appeal for Congo polio outbreak |access-date=17 November 2010 |archive-url=https://web.archive.org/web/20101222075237/http://www.polioeradication.org/tabid/167/iid/80/Default.aspx |archive-date=22 December 2010 }}</ref>

Global surveillance for polio takes two forms. Cases of [[Flaccid paralysis|acute flaccid paralysis]] (AFP) are tested for the presence and type of poliovirus. In addition, environmental and [[Wastewater surveillance|wastewater]] samples are tested for the presence of poliovirus - this is an effective method of detecting circulating virus which has not given rise to severe symptoms.<ref>{{Cite web |date=14 August 2024 |title=Surveillance Indicators |url=https://polioeradication.org/polio-today/polio-now/surveillance-indicators/ |access-date=14 August 2024 |website=Global Polio Eradication Initiative}}</ref> Here is a summary of both wild polio (WPV) and variant polio (cVDPV) prevalence over the last 5 years:<ref name=":52">{{Cite web |date=9 April 2024 |title=Global Wild Poliovirus 2018–2024 |url=https://polioeradication.org/wp-content/uploads/2024/04/weekly-polio-analyses-WPV-20240409.pdf |website=Global Polio Eradication Initiative - World Health Organization}}</ref><!--update this list annually, delete oldest entry and add new-->

* 2019 - 147 cases of WPV1 in Pakistan, and 29 cases in Afghanistan. None were reported elsewhere in the world. cVDPV was detected in 19 countries with 378 confirmed cases.<ref name=":02">{{Cite journal |last1=Bigouette |first1=John Paul |last2=Wilkinson |first2=Amanda L. |last3=Tallis |first3=Graham |last4=Burns |first4=Cara C. |last5=Wassilak |first5=Steven G. F. |last6=Vertefeuille |first6=John F. |date=2021-08-27 |title=Progress Toward Polio Eradication — Worldwide, January 2019–June 2021 |journal=Morbidity and Mortality Weekly Report |volume=70 |issue=34 |pages=1129–1135 |doi=10.15585/mmwr.mm7034a1 |issn=0149-2195 |pmc=8389387 |pmid=34437527}}</ref>
* 2020 - 84 WPV1 cases in Pakistan, 56 in Afghanistan. 32 countries reported cVDPV detection, and there were 1,103 cVDPV cases.<ref name=":02" />
* In 2021, there were just six confirmed cases of wild poliovirus — one in Pakistan, four in Afghanistan, and one in Malawi. The case in Malawi, the country's first in almost three decades and the first in Africa in five years, was seen as a significant setback to the eradication effort.<ref name="GPEI-Malawi2">{{cite press release |title=GPEI Statement on WPV1 in Malawi: Wild poliovirus type 1 detected in Lilongwe, Malawi |date=2022-02-17 |publisher=Global Polio Eradication Initiative – World Health Organization |url=https://polioeradication.org/news-post/gpei-statement-on-wpv1-in-malawi/}}</ref> 23 countries detected cVDPV, with 698 cases.<ref name=":12">{{cite journal |last=Lee |first=Scarlett E. |date=2023 |title=Progress Toward Poliomyelitis Eradication — Worldwide, January 2021–March 2023 |url=https://www.cdc.gov/mmwr/volumes/72/wr/mm7219a3.htm |journal=MMWR. Morbidity and Mortality Weekly Report |language=en-US |volume=72 |issue=19 |pages=517–522 |doi=10.15585/mmwr.mm7219a3 |issn=0149-2195 |pmc=10208367 |pmid=37167156}}</ref>
* In 2022, there were 30 confirmed cases of WPV1 reported to WHO, with two cases in Pakistan and 20 Afghanistan respectively, while eight non-endemic cases were recorded in Mozambique, the first cases in the country since 1992. The Mozambique cases derived from the strain of Pakistani origin that caused two confirmed cases in Malawi in 2021.<ref>{{cite press release |title=GPEI statement on Mozambique WPV1 detection |date=2022-05-18 |publisher=Global Polio Eradication Initiative – World Health Organization |url=https://polioeradication.org/news-post/gpei-statement-on-mozambique-wpv1-detection/}}</ref> 24 countries detected cVDPV, with 881 cases.<ref name=":12" />
* In 2023, twelve cases of WPV1 were reported, six each in Afghanistan and Pakistan. 32 countries reported cVDPV, with 524 cases.<ref>{{cite journal |last=Geiger |first=Keri |date=2024 |title=Progress Toward Poliomyelitis Eradication — Worldwide, January 2022–December 2023 |url=https://www.cdc.gov/mmwr/volumes/73/wr/mm7319a4.htm |journal=MMWR. Morbidity and Mortality Weekly Report |language=en-US |volume=73 |issue=19 |pages=441–446 |doi=10.15585/mmwr.mm7319a4 |issn=0149-2195 |pmc=11115430 |pmid=38753550}}</ref>

