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
Jonas Salk human side of nature, if you like, and I continue to be interested in that." After City College, Salk enrolled in New York University to study medicine. According to Oshinsky, NYU based its modest reputation on famous alumni, such as Walter Reed, who helped conquer yellow fever. Tuition was "comparatively low, better still, it did not discriminate against Jews, ... while most of the surrounding medical schools—Cornell, Columbia, University of Pennsylvania, and Yale—had rigid quotas in place." Yale, for example, accepted 76 applicants, in 1935, out of a pool of 501. Although 200 of the applicants were Jewish, only five