AdvertisementMutant Strains Of Polio Vaccine Now Cause More Paralysis Than Wild PolioJune 28, 2017Jason BeaubienfacebookEmailNurses give the oral polio vaccine to a Syrian child in a refugee camp in Turkey. The oral polio vaccine used throughout most of the developing world contains a form of the virus that has been weakened in the laboratory. But it's still a live virus. (Getty Images)