Gunmen fired on two female health workers administering polio vaccines in northwest Pakistan on Tuesday , killing one and wounding the other . Pakistan is one of three countries in the world where polio has yet to be eradicated . The World Health Organization says that more than 100 million children are at risk from polio. Pakistanis have viewed polio vaccination campaigns with suspicion .
Pakistan is one of three countries in the world where polio has yet to be eradicated . The World Health Organization says that more than 100 million children are at risk from polio. Pakistanis have viewed polio vaccination campaigns with suspicion .