Two polio vaccines are used throughout the world to combat polio. The first was invented by Jonas Salk, and first tested in 1952 and announced to the world by Salk on March 26, 1953. It consists of an injected dose of killed polio virus. Albert Sabin[?] produced a cheaper and more effective oral polio vaccine in 1962.
... 45 to 64, and 14.1% who are 65 years of age or older. The median age is 28 years. For every 100 females there are 82.8 males. For every 100 females age 18 and over, ...