Polio, also known as infantile paralysis, is transmitted by a virus. Although the disease appears throughout recorded history, it reached “epidemic proportions” throughout the developed world in the early 20th century.
In the United States, Vermont was the site of the first major polio epidemic in the summer of 1894.
In 1938, [President] Roosevelt founded the National Foundation for Infantile Paralysis and spearheaded the March of Dimes for polio research. In 1946, President Harry Truman declared polio a threat to the United States and called on Americans to do everything possible to combat it.
In the late 1940s, polio outbreaks in the U.S. increased in frequency and size, disabling an average of more than 35,000 people each year. Parents were frightened to let their children go outside, especially in the summer when the virus seemed to peak. Travel and commerce between affected cities were sometimes restricted. Public health officials imposed quarantines … on homes and towns where polio cases were diagnosed.
Not unlike an infection from SARS-CoV-2, some people infected with a polio virus had symptoms and some did not.
In about 98% of cases, polio is a mild illness, with no symptoms or with viral-like symptoms. In paralytic polio, the virus leaves the digestive tract, enters the bloodstream, and then attacks nerve cells. Fewer than 1%-2% of people who contract polio become paralyzed.
Dr. Jonas Salk was appointed to work with the National Foundation for Infantile Paralysis at the University of Pittsburgh in 1947. On 26 March 1953, he announced on a national radio show that he had successfully tested a vaccine for polio.
Famed CBS newsman Edward R. Murrow asked Salk who owned the patent to his vaccine. The scientist replied: “There is no patent. Could you patent the sun?”
Two days after the radio broadcast, the Journal of the American Medical Association published his research.
Salk administered the vaccine to volunteers who had not had polio, including himself, his lab scientist, his wife and their children. All developed anti-polio antibodies and experienced no negative reactions to the vaccine…
In 1954, national testing began on one million children, ages six to nine, who became known as the Polio Pioneers. On April 12, 1955, the results were announced: the vaccine was safe and effective. In the two years before the vaccine was widely available, the average number of polio cases in the U.S. was more than 45,000. By 1962, that number had dropped to 910.
Introduction of the vaccine did not proceed smoothly. More than 200,000 people received a defective vaccine manufactured at Cutter Laboratories in Berkeley, California. This batch had not inactivated the live virus. From those faulty vaccines, 40,000 contracted polio; 200 children had “varying degrees of paralysis” and 10 children died.
Reviewing failures in the manufacturing and inspection processes, [Paul Offit] exonerates Salk from blame and concludes that `the federal government, through its vaccine regulatory agency… was in the best position to avoid the Cutter tragedy’. Three larger companies produced safe polio vaccines according to Salk’s protocol for inactivating the virus with formaldehyde. The lack of experience and expertise at Cutter Laboratories, undetected by the inspectors, caused the disaster.
American physician and microbiologist Albert Sabin developed an oral polio vaccine.
He developed a live but attenuated oral vaccine that proved to be superior in administration, but also provided longer lasting immunity than the Salk vaccine. After a clash between the rival camps and their principals, by 1962 Salk’s vaccine was replaced by the Sabin vaccine.
Vaccines proved successful in eradicating polio in the United States and have eliminated it throughout most of the world.