Islamabad , Pakistan ( CNN ) Police have arrested more than 500 parents in and around the northwestern Pakistani city of Peshawar for not allowing their children to get the polio vaccine , an official said Tuesday . Peshawar Deputy Commissioner Riaz Khan Mehsud told CNN that the 513 arrests took place Monday and Tuesday as part of a government campaign to administer polio vaccines in parts of Pakistan 's Khyber Pakhtunkhwa province . Those arrested will be released on bail if they sign an affidavit stating that they will let their children get vaccinated , according to the deputy commissioner . Pakistan 's vaccination rate is inordinately low for a number of reasons , including attacks on medical workers , the displacement of people due to ongoing military operations and a lack of trust by some families . Whatever the reason , the fact that a large number of children are not immunized is having an impact . Such vaccines are credited with wiping out polio in most parts of the world . But Pakistan is an exception , according to the Global Polio Eradication Initiative , a public-private partnership that includes the World Health Organization and United Nations Children 's Fund ( UNICEF ) . The South Asian nation leads all others in new polio cases in recent years , and has nine of this year 's 10 reported cases . In 2014 , Pakistan had 327 cases . The next closest country was Nigeria , with 36 cases . Authorities in Khyber Pakhtunkhwa province hope to ensure that 2.7 million children there get vaccine drops . They 've learned about more than 13,000 cases in which parents have not done so since a provincial campaign began two weeks ago , Mehsud said . Dr. Bilal Ahmad , a UNICEF team leader based in Pakistan , called authorities ' unprecedented move a last-ditch effort to clear polio from `` cluster '' zones where large numbers of families have refused to get their children vaccinated . `` First the workers ( try to ) convince them , then their supervisors , then senior members of the community , '' Ahmad said . `` ( This government action ) is the final step in eradicating this issue . '' Polio is a highly infectious viral disease that primarily affects young children , sometimes leading to paralysis and death . The virus is easily preventable through immunization , but there 's no cure once it is contracted . It went from being a health issue to a security issue after U.S. intelligence officials used a vaccination program to help in their hunt for Osama bin Laden in 2011 . Under cover of the program , the CIA sought to collect DNA samples from relatives of the al Qaeda leader to verify his presence in a compound in Abbottabad , Pakistan . CIA policy : Wo n't use vaccination programs as part of operations . Those administering the vaccines have become targets , with the National Emergency Operations Center reporting that more than 70 medical workers have been killed in attacks since December 2012 . And in June 2012 , Pakistani Taliban commander Hafiz Gul Bahadur announced that polio vaccines would be banned in another Pakistani province -- North Waziristan -- because of drone strikes there . Bahadur called the strikes `` worse than polio . '' CNN 's Sophia Saifi reported from Islamabad , and CNN 's Greg Botelho wrote this report from Atlanta .
Official : - Le développement de la technologie des smartphones pliables est Pakistan has more new polio cases than any other country . Militants have targeted health workers administering vaccines for years .