Polio vaccine poliomyelitis per million doses given. This compares with 5,000 cases per million who are paralysed following a polio infection. Both are generally safe to give during pregnancy and in those who have HIV/AIDS but are otherwise well. The first polio vaccine was the inactivated polio vaccine. It was developed by Jonas Salk and came into use in 1955. The oral polio vaccine was developed by Albert Sabin and came into commercial use in 1961. They are on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. The wholesale cost in
Jonas Salk the University of Michigan. Francis had recently joined the faculty of the medical school after working for the Rockefeller Foundation, where he had discovered the type B influenza virus. According to Bookchin, "the two-month stint in Francis's lab was Salk's first introduction to the world of virology—and he was hooked." After graduating from medical school, Salk began his residency at New York's prestigious Mount Sinai Hospital, where he again worked in Francis's laboratory. In 1947, Salk became ambitious for his own lab and was granted one at the University of Pittsburgh School of Medicine, but the lab was smaller than