The Center for the History of Medicine

Polio Exhibit

The 1995 Announcement of the Vaccine Field Trial Results

Thomas Francis Jr.

"Safe, effective, and potent." With these words forty years ago, Dr. Thomas Francis Jr., director of the Poliomyelitis Vaccine Evaluation Center headquartered at the University of Michigan, announced to the world that the Salk polio vaccine was 60-90% effective in preventing paralytic polio. The long campaign against this most virulent of childhood diseases, though certainly not over, was about to enter its final stages.

Within a generation, the scourge that was polio would be but a memory to most Americans. Although Francis had guarded against any premature leakage to the press of the results of the test, informed bystanders noted that the day for the announcement -- April 12, 1955 -- was the tenth anniversary of the death of Franklin D. Roosevelt. It was unlikely that the National Foundation for Infantile Paralysis, the primary funding agency for the polio field trial, was going to use the occasion to release bad news.

Among the news media and the scientific community, there was intense anticipation of what Francis would have to report. University administrators, aware of the drama of the situation, selected the Rackham Building assembly hall as the most appropriate forum for Francis to make his announcement.

Thomas Francis Jr. (L) and Jonas Salk (R)

Before an audience of press and distinguished scientists, Francis was joined on stage by Jonas Salk, the vaccine's developer, and Basil O'Connor, president of the National Foundation for Infantile Paralysis. Other polio experts also spoke, but without question, the day belonged to Salk and Francis. Dr. Francis jealously guarded the findings of the test up until the last moment. Premature disclosure, especially if misreported, could adversely affect the continuing struggle to find a cure for polio. Even Dr. Salk did not know the details of the test results, although he certainly must have had some idea that his vaccine was effective.

View of the stage, Rackham Auditorium

Swarms of press and TV and radio reporters crowded outside the Rackham auditorium hoping to snatch a copy of the published report as it arrived. Here is one press report:

Finally the reports arrived -- under armed guards, one a captain of the Ann Arbor Police Department. The releases were in boxes on a hand truck. To avoid a crush, public relations men from the University began throwing the releases to the crowd. But still hands grabbed at the boxes. In the next few seconds toes were trampled on, ribs were elbowed and pandemonium prevailed. Then there was a dash for the couple of dozen typewriters in the press room and for a battery of telephones.

References:

Salk Introductory Remark
Salk's Report
Press Release

Photo Credits:

Thomas Francis at microphone: Michigan Bell Telephone Company Photographs, Box 18.

Tomas Francis and Jonas Salk at Announcement: University of Michigan School of Public Health Photographs, Box 6.

Polio Vaccine Announcement Stage: University of Michigan Redia Resources Center Records, Box 33, Bentley Historical Library, University of Michigan.

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