Jonas Salk’s polio vaccine was declared safe and effective April 12, 1955, leading to the eradication of the disease across much of the globe. 

April 12 marks 70 years since Jonas Salk’s polio vaccine was declared “safe, effective and potent,” and the  Salk Institute for Biological Studies is looking back on the history of what the organization’s president calls  “a remarkable breakthrough [that] changed the course of public health forever.”

The declaration verifying Salk’s vaccine meant “the beginning of the end for a disease that had terrorized families for generations,” Salk President Gerald Joyce said in a statement to lajolla.ca. “It was a victory not only for science but for humanity itself — a moment that reaffirmed what is possible when knowledge, collaboration and compassion come together.”

Jonas Salk, 1983
Salk Institute

Salk began his medical career just ahead of several polio epidemics that occurred between 1948 and 1955 in the US, epidemics that left those affected – mostly children – with face paralysis, lifelong disabilities or death.

At the Pittsburgh School of Medicine, Salk combined basic virology and knowledge of how vaccines work to create his vaccine, administering it to volunteers (including himself, his first wife and their children), all of whom developed anti-polio antibodies without adverse reactions.

Salk’s polio vaccine also underwent one of the largest medical trials in history, involving nearly two million children known as the “Polio Pioneers.”

After Salk’s vaccine was declared safe and effective, the average annual number of polio cases in the US decreased from 45,000 to 910 by 1962, and Salk’s approach to development informed prevention strategies for many other diseases.

Salk never patented the vaccine, which led to its rapid, widespread distribution; globally, polio cases have decreased by 99 percent since the vaccine’s introduction.