==== Afghanistan and Pakistan ====
{{see also|Polio in Pakistan}}
The last remaining region with wild polio cases are the [[South Asia]]n countries [[Afghanistan]] and [[Pakistan]].<ref name=":5">{{cite web |date=9 April 2024 |title=Global Wild Poliovirus 2018–2024 |url=https://polioeradication.org/wp-content/uploads/2024/04/weekly-polio-analyses-WPV-20240409.pdf |website=Global Polio Eradication Initiative - World Health Organization}}</ref>

During 2011, the [[Central Intelligence Agency|CIA]] ran a fake hepatitis vaccination clinic in [[Abbottabad, Pakistan]], in [[Killing of Osama bin Laden#Intelligence gathering|an attempt to locate]] [[Osama bin Laden]]. This destroyed trust in vaccination programs in the region.<ref>{{Cite journal|vauthors=Kennedy J|date=October 2017|title=How Drone Strikes and a Fake Vaccination Program Have Inhibited Polio Eradication in Pakistan: An Analysis of National Level Data|journal=International Journal of Health Services: Planning, Administration, Evaluation|volume=47|issue=4|pages=807–25|doi=10.1177/0020731417722888|issn=1541-4469|pmid=28764582|s2cid=25844860|url=http://qmro.qmul.ac.uk/xmlui/handle/123456789/25135|access-date=4 May 2021|archive-date=20 October 2021|archive-url=https://web.archive.org/web/20211020082540/https://qmro.qmul.ac.uk/xmlui/handle/123456789/25135|url-status=live}}</ref><ref>{{Cite news|vauthors=McNeil Jr DG|date=9 July 2012|title=C.I.A. Vaccine Ruse May Have Harmed the War on Polio|work=The New York Times|url=https://www.nytimes.com/2012/07/10/health/cia-vaccine-ruse-in-pakistan-may-have-harmed-polio-fight.html|access-date=3 July 2020|issn=0362-4331|archive-date=10 July 2012|archive-url=https://web.archive.org/web/20120710192832/https://www.nytimes.com/2012/07/10/health/cia-vaccine-ruse-in-pakistan-may-have-harmed-polio-fight.html|url-status=live}}</ref> There were attacks and deaths among vaccination workers; 66 vaccinators were killed in 2013 and 2014.<ref>{{cite web|title=Pakistan's fight against polio clashes with battle against Taliban – The National|url=http://www.thenational.ae/world/south-asia/pakistans-fight-against-polio-clashes-with-battle-against-taliban#page2|url-status=live|archive-url=https://web.archive.org/web/20150928122419/http://www.thenational.ae/world/south-asia/pakistans-fight-against-polio-clashes-with-battle-against-taliban#page2|archive-date=28 September 2015|vauthors=Khan T|date=20 January 2015}}</ref><ref name="thenational.ae" /> In Afghanistan, the [[Taliban]] banned house-to-house polio vaccination between 2018 and 2021.<ref>{{cite web |title=House-to-house polio vaccination set to recommence across Afghanistan in November |url=https://www.unicef.org/press-releases/house-house-polio-vaccination-set-recommence-across-afghanistan-november |access-date=2022-06-30 |website=www.unicef.org |archive-date=30 June 2022 |archive-url=https://web.archive.org/web/20220630172858/https://www.unicef.org/press-releases/house-house-polio-vaccination-set-recommence-across-afghanistan-november |url-status=live}}</ref> These factors have set back efforts to eliminate polio by means of vaccination in these countries.<ref>{{cite news |date=20 April 2016 |title=Seven shot dead in Pakistan polio attack |publisher=[[BBC News]] |url=https://www.bbc.com/news/world-asia-36090891 |access-date=25 January 2021 |archive-date=4 October 2019 |archive-url=https://web.archive.org/web/20191004045256/https://www.bbc.com/news/world-asia-36090891 |url-status=live}}</ref>

