Which U.S. President is thought to have had polio?
Polio vaccine The results of the field trial were announced 12 April 1955 (the tenth anniversary of the death of President Franklin D. Roosevelt, whose paralytic illness was generally believed to have been caused by polio). The Salk vaccine had been 60–70% effective against PV1 (poliovirus type 1), over 90% effective against PV2 and PV3, and 94% effective against the development of bulbar polio. Soon after Salk's vaccine was licensed in 1955, children's vaccination campaigns were launched. In the U.S, following a mass immunization campaign promoted by the March of Dimes, the annual number of polio cases fell from 35,000 in 1953
Polio vaccine vaccinated children had died in both studies; no researchers dared attempt a polio vaccine for another 20 years. Professor John Kolmer, MD (1886–1962), of Temple University in Philadelphia, presented his findings first. He had developed an attenuated poliovirus vaccine, which he tested in about 10,000 children across much of the United States and Canada. Five of these children died of polio and 10 more were paralyzed, usually in the arm where the vaccine was injected, and frequently affecting children in towns where no polio outbreak had occurred. He had no control group, but asserted that many more children would have