Paramilitary and police support was provided for the health workers, as polio vaccinations were resumed discreetly in the Khyber Pakhtunkhwa province after recent attacks on workers, officials said on Friday.
UN agencies suspended work on a nationwide campaign to inoculate children against the highly infectious disease after nine health workers were murdered in a string of attacks in the northwest and Karachi in December.
On Tuesday, six women and a man working for a charity involved in polio vaccinations were shot dead in the northwestern district of Swabi.
A senior government official said that instead of pressing another nationwide campaign, authorities had decided to inoculate children in phases, in a low key manner with adequate security arrangements.
Doctor Janbaz Afridi, head of polio eradication in Khyber Pakhtunkhwa, said that to ensure security, campaigns would be carried out in phases and separately in different districts.
“We had to launch a campaign from January 14, but were not given security clearance, so we reviewed the schedule and modified our policy to do it in phases starting from high-risk districts,” Afridi told AFP.
“The inoculation teams can now go into selected areas with adequate security at any suitable time instead of a province-wide campaign,” he added.
Polio cases in Pakistan have risen sharply in recent years, hitting 198 in 2011 – the highest figure for more than a decade and the most of any country in the world last year, according to the World Health Organization.
Rumours about the vaccine being a plot to sterilise Muslims have long dogged efforts to tackle the disease in Pakistan.
Suspicion of vaccination programmes intensified after the jailing of a doctor who helped the CIA find Osama bin Laden in 2011 using a hepatitis campaign.
Last year the Taliban and Pakistani warlord Mullah Nazir, who was killed in a US drone strike on Wednesday, banned polio vaccinations in the tribal region of Waziristan, condemning the campaign as a cover for espionage.
In some parts of the northwest, women health workers now refuse to take part in polio vaccinations out of fear, officials said.
“Female health workers are not participating in this campaign but we have enlisted government employees, school teachers and volunteers from civil society,” said administration official Javed Khan Marwat in the city of Peshawar.
He said motorcycles would be banned in an effort to avert drive-by shootings in areas where the campaign will try to vaccinate 777,000 children from Saturday.
In the northwestern district of Charsada, senior administration official Zafar Ali Shah said that women health workers have refused to administer polio drops in “20 high-risk areas”.
“Small teams of four to five health workers with two policemen and two FC (paramilitary Frontier Corps) personnel will give polio drops,” Shah said.