Jonas Salk

Contributor: Suzanne Riordan. Lesson ID: 13324

A devastating disease, a terrified public, a concerned president, and a fiercely determined lawyer — add an intense, innovative researcher for one of the greatest triumphs in medical history!


Life Science, United States

learning style
Auditory, Visual
personality style
Lion, Otter
Grade Level
High School (9-12)
Lesson Type
Dig Deeper

Lesson Plan - Get It!

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Although it had existed for years, a terrible disease grew worse in the 1950s and swept through the United States.

  • What was it, and how did it affect people?

Watch the video below for a brief history.

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Jonas Salk was an independent and unconventional scientist who took on the challenge of creating a vaccine for polio and accomplished his mission...and more.

Salk's Early Life

Born in New York City to a Russian Jewish immigrant family, Salk was an intelligent boy who wanted to do great things for the world. His parents encouraged him to get a good education and follow his dreams.

He considered studying law, but his mother convinced him to become a doctor. Salk graduated from the New York University School of Medicine and then went to work at Mount Sinai Hospital.

A few years later, he went to the University of Michigan and worked with a team studying flu viruses. It was there that he learned how to develop vaccines.

In 1947, Salk was hired by the University of Pittsburgh and began researching polio, then known as infantile paralysis. It was the most feared disease because it struck healthy people without warning, especially children, and could have devastating effects, as you saw in the opening video.

Polio Symptoms


Poliomyelitis, or polio, is an infectious disease that has varying effects on people. Up to 70% of people experience no symptoms at all. In some people, it produces a bad headache, sore throat, and muscle aches similar to the flu; they recover within a few weeks.

In a small number of cases, patients experience extreme muscle weakness, which affects their ability to move and breathe. Their muscles become very weak and hard to control, and it eventually leads to parallelization.

Those severely affected by polio are also in danger of dying because the muscles involved in breathing become too weak to do their job.

Even those who recover from polio can be affected by the disease later in life. Some of those infected as children can develop muscle weakness or even paralysis dozens of years later.

Polio Virus

polio RNS virus

The polio virus enters the body through the mouth via contact with infected food, water, or the droplets from sneezes and coughs of other people.

Once someone is infected, the virus can be passed to others for up to two weeks after symptoms appear.

Race for a Vaccine

At 39 (1921), Franklin D. Roosevelt became paralyzed from the waist down. At the time, his doctors believed it was from polio. (Today, experts believe he suffered from Guillain-Barre syndrome.)

Franklin D. Roosevelt, 1941

So when he became president (1933-1945), Roosevelt started a foundation called the March of Dimes to raise money for polio research and gave his legal adviser, Basil O'Connor, the job of drumming up pubic support and getting a vaccine created as soon as possible.

By 1952, the polio outbreak in the United States led to over 57,000 polio cases, with more than 21,000 of them involving paralysis.

Terrified at the prospect of their children suffering from this dreaded disease, the public pushed for a vaccine.

Many researchers were already working on a live virus vaccine. Still, Jonas Salk believed he could use a dead virus to develop a vaccine that would be quick to produce and highly effective.

Jonas Salk was considered an outsider in the scientific community. His work was often criticized by other scientists, especially Albert Sabin, who later developed his own polio vaccine.

Success and Failure

Eventually, Salk was ready to test his vaccine more widely. So beginning in April of 1954, in one of the largest medical trials in history, over 2 million children were injected with Salk's vaccine.

  • What happened?

A few months after the trial's findings were released, thousands of vaccinated children began contracting polio. Albert Sabin, who had warned against the rush to use Salk's vaccine, felt vindicated.

However, the problem was traced back to one lab that had not killed the virus properly and mistakenly injected children with a live virus.

This did not happen again once regulations were implemented to ensure the vaccines were done correctly. A week later, the vaccination program continued.

The vaccine proved safe and effective. Within a few years, polio cases were cut in half!

Watch the video below to review Jonas Salk's contribution.

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Polio Today

In 1962, Albert Sabin's oral vaccine was ready. It was easier to administer and cheaper to produce, so it became the main vaccine for many years in the U.S. and is still used in many countries.

Currently, in the U.S., children are given an injection of an inactivated polio vaccine in four doses: three as a baby and one from ages 4 to 6. Since 1979, there have been no cases of polio in the United States.

child vaccination

Now that you've learned the story of polio and Jonas Salk's fight to end it, head over to the Got It? page to learn more about Salk and decide if he deserved more recognition for his accomplishments!

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