Civil strife in countries such as Pakistan and Syria is thwarting efforts to combat the polio virus, which has spread and become an international public health emergency, according to the World Health Organization.

“It’s really attributed to two things. One is the spread out of Pakistan through the intense transmission there because of the suspension of the vaccine in one area,” Dr. Bruce Aylward, a Canadian physician and WHO’s assistant director-general of polio, told CBC News. “And then combined with an increase in vulnerability of some highly unstable areas like Syria where it’s been able to get another foothold.”

The agency described current polio outbreaks across at least 10 countries in Asia, Africa and the Middle East as an "extraordinary event" that required a co-ordinated international response. It identified Pakistan, Syria and Cameroon as having allowed the virus to spread beyond their borders, and recommended that those three governments require citizens to obtain a certificate proving they have been vaccinated for polio before travelling abroad.

In February, the WHO found that polio had also returned to Iraq, where it spread from neighbouring Syria. It is also circulating in Afghanistan (where it spread from Pakistan) and Equatorial Guinea (from neighbouring Cameroon) as well as Nigeria, Ethiopia, Somalia and Kenya.

But the biggest concern is Pakistan, which recorded 59 of the 74 cases reported. While Pakistan had a good eradication program, the volatile area of North Waziristan, which borders Afghanistan, has banned all polio vaccinations.

Taliban placed ban on vaccinations

Two years ago, the Taliban placed a ban in the area, saying it would stay in place until the U.S. military ended its drone strikes.

"Almost every resident of North Waziristan has become a mental patient because of the drone strikes, which are worse than polio," the Taliban said in a statement two years ago, according to CNN. "On one hand, the U.S. spends millions of dollars to eliminate polio, while on the other hand it kills hundreds with the help of its slave, Pakistan."

Many in that area have become suspicious of polio workers who go door to door vaccinating children, believing that logistical information is being gathered for drone strikes.

Dozens of polio workers have been killed over the last two years in Pakistan, where militants accuse them of spying for the U.S. government. Those suspicions stem at least partly from the disclosure that the CIA used a Pakistani doctor to uncover Osama bin Laden's hideout by trying to get blood samples and DNA information from his family under the guise of a hepatitis vaccination program.

“A lot of this has been about rebuilding trust in this area and [saying] this has nothing to do with drones and we don’t control drones, this is about your kids,” Aylward said.

“The government hasn’t been able to renegotiate the restart of [vaccination], yet in North Waziristan they had a roaring outbreak, so you had intensive transmission that’s getting a lot of people and adults exposed.”

Outbreak in Syria

Polio has also re-emerged in Syria, where the civil war has hampered access to vaccinations. Before the war, polio vaccine coverage in the area was quite high, Dr. Mickey Chopra, UNICEF’s chief of health, told CBC News.

"As soon as you let your guard down, which is what has happened in Syria over the last 18 months of the civil war, and kids are not being vaccinated and they’ve been malnourished and vulnerable — then the virus comes rushing in.”

War can cause huge refugee problems, displacing thousands of people and making vaccinations much more challenging. But it doesn't necessarily mean the programs have to end. The continuation of such vaccinations during a conflict depends on the combatants and national governments giving it a priority, Chopra said.

"We’ve managed to eradicate polio even from places such as Sudan and other places where there is ongoing civil strife. Because there has been an agreement among the parties that giving vaccinations to children is a human right that they’ve allowed access."

Afghanistan, he said, is a great example where polio doctors have been able to reach agreements with local residents to vaccinate children.

"We do have experience of negotiating in times of war, so it’s not impossible, and that’s why what’s going on in Syria and other places is not acceptable. Both sides are not allowing sufficient access."