Polio Epidemic Timeline

Following the 1916 epidemics and having experienced little success in treating polio patients, researchers set out to find new and better treatments. Between 1917 and the early 1950s, several therapies were explored in an effort to prevent deformities, including hydrotherapy and electrotherapy.

Some families received support through philanthropic organizations such as the Ancient Arabic Order of the Nobles of the Mystic Shrine fraternity, which established a network of pediatric hospitals in 1919, the Shriners Hospitals for Children, to provide care free of charge for children with polio.

Image source: Shriners Hospitals for Children

In 1926, Franklin Roosevelt, convinced of the benefits of hydrotherapy, bought a resort at Warm Springs, Georgia, where he founded the first modern rehabilitation center for treatment of polio patients, which still operates as the Roosevelt Warm Springs Institute for Rehabilitation.

Image source: Warm Springs Historic District

In treating polio cases in rural Australia between 1928 and 1940, Sister Elizabeth Kenny developed a form of physical therapy that—instead of immobilizing affected limbs—aimed to relieve pain and spasms through hot, moist packs and early activity and exercise to maximize the strength of unaffected muscle fibers.

The first iron lung used in the treatment of polio was invented by Philip Drinker, Louis Agassiz Shaw, and James Wilson at Harvard, and tested October 12, 1928, at Children's Hospital, Boston.

Image source: Iron lung

In 1940, Sister Elizabeth Kenny, an Australian bush nurse from Queensland, arrived in North America and challenged the standard immobilization approach to polio treatment. Slowly her ideas won acceptance, and by the mid-20th century had become the hallmark for the treatment of paralytic polio.

When the big polio epidemic hit Denmark in 1952, the epidemic hospital, Blegdamshospitalet in Copenhagen, had only one Emerson iron lung and some cuirass-type ventilators. Large numbers of patients were ventilated by hand ('bagged') by medical students and anyone else on hand because of the large number of bulbar polio patients.

Image source: Bjørn Aage Ibsen

The hand-ventilation crisis during the Copenhagen epidemic led to the invention of the positive pressure ventilator by anesthesiologist Bjørn Aage Ibsen in 1952. Lessons from Copenhagen bore fruit in Stockholm one year later in 1953 during the next European polio epidemic.

The Emerson Iron Lung, a widely used negative-pressure ventilator for polio patients, was produced until 1970.

In 2009 as part of the Q150 celebrations, the Kenny regimen for polio treatment was announced as one of the Q150 Icons of Queensland for its role as an iconic 'innovation and invention'.

Image source: Elizabeth Kenny

By 2025, the majority of those polio survivors who need artificial respiration use the positive pressure ventilator, reflecting the lasting impact of Ibsen's innovation during the 1952 Copenhagen epidemic.

In 1935 Maurice Brodie, a research assistant at New York University, and William Hallock Park of the New York City Department of Health attempted to produce a polio vaccine, procured from virus in ground up monkey spinal cords and killed by formaldehyde.

Image source: Polio vaccine

In 1938 Roosevelt helped to found the National Foundation for Infantile Paralysis (now known as the March of Dimes), that raised money for the rehabilitation of people with paralytic polio, and was instrumental in funding the development of polio vaccines.

Image source: March of Dimes

In 1950 William Hammon at the University of Pittsburgh isolated serum, containing antibodies against poliovirus, from the blood of polio survivors. Between September 1951 and July 1952 nearly 55,000 children were involved in a clinical trial of the anti-polio serum.

The first successful demonstration of a polio vaccine was by Hilary Koprowski in 1950, using a live attenuated virus in an oral vaccine.

Image source: Hilary Koprowski

The first polio vaccine was developed by Jonas Salk, first tested in 1952 using the HeLa cell, and announced to the world by Salk on April 12, 1955.

Image source: Jonas Salk

Researchers including Enders, Weller, and Robbins were recognized for their labors with the Nobel Prize in 1954 for their work enabling the growth of poliovirus in tissue culture, paving the way for vaccine development.

In 1954, the Salk vaccine was tested for its ability to prevent polio; its field trials grew to be the largest medical experiment in history. By 1955 the March of Dimes had invested $25.5 million in research, funding both Jonas Salk's and Albert Sabin's vaccine development, the field trial, and supplies of free vaccine for thousands of children.

On April 12, 1955, Jonas Salk announced his polio vaccine to the world, and in 1955 it was chosen for use throughout the United States.

By 1957, following mass immunizations promoted by the March of Dimes, the annual number of polio cases in the United States was reduced, from a peak of nearly 58,000 cases, to 5,600 cases.

Human trials of Albert Sabin's oral polio vaccine began in 1957 and it was licensed in 1962.

Image source: Albert Sabin

Following the development of oral polio vaccine, a second wave of mass immunizations led to a further decline in the number of cases: by 1961, only 161 cases were recorded in the United States.

Polio survivors were often in the forefront of the disability rights movement that emerged in the United States during the 1970s, and pushed legislation such as the Rehabilitation Act of 1973 which protected qualified individuals from discrimination based on their disability, and the Americans with Disabilities Act of 1990.

Image source: Americans with Disabilities Act of 1990

In 1977, the National Health Interview Survey reported that there were 254,000 people living in the United States who had been paralyzed by polio.

Image source: Post-polio syndrome

The World Health Organization estimated that there were 10 to 20 million polio survivors worldwide in 2001. According to local polio support groups and doctors, some 40,000 polio survivors with varying degrees of paralysis lived in Germany, 30,000 in Japan, 24,000 in France, 16,000 in Australia, 12,000 in Canada and 12,000 in the United Kingdom.