Why 40,000 Karachi families refused polio vaccine

Forty thousand Karachi families refused polio vaccines this year. In a city where the virus circulates in every district, these denials represent the gap between Pakistan’s impressive polio infrastructure and its inability to close the last mile of eradication.

Pakistan has reduced polio cases by more than 99.6 percent since 1994—from 20,000 annual cases to just 30 this year. It has built one of the most extensive surveillance systems in the world: 127 environmental sampling sites, 12,500 reference sites and campaigns targeting 45 million children. Two of the world’s three strains of the polio virus have been eradicated.

But Pakistan and Afghanistan remain the only countries where polio is still circulating. And in 2024, the WPV1 strain resurfaced in 90 regions, forcing authorities to review their approach with a “2-4-6 roadmap” under the National Emergency Action Plan.

“The last mile is really very difficult to achieve,” said Dr Azra Pechuho, Sindh’s minister of health and population welfare, speaking at the Aga Khan University on Friday. “It’s the little pockets that we’re missing as the number of infected children goes down.” A two-hour event brought together the top names in polio from the WHO, the Sindh government, the federal government and AKU.

The environmental samples confirm what health officials already know: the virus remains in underserved communities that vaccination campaigns struggle to reach. Every district in Sindh shows ongoing transmission.

The 42,000 vaccine rejections across Sindh – 40,000 of them in Karachi – reflect what Dr Azra calls “vaccination fatigue”. But Dr Sebastian Taylor of the Polio Eradication Technical Advisory Group warned against assuming families are refusing because of too many vaccines. Many refusals stem from a lack of knowledge rather than vaccine overload, he said.

The WHO says authorities have narrowed the gap, reducing missing children from 1.48 million to 1.13 million. But low routine vaccination coverage, vaccine hesitancy and population movement continue to leave spaces where the virus survives.

South Khyber Pakhtunkhwa presents the most urgent challenge. “That’s where we need to do something very fast and very hard,” said Professor Shahnaz Ibrahim, chairman of the National Certification Committee, which determines each year whether Pakistan qualifies as polio-free.

The certification process requires three consecutive years with no cases and no environmental detection of the virus — and Pakistan cannot achieve this alone. “It has to be both Pakistan and Afghanistan as a unit,” Professor Ibrahim explained.

The Prime Minister’s Focal Person for Polio Eradication, Ayesha Farooq, noted that the genetic diversity of WPV1 is being “compressed more and more,” meaning less chance of new strains emerging. Dr Azra said eradication remains possible if Pakistan maintains focus during the coming period of low transmission.

“For students today, you don’t need to study smallpox. It’s history,” said Aziz Memon, National President of the Pakistan PolioPlus Committee. “Let’s put polio in the history books.”