The area — North and South Waziristan — is too dangerous for health workers to venture. Islamic militants, many with ties to al-Qaida, banned polio vaccinations there in 2012 to press their demand that the United States end its use of drones to target their hideouts.
Militants have also created suspicion among ultraconservative parents in Pakistan's deeply religious northwest, saying the polio vaccine will make their children impotent. The vaccine, they claim, is a ploy by the West to limit the world's Muslim population.
But health workers and militants alike agree the biggest setback was the highly publicized use of a Pakistani doctor and a vaccination ruse to ferret out al-Qaida chief Osama bin Laden in May 2011. Dr. Shakil Afridi is in jail in Pakistan for his role in the CIA operation that uncovered bin Laden's hideout in the northwestern city of Abbottabad, 60 miles (100 kilometers) from the capital, Islamabad.
While Afridi never got DNA samples from the bin Laden family, his involvement in the covert operation that led to bin Laden's death caused residents to look with suspicion on many vaccination programs. Devastating for the polio campaign were the images of Afridi standing beside a banner promoting polio vaccinations as television commentators told of his collusion with the CIA.
"We have deep sensitivity about the polio vaccination after the martyrdom of the great mujahed and leader of Muslims, Sheikh Osama bin Laden," Taliban spokesman Ehsanullah Ehsan told The Associated Press. "We still have strong suspicions that the vaccination campaign could be used again and again to spy on Muslims and the mujahedeen."
The ruse also turned the polio campaign violent. The first attack against a health worker occurred in June 2012, said Dr. Imtiaz Ali Shah, the KPK provincial government polio campaign coordinator. Since then, 40 people participating in vaccination campaigns have been killed in Pakistan and another 39 injured, according to UNICEF figures.
"Before 2011, we never saw health workers being attacked," he said. "Now there are parts of Pakistan that are so volatile that vaccinators can't go there."
Mohammad Wasil's 19-year-old son, Hilal, was killed by militants as he vaccinated children in rural northwest Pakistan. Sitting on a bed made of rope in his village, where women are rarely seen without the all-enveloping burqa, Wasil said his son volunteered because he loved children and wanted to earn money for his education.
Still, there have been small gains. In 2012, new polio cases in northwest Pakistan were found in 13 districts; a year later, that was reduced to six districts. But the virus is stubborn, and in the provincial capital of Peshawar, it keeps reappearing, forcing tens of thousands of children to be revaccinated because they may not have built up enough immunity.
"That makes everyone suspicious," said Al-Dhayi, the UNICEF spokeswoman. "They wonder whether there was something wrong with the vaccine or with the new vaccination being administered."
It has been impossible to eradicate the polio virus from Peshawar, says Shah, because people from the heavily infected tribal regions that are off limits for health workers arrive daily in the city, bringing with them a fresh outbreak.
The tribal regions "are producing so many cases and the (tribal people) travel regularly," he said.
Al-Dhayi said some of the new polio cases showing up elsewhere in Pakistan have also been tracked to Peshawar and other areas of northwest KPK province.
In the meantime, UNICEF is trying to get Pakistan's senior Islamic clergy to support the polio campaign, with some success, according to Al-Dhayi. Among those recruited is the so-called father of Afghanistan's Taliban movement, Maulana Sami-ul-Haq.
"The effort is really intensive and proving positive," she said, but the clock is ticking. "Pakistan is the worst of the three (polio-endemic countries) in terms of the number of cases and the complexity."
Kathy Gannon is AP Special Regional Correspondent for Pakistan and Afghanistan and can be followed at www.twitter.com/kathygannon
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