Infection beyond doubt that certain diseases are caused by infectious agents, and developed a vaccine for rabies. Robert Koch, provided the study of infectious diseases with a scientific basis known as Koch's postulates. Edward Jenner, Jonas Salk and Albert Sabin developed effective vaccines for smallpox and polio, which would later result in the eradication and near-eradication of these diseases, respectively. Alexander Fleming discovered the world's first antibiotic, Penicillin, which Florey and Chain then developed. Gerhard Domagk developed sulphonamides, the first broad spectrum synthetic antibacterial drugs. The medical treatment of infectious diseases falls into the medical field of Infectious Disease and in
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