Wild polio has been pushed back by more than 99% since 1988 and now survives only in Afghanistan and Pakistan, but transmission there persists, vaccine-derived outbreaks continue in dozens of countries, and the programme faces a funding shortfall in its final stretch.
Updated October 15, 2026. Written from the sources listed below, not independently peer-reviewed.
In 1988, polio paralysed an estimated 350,000 people a year in more than 125 countries. How many wild poliovirus cases were reported worldwide in 2025?
52
Wild poliovirus cases
Type 1 cases in 2025: 31 in Pakistan and 21 in Afghanistan. Four more were reported in 2026 by the time of the committee statement published in August 2026.
Data year 2025. Source: World Health Organization, 2026
238
Vaccine-derived polio cases
Circulating vaccine-derived poliovirus cases reported in 30 countries in 2025, plus 247 positive sewage samples. Nigeria alone had 66 type 2 cases.
Data year 2025. Source: World Health Organization, 2026
74%
Infants with two or more IPV doses
WHO/UNICEF estimate for 2025. 86% received at least the first dose of injected inactivated polio vaccine.
Data year 2025. Source: World Health Organization, 2026
World averages of WHO/UNICEF estimates of third-dose polio vaccine coverage (oral or inactivated vaccine) as published in World Bank Open Data; selected reported years only. 2025 values were not yet in this dataset in October 2026. Coverage rose steeply in the 1980s, plateaued in the 1990s and has not yet returned to its 2019 level after pandemic disruption. Coverage alone does not show the extra doses given in mass campaigns.
After missing earlier goals, GPEI extended its strategy in 2024 to the end of 2027 for wild poliovirus and the end of 2029 for type 2 vaccine-derived poliovirus. Its operational targets are to interrupt endemic wild transmission in 2026 and stop type 2 outbreaks by 2028. With wild cases and 74 positive sewage samples reported in both endemic countries in the first months of 2026, and 13 type 2 outbreak lineages from 2025 still detected by the end of April, both milestones remain uncertain.
Wild poliovirus is endemic only in Afghanistan and Pakistan. Pakistan reported 651 positive sewage samples in 2025 and Afghanistan 94, showing much wider circulation than the case counts alone suggest.
Source: World Health Organization, 2026In Afghanistan, vaccination teams have not gone house to house since October 2024 for security reasons. Campaigns from fixed sites often miss children, especially the youngest.
Source: World Health Organization, 2026Nigeria reported 66 cases of type 2 vaccine-derived polio in 2025, about 30% of the global total for that type.
Source: World Health Organization, 2026WHO warns that countries with weak health systems, low immunization coverage and travel or trade links to affected areas are most at risk of importing the virus.
Source: World Health Organization, 2026Each country is shaded by its latest available value, so you can see where the gap is widest. Hover or tap a country, search for one, or open the full table.
Loading country values…
Values in % of one-year-old children.
Shown as 100 minus WHO/UNICEF estimated coverage with the third dose of polio vaccine (oral or inactivated). Latest year available per country: almost all values are for 2024 (Nicaragua 2023); the 2025 estimates had not yet reached World Bank Open Data. Routine coverage does not include doses given in mass campaigns, which matter greatly in Afghanistan, Pakistan and outbreak countries. North Korea is reported at 0% coverage, which reflects missing data and supply disruption rather than a measured rate.
Source: WHO and UNICEF estimates of national immunization coverage, via World Bank Open Data. Latest year available per country; years differ.
Values load from World Bank Open Data. Simplified Natural Earth borders; they imply no position on disputed territories.
Instead of one “percent solved” score, DO GOOD rates three separate dimensions. A problem can have mature solutions that still reach too few people. These ratings are an editorial reading of the sources on this page, not a measured index.
Has the situation improved in the real world?
HighWild poliovirus cases have fallen by more than 99% since 1988 and the wild virus is endemic in only two countries, but 52 wild cases and 238 vaccine-derived cases in 2025 show the job is unfinished.
How mature and validated are the available solutions?
HighOral and inactivated polio vaccines are long proven, and the more genetically stable novel oral vaccine against type 2 has been given more than 2 billion times since 2021. The remaining obstacles are mainly about reaching every child.
How widely are effective solutions actually used?
ModerateCampaigns aim to reach about 370 million children a year, yet only 74% of infants received two or more IPV doses in 2025, and hundreds of thousands of children in insecure areas of Pakistan and Somalia are reported unreached.
Laboratory-confirmed case reporting and sewage testing give an unusually detailed picture, but the emergency committee has raised concerns about surveillance sensitivity in parts of Pakistan, and counts rise as results come in: GPEI cited 39 wild cases for 2025 in December 2025, against 52 in the final tally.
