Muhammed Muheisen, Associated Press
A Pakistani youth, who was displaced with his family from Pakistan's tribal region of Mohmand Agency due to fighting between the Taliban and the army, sleeps on the ground near his family's makeshift home on the outskirts of Islamabad, Pakistan, early Friday, Oct. 3, 2014.

ISLAMABAD — Pakistan has registered seven new polio cases, raising the number of those affected by the crippling disease this year to 194 and edging closer to the nation's own record number of 199 in 2001, a senior health official said Friday.

All of the new cases were from the North Waziristan tribal region bordering Afghanistan, where it has been impossible to launch anti-polio campaigns because of threats from militants, said Rana Mohammad Safdar from the National Institute of Health in Islamabad.

"We are concerned over it," Safdar told The Associated Press. "Lab tests two days ago confirmed these new cases."

Pakistan is one of only three countries where polio is 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, who have banned immunizations and attacked polio vaccination teams across Pakistan. Militants accuse polio workers of acting as spies for the United States and claim the vaccine makes boys sterile.

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

The militants' push against vaccination grew after it was revealed that a Pakistani doctor, Shakil Afridi, offered a program of hepatitis vaccinations in the northwestern city of Abbottabad. The program was a cover for his CIA-backed effort to obtain DNA samples from children at a local compound where Osama bin Laden was later killed during a 2011 raid by U.S. Navy SEALs.

Afridi was later convicted and sentenced by a Pakistani court to 33 years in prison for treason. The sentence was later overturned and the case is now facing retrial.

This week, Pakistan again launched another anti-polio drive in an attempt to get all of Pakistan's 34 million children vaccinated, Safdar said.

He added that polio workers were also trying to reach children who had migrated to the northwestern city of Bannu from North Waziristan in June when Pakistan's military launched a much-awaited operation in the country's troubled tribal region to eliminate local and foreign militants. It displaced over 800,000 people.