The Cutter Incident is a well known tragedy in which at least 200,000 children and adults were given a polio vaccine that was not properly inactivated.
The shots were given in 1955, just after they were first approved, and actually caused 40,000 cases of polio, including 10 deaths and 200 cases of paralysis.
The vaccines, made by Cutter Laboratories, were quickly recalled and vaccination eventually continued with polio vaccines made by other companies.
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