How the polio vaccine virus occasionally becomes dangerous

(Michigan Medicine - University of Michigan) The polio vaccines, developed by Jonas Salk and Albert Sabin in the mid-1950s, heralded the elimination of polio from the U.S., saving countless children from sudden paralysis and death. In the developing world, however, outbreaks of poliovirus still occur sporadically, an ironic consequence of the polio vaccine itself. A new genetic study of the vaccine poliovirus reveals how this happens in real time.