Who was Jonas Salk?
Jonas Salk (October 28, 1914 - June 23, 1995) was born in New York City to Russian-Jewish immigrant parents. He attended medical school at New York University, but he chose to pursue medical research, instead of becoming a doctor. During medical school, he was offered a position to study the influenza virus, and he continued studying the flu virus after he graduated. He wanted to see if he could manipulate the virus so that it was no longer infectious but could still provide immunity.
In 1947, he moved to Pittsburgh, where he was offered a position researching the polio virus. For eight years, he worked diligently to developed a "killed" virus that would provide immunity without infecting the person receiving the vaccine. Much of the work he had done on the influenza virus carried over to his work with the polio virus.
In 1948, J.F. Enders' team at Harvard announced that they could grow viruses in tissue samples, which allowed Salk to more easily complete his studies. In 1952, Salk successfully created a killed virus vaccine for the polio virus. The news wasn't released to the world until April 12,1955. They started passing out the vaccine, given by injection, that same year.