Jonas Salk and Polio Polio is a viral disease that produces flu-like symptoms and may occasionally cause
muscle weakness or paralysis. Throughout the first half of the twentieth century, the
disease was common, and parents feared that their children would lose the ability to
move their arms or legs. In 1947, Dr. Jonas Salk began studying polio at the University of
Pittsburgh in search of an answer. He discovered three basic types of polio viruses and
began to develop a vaccine that would protect against all three. Testing began in 1952,
with vaccinations eventually given to about two million children. The vaccine was shown
to be effective and was put into general use in 1955. Jonas Salk became a hero and
received an award from President Dwight D. Eisenhower.
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