Only four wild cases were reported in early 2026 and no new type 2 outbreak lineages had emerged by the end of April, but sewage samples remain positive in both endemic countries and the committee called the 2025 rise in type 1 and type 3 vaccine-derived outbreaks a concern.
Polio is a highly infectious viral disease that mainly affects children under five. About one infection in 200 leads to irreversible paralysis, and 5–10% of those paralysed die when their breathing muscles stop working. Since the global eradication effort began in 1988, cases of wild poliovirus have fallen by more than 99%, from an estimated 350,000 a year in over 125 countries. WHO credits vaccination with more than 20 million people who can walk today and about 1.5 million childhood deaths prevented. Wild poliovirus type 1 is now endemic only in Afghanistan and Pakistan, which together reported 52 cases in 2025 and 747 positive sewage samples, two of them found in Germany.
The final stretch is the hardest. In parts of both endemic countries, insecurity and access limits leave children unvaccinated: in southern Khyber Pakhtunkhwa in Pakistan an estimated 250,000 children were reported unreached in recent campaigns, and Afghanistan has not run house-to-house campaigns since October 2024. At the same time, where too few children are immunised, the weakened virus in oral polio vaccine can circulate for long periods and regain the ability to paralyse. These circulating vaccine-derived outbreaks caused 238 cases in 30 countries in 2025. As long as any child remains infected, children everywhere are at risk, and WHO continues to treat the international spread of poliovirus as a public health emergency of international concern. The programme reports a funding shortfall of nearly 30%.
The Global Polio Eradication Initiative (GPEI), a partnership that includes WHO, tracks the virus through laboratory-confirmed cases and sewage testing, and judges protection by vaccination coverage:
Wild poliovirus cases (WPV1)
Children with sudden paralysis are tested, and cases are counted when wild poliovirus type 1 is confirmed in a laboratory. Because only about one infection in 200 causes paralysis, each case signals many more silent infections.
Circulating vaccine-derived poliovirus (cVDPV)
Cases and outbreaks caused by strains that originated from the weakened virus in oral polio vaccine and spread in under-immunised communities. They are counted by type (1, 2 or 3) and by new 'emergences', independent outbreaks that each arose separately.
Environmental surveillance
Regular testing of sewage samples detects poliovirus even when no one is paralysed. Positive samples show where the virus is still circulating, including in countries with no cases.
Vaccination coverage
The share of infants who receive three doses of polio vaccine (Pol3) and the doses of inactivated polio vaccine (IPV) given by injection, estimated each year by WHO and UNICEF. Campaign quality is checked separately with surveys of children after vaccination rounds.
What works
Drops given by mouth are cheap, easy to deliver without trained injectors and block the virus in the gut, which stops it spreading. Repeated door-to-door campaigns drove wild polio out of all but two countries.
Limits
Campaigns must reach almost every child, which is hard in insecure or inaccessible areas. Where coverage is too low, the weakened vaccine virus can circulate and turn into vaccine-derived poliovirus.
What works
Injected IPV protects individuals against paralysis from all types without any risk of vaccine-derived virus. In 2025, 86% of infants received a first dose and 74% two or more doses.
Limits
IPV is given by injection, costs more, and protects mainly against paralysis rather than gut infection, so it cannot stop transmission on its own. Some countries have still not added the second dose to their schedules.
What works
This modified vaccine is more genetically stable than the earlier type 2 oral vaccine and is used to stop type 2 vaccine-derived outbreaks. More than 2 billion doses have been given since 2021, drawn from a global stockpile.
Limits
Its risk is lower but not zero: 42 new type 2 outbreak lineages have been linked to nOPV2, and it only works when campaigns reach enough children quickly.
What works
Testing every child with sudden paralysis, together with routine sewage sampling, detects the virus where it circulates silently, as in Germany's wastewater in October 2025, and lets countries respond quickly.
Limits
Surveillance quality varies between districts, and the committee has asked GPEI to monitor it more closely in priority countries. Sewage testing is not available everywhere.
What works
Under the International Health Regulations, countries with local transmission are asked to give residents and long-term visitors a dose of polio vaccine between four weeks and 12 months before international travel. Afghanistan and Pakistan, treated as one epidemiological bloc, run mostly synchronised campaigns.
Limits
The measures depend on national enforcement and do not fix the gaps in immunity that let outbreaks take hold.
Promising, but not proven at scale. The stage shows how far each approach has come; it is not a recommendation.
Following the approach used for nOPV2, more genetically stable oral vaccines against types 1 and 3 are being developed to respond to rising type 1 and 3 vaccine-derived outbreaks without seeding new ones. They are still in clinical development.
