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
Lee Salk his older brother. Salk attended the University of Michigan. Salk's published work investigated the effect of retirement on mortality, the effect of the mother's heartbeat on the newborn, and the relationship between adverse maternal and perinatal conditions and later self-destructive behavior. He was the author of eight books. Salk was married twice, first to Kerstin and then Mary Jane. He had two children from his first marriage, a son Eric and daughter Pia. Salk developed cancer and died in hospital in Manhattan at age 65 on May 2, 1992. Salk was a professor at Cornell University Medical Center. Lee Salk