The Salk Polio Vaccine Trial of 1954: risks, randomization and public involvement in research.

The year 2004 marks the fiftieth anniversary of the celebrated 1954 Salk Polio Vaccine Trial. This enormous clinical trial, involving 1.8 million children, was carried out with the co-operation and assistance of hundreds of thousands of lay volunteers, along with medical professionals and local health departments throughout the USA. While the trial was an impressive public health achievement, firmly establishing the efficacy of the killed virus vaccine and paving the way for eradication of the disease, it was not without controversy. This article recounts the story of this important early clinical trial and how the social and political conditions at the time affected its planning and execution.