Two polio vaccinators -- a mother and a daughter -- were shot dead on Thursday by unidentified men on motorcycles in Pakistan's Quetta city. Quetta police spokesperson Abdul Rashid told Efe news that unidentified assailants shot the two women in the head after they had separated from the security team assigned to protect them during a vaccination campaign in the Shalkot area. It was an attack on the vaccination campaign Rashid said. The large-scale anti-polio campaign began on Monday aiming to immunise 38 million children nationwide. Here's why you should get polio vaccination even though polio is eradicated in India.