A paralyzed man in a negative pressure ventilator, 1950s, commonly known as an “iron lung.” This device enabled a patient with loss of muscle control to breathe. People infected with poliomyelitis, an acute viral infection, sometimes experienced paralysis and had to be placed in an iron lung. In 1955, Eli Lilly and Company and other pharmaceutical manufacturers mass-produced the Salk polio vaccine to help prevent future cases of polio-based paralysis.