Polio Polio is a contagious disease affecting humans and some primates. Three closely related viruses cause polio. In serious cases Polio attacks the spinal cord and brain stem and eventually causes paralysis. In Polio the muscular, brain and nervous systems are affected, and is spread by contaminated food, water, hands and eating utensils. Polio was one of the most feared diseases in the 20th century. The connection between the neurological symptoms of Polio and the …showed first 75 words of 550 total…

…showed last 75 words of 550 total…vaccine. By 1950, a practical vaccination program was beginning to take shape under the direction of Jonas Salk, who headed the development of an injectable vaccine. In 1954 they began using the Salk vaccine to inoculate all children and the Polio rate drastically decreased. Salk's vaccine provided only temporary immunity; it required booster shots to be administered at yearly intervals. Albert Sabin developed an oral vaccine and is still used to eradicate Polio in Africa and Asia.