In Afghanistan, 80 cases of polio were reported from 35 districts during 2011. Incidence over the subsequent 10 years has declined to just 4 cases in 2 districts during 2021.<ref>{{cite web |last=World Health Organization |first=Global Polio Eradication Initiative |date=2022-06-30 |title=Afghanistan Polio Eradication Initiative Annual Report 2021 |url=https://polioeradication.org/wp-content/uploads/2022/06/Afghanistan-Annual-Report-2021.pdf |access-date=30 June 2022 |archive-date=5 June 2022 |archive-url=https://web.archive.org/web/20220605045904/https://polioeradication.org/wp-content/uploads/2022/06/Afghanistan-Annual-Report-2021.pdf |url-status=live}}</ref><ref>{{cite web |title=GPEI-Afghanistan |url=https://polioeradication.org/where-we-work/afghanistan/ |access-date=2022-06-30 |language=en-GB |archive-date=30 June 2022 |archive-url=https://web.archive.org/web/20220630175010/https://polioeradication.org/where-we-work/afghanistan/ |url-status=live}}</ref>

In Pakistan, cases dropped by 97 percent from 2014 to 2018;<ref>{{cite news |title=Nationwide polio campaign starts today |url=https://www.dawn.com/news/1450490 |work=Dawn |date=10 December 2018 |quote=It shows that the number of annual polio cases has decreased by 97 per cent from 306 reported in 2014. |access-date=11 January 2019 |archive-date=6 July 2020 |archive-url=https://web.archive.org/web/20200706000032/https://www.dawn.com/news/1450490 |url-status=live }}</ref> reasons include 440&nbsp;million [[United Arab Emirates dirham|dirham]] support from the [[United Arab Emirates]] to vaccinate more than ten million children,<ref name="thenational.ae">{{cite web|author=The National staff|date=18 April 2015|title=UAE polio campaign vaccinates millions of Pakistani children|url=http://www.thenational.ae/uae/health/uae-polio-campaign-vaccinates-millions-of-pakistani-children|url-status=live|archive-url=https://web.archive.org/web/20150910053250/http://www.thenational.ae/uae/health/uae-polio-campaign-vaccinates-millions-of-pakistani-children|archive-date=10 September 2015}}</ref><ref>{{cite web|url=http://www.thenational.ae/uae/health/17-million-children-to-be-vaccinated-against-polio-in-pakistan|title=17 million children to be vaccinated against polio in Pakistan|author=The National staff|date=24 January 2015|url-status=live|archive-url=https://web.archive.org/web/20150910054826/http://www.thenational.ae/uae/health/17-million-children-to-be-vaccinated-against-polio-in-pakistan|archive-date=10 September 2015}}</ref> changes in the military situation, and arrests of some of those who attacked polio workers.<ref name=BBC2016>{{cite news|url=https://www.bbc.co.uk/news/world-asia-36300034|title=Pakistan could beat polio in months, says WHO|date=16 May 2016|publisher=BBC News|access-date=16 May 2016|url-status=live|archive-url=https://web.archive.org/web/20160516114003/http://www.bbc.co.uk/news/world-asia-36300034|archive-date=16 May 2016}}</ref><ref>{{cite news|url=https://www.bbc.com/news/world-asia-32996624|title=Polio in Pakistan: Drop of 70% recorded this year|publisher=BBC News|url-status=live|archive-url=https://web.archive.org/web/20150604035928/http://www.bbc.com/news/world-asia-32996624|archive-date=4 June 2015|date=3 June 2015}}</ref>

