Jonas Salk's 1955 vaccine targeted which disease?

Jonas Salk’s vaccine, introduced in 1955, targeted polio.

Salk and his team at the University of Pittsburgh developed an inactivated poliovirus vaccine, commonly called IPV. It used virus particles killed with formaldehyde, designed to train the immune system without causing the disease. The vaccine was tested in a huge 1954 field trial involving roughly 1.8 million children, one of the largest medical experiments of its time.

On 12 April 1955, the vaccine was declared safe and effective, and mass vaccination began in the United States. Polio had been a major public-health threat because infection could damage the nervous system and cause permanent paralysis, especially in children.

A frequent mix-up is Salk’s vaccine versus Albert Sabin’s later oral polio vaccine. Salk’s was injected and inactivated; Sabin’s, introduced in the early 1960s, used weakened live virus and was taken by mouth. Both helped drive the worldwide decline of polio.