Pakistan has detected a record number of polio cases already this year, a senior government official said Saturday, as militants target vaccination teams and accuse doctors of being spies and sterilising boys.

With the confirmation of polio virus among eight more children from the north-west and south-western city of Quetta and port city of Karachi, Pakistan broke its 14-year-old record of highest cases in a year, said Rana Mohammad Safdar, a senior official at the National Institute of Health in Islamabad.

He said doctors discovered 202 cases from January to 3 October. The previous modern record was 199 cases in 2001.

“We are sad to announce that the number of polio cases is now all-time high in Pakistan,’” Safdar said.

Pakistan, Afghanistan and Nigeria are the only three countries in the world where polio remains endemic. The highly contagious virus is transmitted in unsanitary conditions but is easily fended off with a vaccine.

However, efforts to eradicate it are hampered by the Taliban, which has banned immunisations and attacked polio vaccination teams across Pakistan.

Militants stepped up attacks on polio workers after it was revealed that a Pakistani doctor, Shakil Afridi, offered a program of hepatitis vaccinations in the north-western city of Abbottabad as a front for his CIA-backed effort to obtain DNA samples from children at a local compound where Osama bin Laden lived.

The al-Qaida leader was killed in 2011.

About 60 polio workers or police escorting polio teams have been killed in Pakistan since 2012, Safdar said.

“New polio cases are surfacing because of those children who could not be immunised against the disease in tribal regions,” he said. “We were expecting this alarming increase in polio case.”

Safdar said Pakistan again launched a nationwide anti-polio drive this week in an attempt to get all Pakistan’s 34m children vaccinated.