==== Americas ====
The [[Americas]] were declared polio-free in 1994.<ref name=MMWR_1994>{{cite journal | title = Certification of poliomyelitis eradication—the Americas, 1994 | journal = MMWR. Morbidity and Mortality Weekly Report | volume = 43 | issue = 39 | pages = 720–2 | date = October 1994 | pmid = 7522302 | url = https://www.cdc.gov/mmwr/preview/mmwrhtml/00032760.htm | url-status = live | archive-url = https://web.archive.org/web/20170521163051/https://www.cdc.gov/mmwr/preview/mmwrhtml/00032760.htm | archive-date = 21 May 2017 | author1 = Centers for Disease Control Prevention (CDC) }}</ref> The last known case was a boy in [[Peru]] in 1991.<ref>{{Cite web|url=https://www.historyofvaccines.org/content/polio-declared-eliminated-americas|title=Polio Declared Eliminated from the Americas &#124; History of Vaccines|access-date=23 May 2020|archive-date=9 July 2020|archive-url=https://web.archive.org/web/20200709100144/https://www.historyofvaccines.org/content/polio-declared-eliminated-americas}}</ref> The US [[Centers for Disease Control and Prevention]] recommends polio vaccination boosters for travelers and those who live in countries where the disease is endemic.<ref>{{cite web |date=2 June 2014 |title=Guidance to US Clinicians Regarding New WHO Polio Vaccination Requirements for Travel by Residents of and Long-term Visitors to Countries with Active Polio Transmission |url=http://emergency.cdc.gov/han/han00362.asp |archive-url=https://web.archive.org/web/20140604000158/http://emergency.cdc.gov/han/han00362.asp |archive-date=4 June 2014 |access-date=4 June 2014 |website=CDC}}</ref>

In July 2022, the US state of [[New York (state)|New York]] reported a polio case for the first time in almost a decade in the country; this was attributed to a vaccine-derived strain of the virus.<ref>{{cite web |last=Kimball |first=Spencer |title=How polio came back to New York for the first time in decades, silently spread and left a patient paralyzed |url=https://www.cnbc.com/2022/10/04/how-polio-silently-spread-in-new-york-and-left-a-person-paralyzed.html |access-date=2022-11-15 |publisher=CNBC |date=4 October 2022 |archive-date=15 November 2022 |archive-url=https://web.archive.org/web/20221115092909/https://www.cnbc.com/2022/10/04/how-polio-silently-spread-in-new-york-and-left-a-person-paralyzed.html |url-status=live}}</ref>

==== Western Pacific ====
In 2000, polio was declared to have been officially eliminated in 37 Western Pacific countries, including China and Australia.<ref name=Pacific>{{cite journal | title = General News. Major Milestone reached in Global Polio Eradication: Western Pacific Region is certified Polio-Free | journal = Health Education Research | year = 2001 | volume = 16 | issue = 1 | pages = 109–114 | doi = 10.1093/her/16.1.109 | bibcode = 2001PDiff..16..110Y | last1 = Yamazaki | first1 = S. | last2 = Toraya | first2 = H. }}</ref><ref name="D'Souza_2002">{{cite journal | vauthors = D' Souza RM, Kennett M, Watson C | title = Australia declared polio free | journal = Communicable Diseases Intelligence Quarterly Report | volume = 26 | issue = 2 | pages = 253–60 | year = 2002 | pmid = 12206379 }}</ref>

