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Jonas Salk (1914-1995) 1939 Salk graduates with an MD from New York University1942 Joins the University of Michigan influenza immunization project1947 Begins research into poliomyletis at the University of Pittsburgh1953 Salk announced a new vaccine to immunize people against polio(Polio is an acute viral infectious disease that can destroy motor neurons and lead to paralysis)1955 Salk's vaccine is declared safe and effective in the United States