Giving a small fraction of the standard IPV dose into the skin stretches limited vaccine supply and is being used in some campaigns in hard-to-reach areas. Delivering it needs trained staff and suitable devices, and it is not yet a routine tool everywhere.
Combining polio vaccination with measles, nutrition and other basic services aims to reach communities more efficiently and build trust where repeated polio-only visits meet fatigue. Evidence on whether this improves polio coverage is still limited.
Implementation gap
In southern Khyber Pakhtunkhwa an estimated 250,000 children were reported unreached because of insecurity, and Afghanistan has used only site-to-site campaigns since October 2024, which often miss younger children.
Implementation gap
GPEI's 2022–2029 strategy needs US$6.9 billion. Pledges in December 2025 reduced the remaining gap to US$440 million, yet in 2026 the emergency committee still described a shortfall of nearly 30% that threatens all parts of the programme.
Implementation gap
Vaccine-derived outbreaks arise where too few children are protected. The emergency committee points to continued low routine and IPV coverage in several countries as a driver of spread.
Technology gap
Type 1 and type 3 vaccine-derived outbreaks rose in 2025, with type 1 detected in countries including Algeria, Djibouti and Israel, and no tailored novel vaccine against these types is yet approved, so responses still rely on the older oral vaccine.
Knowledge gap
Concerns about how sensitive surveillance is in the northern corridor, which includes Peshawar, mean the virus could circulate longer than detected. Gaps matter most in insecure areas, where they are hardest to close.
Coordination gap
The virus moves between Afghanistan and Pakistan along shared population corridors and has been found in sewage as far away as Germany, so progress depends on synchronised campaigns and data sharing across borders.
Unresolved questions, not vetted breakthroughs. Answering any of them would change what is possible.
Which combination of campaign design, community involvement, integrated services and negotiation with local authorities can reliably vaccinate children in insecure areas where house-to-house visits are not possible?
How long can wild poliovirus persist without detected cases, and how many clean months of case and sewage surveillance are needed before transmission can be declared interrupted with confidence?
After wild poliovirus is gone, how can countries stop using oral vaccines without leaving immunity gaps that let vaccine-derived strains spread, and what role should IPV and novel oral vaccines play?
Which campaigns and surveillance activities can be scaled back with the least risk, and how will reductions in polio funding affect wider health services that rely on polio staff and laboratories?
Make sure your children have all routine polio doses, and check with a doctor before travelling to countries with polio outbreaks whether you need a booster.
Rotary clubs, UNICEF and other partners of the Global Polio Eradication Initiative raise money for vaccination campaigns. Check how organisations report their spending and results before you give.
Polio vaccine campaigns are often targeted by rumours. When the subject comes up, point people to health authorities rather than repeating unverified claims.
Much of the polio programme depends on government donors. Telling elected representatives that you support finishing the job is one of the few ways to influence that funding.
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World Health Organization (25 August 2026), published 2026
Committee meeting of 14 May 2026. Source of 2025 and 2026 wild and vaccine-derived case counts, positive sewage samples, the Germany detection, Nigeria's share of type 2 cases, nOPV2 doses and linked emergences, the 2026 and 2028 targets, access problems in Pakistan, Afghanistan and Somalia, surveillance concerns and the shortfall of nearly 30%.
Global Polio Eradication Initiative (8 December 2025), published 2025
Pledging moment for the 2022–2029 strategy. Source of the US$1.9 billion pledged, the remaining US$440 million gap, the target of reaching 370 million children a year, the over 99% decline since 1988 and the 125 formerly affected countries.
Global Polio Eradication Initiative (17 October 2024), published 2024
Extension of the strategy to 2029. Source of the US$6.9 billion budget for 2022–2029 and the new timelines (end of 2027 for wild poliovirus, end of 2029 for type 2 vaccine-derived poliovirus).
World Health Organization (2 April 2025), published 2025
Background on the disease and the eradication effort. Source of the one-in-200 paralysis rate, 5–10% fatality among those paralysed, the 350,000 cases in 1988, 20 million people spared paralysis and 1.5 million childhood deaths prevented.
World Health Organization (15 July 2026), published 2026
Summary of the 2025 WHO/UNICEF coverage estimates. Source of first-dose (86%) and two-or-more-dose (74%) IPV coverage and the description of countries most at risk of importation.
World Bank Open Data, based on WHO and UNICEF estimates (accessed 15 October 2026), published 2026
World aggregate of third-dose polio vaccine coverage, used for the trend chart (1985, 1990, 2000, 2019 and 2024). The 2025 value was not yet included.