When a case of polio was discovered in an unvaccinated man in Rockland County, New York, last month, many people had a similar thought: “Didn’t we take care of polio?” Before the Salk and Sabin polio vaccines were available in 1955 and 1963, respectively, polio outbreaks caused more than 15,000 cases of paralysis in the United States each year before 1955, according to the Centers for Disease Control (CDC). By the 1970s, that number was fewer than 10. Since 1979, no cases of polio caused by wild poliovirus have originated in the United States. View more