Despite eradication ten years earlier, an outbreak was confirmed in China in September 2011, involving a strain common in Pakistan.<ref>{{cite news | url=http://www.cnn.com/2011/09/21/health/china-polio-outbreak/index.html | work=CNN | title=New polio outbreak hits China - CNN.com | date=21 September 2011 | url-status=live | archive-url=https://web.archive.org/web/20120101174601/http://www.cnn.com/2011/09/21/health/china-polio-outbreak/index.html | archive-date=1 January 2012 }}</ref>

In September 2019, the [[Department of Health (Philippines)|Department of Health of the Philippines]] declared a polio outbreak in the country after a single case in a 3-year-old girl.<ref name="Polio in PH">{{Cite news |vauthors=Paris J |url=https://www.rappler.com/nation/240493-polio-back-philippines |title=PH declares polio outbreak as disease returns after 19 years |work=[[Rappler]] |location=Manila, Philippines |date=19 September 2019 |access-date=22 September 2019 |archive-date=22 September 2019 |archive-url=https://web.archive.org/web/20190922014536/https://www.rappler.com/nation/240493-polio-back-philippines |url-status=live }}</ref> In December 2019, acute poliomyelitis was confirmed in an infant in [[Sabah|Sabah state]], [[Borneo]], [[Malaysia]].<ref name="VOAMalaysia">{{cite news |date=9 December 2019 |title=Malaysia Reports First Case of Polio in 27 Years |work=[[VOA News]] |agency=[[Associated Press]] |url=https://www.voanews.com/a/science-health_malaysia-reports-first-case-polio-27-years/6180817.html |access-date=10 December 2019 |archive-date=8 January 2020 |archive-url=https://web.archive.org/web/20200108134117/https://www.voanews.com/science-health/malaysia-reports-first-case-polio-27-years |url-status=live }}</ref> Subsequently, a further three polio cases were reported, with the last case reported in January 2020. Both outbreaks were found to be linked instances of vaccine-derived poliomyelitis.<ref>{{Cite journal |last1=Snider |first1=Cynthia J. |last2=Boualam |first2=Liliane |last3=Tallis |first3=Graham |last4=Takashima |first4=Yoshihiro |last5=Abeyasinghe |first5=Rabindra |last6=Lo |first6=Ying-Ru |last7=Grabovac |first7=Varja |last8=Avagyan |first8=Tigran |last9=Aslam |first9=Syeda Kanwal |last10=Eltayeb |first10=Abu Obeida |last11=Aung |first11=Khin Devi |last12=Wang |first12=Xiaojun |last13=Shrestha |first13=Achyut |last14=Ante-Orozco |first14=Carla |last15=Silva |first15=Maria Wilda T. |date=2022-03-23 |title=Concurrent outbreaks of circulating vaccine-derived poliovirus types 1 and 2 affecting the Republic of the Philippines and Malaysia, 2019–2021 |journal=Vaccine |volume=41 |issue=Suppl 1 |pages=A58–A69 |doi=10.1016/j.vaccine.2022.02.022 |pmid=35337673 |pmc=10546869 |s2cid=247652342 |issn=0264-410X |doi-access=free}}</ref>

==== Europe ====
[[Europe]] was declared polio-free in 2002.<ref name=WHO_Europe_2002>{{cite press release |title=Europe achieves historic milestone as Region is declared polio-free |publisher=European Region of the World Health Organization |date=21 June 2002 |url=https://www.who.int/mediacentre/news/releases/releaseeuro02/en/index.html |access-date=23 August 2008 |archive-url=https://web.archive.org/web/20080916065107/http://www.who.int/mediacentre/news/releases/releaseeuro02/en/index.html |archive-date=16 September 2008}}</ref>

