Cold War tensions and the polio vaccine polio vaccine. By the 1950, Jonas Salk had tested both live, attenuated polio vaccines and formaldehyde killed polio vaccines in monkeys and by 1952, began testing on humans. The killed vaccine was found to be effective, with proper filtration of the biological culture. A problem with this vaccine was the perception that to be adequately protected; a child had to get three Salk shots, properly spaced, and a recommended booster shot once a year, which was expensive. It should be noted however, that Jonas Salk, himself, has stated in interviews that this perception is not at all true. This vaccine
Jonas Salk got in. During his years at New York University Medical School, Salk worked as a laboratory technician during the school year and as a camp counselor in the summer. During Salk's medical studies, he stood out from his peers, according to Bookchin, "not just because of his continued academic prowess—he was Alpha Omega Alpha, the Phi Beta Kappa Society of medical education—but because he had decided he did not want to practice medicine." Instead, he became absorbed in research, even taking a year off to study biochemistry. He later focused more of his studies on bacteriology which had replaced medicine