“…any possible doubts, whether or not well founded, about the safety of the [oral polio] vaccine cannot be allowed to exist in view of the need to assure that the vaccine will continue to be used to the maximum extent consistent with the nation’s public health objectives.”
Department of Health and Human Services, Food and Drug Administration,
21 CFR Part 630 Additional Standards for Viral Vaccines; Poliovirus Vaccine, Live, Oral; Final Rule
Federal Register Vol. 49, No. 107, June 1, 1984