Dr.Jonas Salk administered one of the first polio shots.

On February 23, 1954, a group of children from Arsenal
Elementary School in Pittsburgh, Pennsylvania, receive the
first injections of the new polio vaccine developed by Dr.
Jonas Salk (above). Thanks to the vaccine, by the 21st
century polio cases were reduced by 99 percent worldwide.

Though not as devastating as the plague or influenza,
poliomyelitis was a highly contagious disease that emerged
in terrifying outbreaks and seemed impossible to stop.

Attacking the nerve cells and sometimes the central nervous
system, polio caused muscle deterioration, paralysis and even
death. Even as medicine vastly improved in the first half of the
20th century in the Western world, polio still struck, affecting
mostly children but sometimes adults as well.

The most famous victim of a 1921 outbreak in America was
future President Franklin Delano Roosevelt, then a young
politician. The disease spread quickly, leaving his legs
permanently paralyzed.

On April 26, 1954, the Salk polio vaccine field trials, involving 1.8
million children, began at the Franklin Sherman Elementary School
in McLean, Virginia. Children in the United States, Canada and
Finland participated in the trials, which used for the first time the
now-standard double-blind method, whereby neither the patient
nor attending doctor knew if the inoculation was the vaccine or a placebo.

One year later, on April 12, 1955, researchers announced the vaccine
was safe and effective and it quickly became a standard part of childhood immunizations in America.

MIKE GRACIA

On this day in 1972, President Richard M. Nixon and White House
chief of staff H.R. Haldeman discussed a plan to use the CIA to
obstruct the FBI’s Watergate investigation. A tape recording of this meeting between the two men in the Oval Office became known as
the “Smoking Gun” tape.

President Richard Nixon (seated) meeting with Chief of Staff H. R. (“Bob”) Haldeman in the White House.

On this day in 1940, Adolf Hitler (center) visits Paris after France falls
to Nazi Germany.

It was on this day in 1995 when Dr. Jonas Salk died from heart
failure.

TIME Magazine Cover: Dr. Jonas Salk — Mar. 29, 1954.

Jonas Edward Salk (October 28, 1914 – June 23, 1995)