As a member of the polio advisory committee of the United States Public Health Service, Paul joined in a 1962 recommendation that the use of an oral polio vaccine created by Albert B. Sabin in treating adults should be halted based on the lack of clinical evidence showing that the vaccine prevented those receiving the vaccine from developing the disease.[1] In his 1971 book A History of Poliomyelitis, Paul put forth the proposition that humans had always been exposed to poliovirus but had been protected by antibodies contained in the mothers milk, and that it was the clean water, sewer systems and improved hygiene of modern civilization that prevented children from being exposed to the virus at an early age, hypothesizing that protection would be conferred if people were exposed to the virus as infants.[5]