Polio vaccine 900 developed polio; in the group receiving the vaccine, only one out of 7,500 developed polio, making the vaccine 88% effective during the first year. However, other researchers believed that the one case was likely caused by the vaccine, and two more possible cases were reported later. After this meeting, Brodie, whose polio vaccine was at least partially effective and reasonably safe, and who developed several ground-breaking ideas about vaccination whose validity was confirmed two decades later with the development of the Salk vaccine, was immediately fired and had trouble finding employment again. Brodie died three and a half years
Jonas Salk "I had an opportunity to spend time in elective periods in my last year in medical school, in a laboratory that was involved in studies on influenza. The influenza virus had just been discovered about a few years before that. And, I saw the opportunity at that time to test the question as to whether we could destroy the virus infectivity and still immunize. And so, by carefully designed experiments, we found it was possible to do so." In 1941, during his postgraduate work in virology, Salk chose a two-month elective to work in the laboratory of Thomas Francis at