==== Southeast Asia ====
On 27 March 2014, the WHO announced the eradication of poliomyelitis in the South-East Asia Region, which includes eleven countries: [[Bangladesh]], [[Bhutan]], [[North Korea]], [[India]], [[Indonesia]], [[Maldives]], [[Myanmar]], [[Nepal]], [[Sri Lanka]], [[Thailand]] and [[Timor-Leste]].<ref name="eradication1">{{cite web |url=http://www.searo.who.int/mediacentre/releases/2014/pr1569/en/ |title=WHO South-East Asia Region certified polio-free |publisher=WHO |date=27 March 2014 |access-date=27 March 2014 |archive-url=https://web.archive.org/web/20140327235218/http://www.searo.who.int/mediacentre/releases/2014/pr1569/en/ |archive-date=27 March 2014}}</ref> With the addition of this region, 80 per cent of the world population was considered to be living in polio-free regions.<ref name="eradication1"/>

==== Middle East ====
In [[Syria]], difficulties in executing immunization programs in the ongoing [[Syrian Civil War|civil war]] led to a return of polio, probably in 2012,<ref>{{cite news |url=https://www.bbc.com/news/magazine-26734465 |title=Polio in Syria: An outbreak that threatens the Middle East |publisher=BBC News |url-status=live |archive-url=https://web.archive.org/web/20150703194812/http://www.bbc.com/news/magazine-26734465 |archive-date=3 July 2015 |date=26 March 2014 |vauthors=Whewell T}}</ref> acknowledged by the WHO in 2013.<ref>{{cite news |url=http://www.dnaindia.com/health/report-syria-polio-cases-spread-to-damascus-and-aleppo-who-1925221 |work=DNA |title=Syria polio cases spread to Damascus and Aleppo – WHO |date=26 November 2013 |access-date=26 November 2013 |url-status=live |archive-url=https://web.archive.org/web/20131128140419/http://www.dnaindia.com/health/report-syria-polio-cases-spread-to-damascus-and-aleppo-who-1925221 |archive-date=28 November 2013}}</ref><ref>{{cite news |url=https://edition.cnn.com/2013/10/29/health/syria-polio/index.html |title=WHO: Polio cases confirmed in Syria |date=29 October 2013 |vauthors=Watkins T |publisher=CNN |access-date=24 January 2014 |url-status=live |archive-url=https://web.archive.org/web/20140203121111/http://edition.cnn.com/2013/10/29/health/syria-polio/index.html |archive-date=3 February 2014}}</ref> 15 cases were confirmed among children in [[Syria]] between October and November 2013 in [[Deir Ezzor]]. Later, two more cases, one each in rural [[Damascus]] and [[Aleppo]], were identified. It was the first outbreak in Syria since 1999. Doctors and international public health agencies report more than 90 cases of polio in Syria, with fears of contagion in rebel areas from lack of sanitation and safe-water services.<ref name="Suppressed">{{cite journal| vauthors = Sparrow A |title=Syria's Polio Epidemic: The Suppressed Truth|journal=New York Review|date=20 February 2014|url=http://www.nybooks.com/articles/archives/2014/feb/20/syrias-polio-epidemic-suppressed-truth/?insrc=hpma|access-date=23 January 2014|quote=Ninety or so afflicted children may sound like a small number, but they are only a tiny manifestation of an enormous problem, since for each crippled child up to one thousand more are silently infected. Polio is so contagious that a single case is considered a public health emergency. Ninety cases could mean some 90,000 people infected, each a carrier invisibly spreading the disease to others for weeks on end. |url-status=live |archive-url=https://web.archive.org/web/20140125214019/http://www.nybooks.com/articles/archives/2014/feb/20/syrias-polio-epidemic-suppressed-truth/?insrc=hpma |archive-date=25 January 2014}}</ref> A vaccination campaign in Syria operated under gunfire and led to the deaths of several vaccinators,<ref>{{cite web |last=Motlagh |first=Jason |title=Fighting Polio Amid the Chaos of Syria's Civil War |url=http://news.nationalgeographic.com/2015/03/150305-polio-syria-iraq-islamic-state-refugees-vaccination-virus-jihad/ |work=National Geographic |date=5 March 2015 |archive-url=https://web.archive.org/web/20160105100254/http://news.nationalgeographic.com/2015/03/150305-polio-syria-iraq-islamic-state-refugees-vaccination-virus-jihad/ |archive-date=5 January 2016}}</ref> but returned vaccination coverage to pre-war levels.<ref>{{cite news |vauthors=Westall S |title=Polio immunisation rate in Syria close to pre-war level – WHO |url=https://www.reuters.com/article/mideast-crisis-syria-polio-idUSL6N0V70ZW20150128 |url-status=live |publisher=[[Reuters]] |date=28 January 2015 |archive-url=https://web.archive.org/web/20150924212925/http://www.reuters.com/article/2015/01/28/mideast-crisis-syria-polio-idUSL6N0V70ZW20150128 |archive-date=24 September 2015}}</ref> Syria is currently free of polio, but is considered "at risk".<ref>{{cite web |title=GPEI-Syrian Arab Republic |url=https://polioeradication.org/where-we-work/syrian-arab-republic/ |access-date=2022-07-01 |language=en-GB |archive-date=1 July 2022 |archive-url=https://web.archive.org/web/20220701105928/https://polioeradication.org/where-we-work/syrian-arab-republic/ |url-status=live}}</ref>

