In 1955, when the polio vaccine became widely available in the United States, it was the news the nation had been waiting for. The disease had taken the lives of thousands, and left thousands more with permanent paralysis. Children were particularly affected, but beyond that, polio did not discriminate. It affected all races and income levels equally. “There were summertime epidemics every year,” said Dr. William Petri, chief of the Division of Infectious Diseases and International Health at the University of Virginia. “In 1916, there were 2,000 deaths in New York City alone.”