Pak polio vaccine teams on edge after fatal attacks

Polio workers across Pakistan were told to remain vigilant on Thursday after multiple attacks on vaccination teams killed at least three people this week during an ongoing push to eradicate the disease from the restive country.

The latest victim, a polio worker, was shot in southwestern Balochistan province on Thursday morning, following separate attacks targeting health workers in the country's northwest earlier this week that left two police officers dead.

"The attack has taken place in a remote area, and we have received reports that one female polio worker has been killed," Attaullah Shah, a district police chief, told AFP, saying a second health worker was also critically injured in the attack.

The injured worker was later rushed to a nearby clinic before being sent to hospital in the provincial capital of Quetta for additional treatment.

There was no immediate claim of responsibility for the incident but militants -- including the Pakistani Taliban -- have attacked polio workers in the past, killing more than 100 people since December 2012.

Security officials in Pakistan told AFP that authorities have instructed polio teams to remain "vigilant" amid the violence.

The attacks come days after more than 25,000 children were rushed to hospitals in northwestern Pakistan after rumours spread some had suffered reactions to a polio vaccine.

The panic came as health workers were carrying out a three-day vaccination campaign in northwestern Khyber Pakhtunkhwa province, with authorities saying dozens of polio workers have been beaten or harassed.

Ongoing suspicion of the polio vaccine in Pakistan has been compounded recently by anti-vaccination videos circulating on social media.

Islamist opposition to all forms of inoculation grew after the CIA organised a fake vaccination drive to help track down Al-Qaeda leader Osama Bin Laden in the Pakistani garrison town of Abbottabad. He was killed there by US forces in 2011.

Some Taliban and ultra-conservative religious leaders have also been known to spread rumours that vaccines contain ingredients forbidden in Islam, such as pork derivatives, or that can cause infertility as part of a Western plot to reduce the population.

"We have a communication challenge, it's a mistrust issue," said Babar Atta, who is helping oversee the country's vaccination drive.

Atta said at least 260,000 health workers are involved in the campaign with some 150,000 police escorting the teams.

However, Atta added that hundreds of thousands of children were likely to go unvaccinated.

"There is a serious lack of trust among the parents," he said.

Polio is endemic in only three countries in the world -- Pakistan, Afghanistan and Nigeria -- although a relatively rare strain was also detected in Papua New Guinea at the end of last year.

Polio is a highly contagious disease caused by a virus that invades the nervous system and can cause total paralysis within hours. It mainly affects children under the age of five.