Why Does Transmission Remain a Concern?
The committee said transmission continued in both endemic countries through the most recent low-transmission season, from October 2025 through April 2026.
Although the overall number of wild poliovirus type 1 cases and positive environmental samples has declined, transmission has continued in important areas of Afghanistan and Pakistan.
The committee said programme and vaccination gaps remain in several high-risk locations, meaning progress toward eradication remains fragile.
What Is the Current Wild Polio Situation?
Afghanistan and Pakistan remain the world’s two countries where wild poliovirus type 1 is endemic.
Since the committee’s previous meeting in January 2026, 16 new WPV1 cases have been reported from the two countries, including 14 in Afghanistan and two in Pakistan.
So far in 2026, four WPV1 cases have been reported: three in Afghanistan and one in Pakistan.
WHO also reported 74 WPV1-positive environmental samples in 2026, with 17 detected in Afghanistan and 57 in Pakistan.
Where Is Polio Transmission Still Concentrated?
WHO identified three major areas of concern:
- South Region of Afghanistan
- South Khyber Pakhtunkhwa in Pakistan
- Karachi, Pakistan
The South Region of Afghanistan remains the area of greatest concern because of intense transmission and evidence of prolonged undetected circulation.
South Khyber Pakhtunkhwa faces security and operational challenges that make high-quality vaccination activities difficult.
Karachi also remains an important reservoir for poliovirus transmission, with widespread environmental surveillance positivity indicating continued local transmission.
What Is Happening in Afghanistan?
Afghanistan has continued vaccination campaigns, but WHO says significant challenges remain.
House-to-house vaccination campaigns have not been conducted since October 2024 because of security concerns.
Instead, vaccination teams have relied on a site-to-site strategy.
WHO said this approach can make it difficult to reach all children, particularly younger children. The committee also expressed concern about the limited participation of women as vaccination health workers, especially in southern Afghanistan.
What Is Happening in Pakistan?
Pakistan has continued vaccination campaigns and has maintained strong political commitment to polio eradication.
WHO noted encouraging signs in several areas, including Karachi, where environmental detections have declined and some vaccination-quality indicators have improved.
However, the committee said these gains remain fragile.
South Khyber Pakhtunkhwa continues to experience intense WPV1 transmission, while security and access problems have left many children unreached.
What About Vaccine-Derived Poliovirus?
The global polio situation also includes circulating vaccine-derived polioviruses, known as cVDPVs.
As of 30 April 2026, WHO reported 32 cVDPV cases and 27 positive environmental detections across 12 countries.
Of the 32 cases, 28 were cVDPV2, two were cVDPV3 and two were cVDPV1. All 27 positive environmental samples were cVDPV2.
Nigeria reported the highest number of cVDPV2 cases in 2025, with 66, and in 2026 to date, with 14. Nigeria also reported co-circulation of cVDPV2 and cVDPV3 in 2026.
Why Is Cross-Border Spread a Concern?
WHO highlighted continued population movement between Afghanistan and Pakistan as an important factor in the risk of cross-border transmission.
The committee said the two countries form a single epidemiological bloc for polio eradication and called for strong coordination at national and subnational levels, particularly in border areas.
WHO reported two WPV1-positive environmental samples in Germany in 2025. No further detections were reported there after the first half of October 2025.
Is the Global Polio Situation Getting Better?
There has been measurable progress.
WHO said the overall trajectory of WPV1 cases and environmental detections is declining, and several areas have shown improvements in vaccination and surveillance.
However, the committee warned that declining numbers alone do not mean eradication-level programme quality has been achieved.
Persistent transmission in important areas, immunity gaps and difficulties reaching children continue to create risks.
What Does WHO Say About a Pandemic Emergency?
WHO said amendments to the International Health Regulations that entered into force in September 2025 introduced a “pandemic emergency” designation. The designation is a higher level of global public-health alert in relation to a Public Health Emergency of International Concern.
What Is WHO Recommending?
WHO is calling for continued high-quality vaccination and surveillance efforts.
Afghanistan and Pakistan have been urged to maintain close coordination, particularly along their shared border.
The organization also wants vaccination programmes to reach children who have previously been missed and for surveillance systems to remain strong enough to detect transmission quickly.
What Happens Next?
WHO’s stated goals are to interrupt endemic WPV1 transmission in 2026 and to stop cVDPV2 outbreaks by 2028, followed by certification of WPV1 eradication and cVDPV2 elimination.
The immediate priorities include strengthening surveillance, improving routine and supplementary immunization, implementing programme-improvement recommendations and ensuring access to all children.
TwikUp Insight
WHO’s latest assessment shows that the global fight against polio is making progress but has not reached the finish line.
Wild poliovirus transmission is now geographically limited to Afghanistan and Pakistan, yet continued circulation in high-risk areas and gaps in vaccination coverage remain major obstacles.
The committee emphasized that sustained vaccination, surveillance and cross-border coordination will be essential to interrupt transmission.