In 2024, the [[Gaza Health Ministry]] reported that several children have shown symptoms consistent with polio, with laboratory tests confirming that a 10-month-old child is infected with the virus.<ref>{{cite news |last=Pietsch |first=Bryan |date=2024-08-17 |title=Gaza faces public health crisis with first confirmed case of polio |url=https://www.washingtonpost.com/world/2024/08/17/gaza-strip-polio-case-confirmed/ |access-date=2024-08-18 |newspaper=[[The Washington Post]] |language=en-US |issn=0190-8286}}</ref> In 2022, prior to the [[Gaza–Israel conflict|Israel-Hamas conflict]], routine immunization coverage of eligible children exceeded 99%, but fell to less than 90% by the first quarter of 2024, according to the [[World Health Organization|WHO]].<ref>{{cite web |title=Humanitarian pauses vital for critical polio vaccination campaign in the Gaza Strip |url=https://www.who.int/news/item/16-08-2024-humanitarian-pauses-vital-for-critical-polio-vaccination-campaign-in-the-gaza-strip |access-date=2024-12-14 |website=www.who.int}}</ref> [[United Nations]] Secretary-General [[António Guterres]] urged for a weeklong cease-fire in Gaza to facilitate vaccinations and prevent a potential polio outbreak, emphasizing the risk faced by many children.<ref>{{cite news |last1=Fassihi |first1=Farnaz |last2=Livni |first2=Ephrat |date=2024-08-16 |title=The U.N. Calls for a Temporary Truce to Fight Polio in Gaza |url=https://www.nytimes.com/2024/08/16/world/middleeast/gaza-polio-crisis.html |access-date=2024-08-18 |work=The New York Times |language=en-US |issn=0362-4331}}</ref>

