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Clinical Trials

Chief objective: To determine whether a … poliomyelitis vaccine would afford protection against naturally occurring paralytic poliomyelitis in selected groups of children … and if protection is provided, the degree of such protection.
Evaluation of the 1954 Field Trial of Poliomyelitis Vaccine: Final Report, 1957

The National Foundation for Infantile Paralysis chose Dr. Thomas Francis Jr. at the University of Michigan to implement the first mass polio vaccine trial in 1954. More than 300,000 people, mostly volunteers, including physicians, nurses, schoolteachers, public health officials, and community members, carried out the work.


Polio Pioneer card given to each child, along with a piece of candy, 1954

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Polio Pioneer pin given to each child, 1954

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Polio Pioneers

In 1954, almost 75 percent of reported poliomyelitis cases occurred in people under twenty years of age, and 50 percent in children under ten. The trial’s study population, then, targeted some 1.8 million children in the first three grades of elementary school at 215 test sites. In the double-blind experiment, 650,000 children received vaccine, 750,000 received a placebo (a solution made to look like vaccine, but containing no virus), and 430,000 served as controls and had neither. All were “Polio Pioneers.”

Randall Kerr gets the first shot, Franklin Sherman Elementary School, Fairfax, Virginia, April 26, 1954
Courtesy of March of Dimes

Randall Kerr’s vaccination record card from the 1954 clinical trial

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IBM punch card used to tabulate data from the 1954 clinical trial

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The study called for all children receiving vaccine or placebo to have three intramuscular injections over a five-week period. About 2 percent of the children also gave blood samples to verify their immune response.

Data from all 1,829,916 clinical trial participants were entered on IBM punch cards and tabulated. The study evaluated every scrap of evidence, from the registration methods of the participants to laboratory procedures to statistical analysis.

The news that began to pour out over the radio in the gym on April 12, 1955, the tenth anniversary of Roosevelt’s death, was news only in detail. That the field trials of the Salk vaccine would prove in some measure successful had been anticipated. Indeed, the assistant to the director at the previous hospital had remarked to me in November, ‘Too bad you didn’t wait a year. The vaccine sure looks good.’
Edward LeComte, 1957

Contact sheet of photographs from the April 12, 1955, announcement day
Courtesy of SBC Knowledge Ventures and University of Michigan, Bentley Historical Library, Michigan Bell Telephone Company Photographs, Folder 584, Box 18, Michigan Bell Photographers

University of Michigan press release issued for Dr. Thomas Francis’s announcement that the vaccine worked
Courtesy of University of Michigan, Bentley Historical Library, University of Michigan News and Information Services, Box 9

There is great assurance that the study, both in design and performance, is a contribution of major value to the field of medical research, generally. It is gratifying that the undertaking provided knowledge which unequivocally established the product developed by Dr. Salk as an effective vaccine for the prevention of poliomyelitis.
Dr. Thomas Francis, 1955