==== Africa ====
[[File:Polio Vaccination - Egypt (16868521330).jpg|thumb|Polio vaccination in Egypt]]
In 2003, in [[Northern Region, Nigeria|northern Nigeria]]&nbsp;– a country that at that time was considered provisionally polio free&nbsp;– a [[fatwa]] was issued declaring that the polio vaccine was designed to render children sterile.<ref>{{cite web |url=http://www.unicef.org/cbsc/index_49534.html |title=Polio Eradication Efforts in Nigeria and India |access-date=25 December 2013 |website=UNICEF |url-status=live |archive-url=https://web.archive.org/web/20131225195534/http://www.unicef.org/cbsc/index_49534.html |archive-date=25 December 2013}}</ref> Subsequently, polio reappeared in Nigeria and spread from there to several other countries. In 2013, nine health workers administering polio vaccine were targeted and killed by gunmen on motorcycles in [[Kano (city)|Kano]], but this was the only attack.<ref>{{cite news |url=https://www.bbc.co.uk/news/world-africa-21381773 |title=Nigeria polio vaccinators shot dead in Kano |publisher=BBC News |url-status=live |archive-url=https://web.archive.org/web/20141228034024/http://www.bbc.co.uk/news/world-africa-21381773 |archive-date=28 December 2014 |date=8 February 2013}}</ref><ref>{{cite news |url=https://www.bbc.co.uk/news/world-africa-33650543 |publisher=BBC News |title=Nigeria marks one year without recorded polio case |date=24 July 2015 |url-status=live |archive-url=https://web.archive.org/web/20150724162448/http://www.bbc.co.uk/news/world-africa-33650543 |archive-date=24 July 2015}}</ref> Local traditional and religious leaders and polio survivors worked to revive the campaign,<ref name="reuters.com">{{cite news |url=https://www.reuters.com/article/us-health-polio-nigeria-idUSKCN0PX2RF20150723 |publisher=Reuters |title=Nigeria marks polio-free year, raising global eradication hopes |date=23 July 2015 |url-status=live |archive-url=https://web.archive.org/web/20151119091530/http://www.reuters.com/article/2015/07/23/us-health-polio-nigeria-idUSKCN0PX2RF20150723 |archive-date=19 November 2015}}</ref> and Nigeria was removed from the polio-endemic list in September 2015 after more than a year without any cases,<ref>{{cite news |url=https://www.who.int/mediacentre/news/releases/2015/nigeria-polio/en/ |publisher=[[WHO]] |title=WHO Removes Nigeria from Polio-Endemic List |date=26 September 2015 |access-date=8 January 2016 |archive-url=https://web.archive.org/web/20160119165136/http://www.who.int/mediacentre/news/releases/2015/nigeria-polio/en/ | archive-date=19 January 2016 }}</ref> only to be restored to the list in 2016 when two cases were detected.<ref name=Nigeria2016>{{cite web|title=Government of Nigeria reports 2 wild polio cases, first since July 2014|url=https://www.who.int/mediacentre/news/releases/2016/nigeria-polio/en/|website=WHO|access-date=15 August 2016|date=11 August 2016|url-status=live|archive-url=https://web.archive.org/web/20160815045938/http://www.who.int/mediacentre/news/releases/2016/nigeria-polio/en/|archive-date=15 August 2016}}</ref>

Africa was declared free of wild polio in August 2020, although cases of circulating vaccine-derived poliovirus type 2 continue to appear in several countries.<ref>{{cite journal |last=Guglielmi |first=Giorgia |date=2020-08-28 |title=Africa declared free from wild polio — but vaccine-derived strains remain |url=https://www.nature.com/articles/d41586-020-02501-3 |journal=Nature |doi=10.1038/d41586-020-02501-3 |pmid=32860027 |s2cid=221365928 |access-date=1 July 2022 |archive-date=1 July 2022 |archive-url=https://web.archive.org/web/20220701110900/https://www.nature.com/articles/d41586-020-02501-3 |url-status=live}}</ref>

A single case of wild polio that was detected in [[Malawi]] in February 2022, and another in [[Mozambique]] in May 2022 were both of a strain imported from Pakistan and do not affect the African region's wild poliovirus-free certification status.<ref>{{cite web |title=Malawi declares polio outbreak |url=https://www.afro.who.int/news/malawi-declares-polio-outbreak |access-date=2022-06-29 |website=WHO {{!}} Regional Office for Africa |archive-date=16 June 2022 |archive-url=https://web.archive.org/web/20220616195336/https://www.afro.who.int/news/malawi-declares-polio-outbreak |url-status=live}}</ref><ref>{{cite web |date=2022-05-18 |title=First polio outbreak in 30 years declared in Mozambique |url=https://news.un.org/en/story/2022/05/1118502 |access-date=2022-07-01 |website=UN News |archive-date=1 July 2022 |archive-url=https://web.archive.org/web/20220701110841/https://news.un.org/en/story/2022/05/1118502 |url-status=live}}</ref>