Thomas Francis 
Polio

''Thomas Francis Jr. (July 15, 1900 October 1, 1969) was an American physician, virologist, and epidemiologist. Francis was the first person to isolate influenza virus in America, and in 1940 showed that there are other strains of influenza, and took part in the development of influenza vaccines.  He joined an elite research team at the Rockefeller Institute, first doing research on vaccines against bacterial pneumonia, later he took up influenza research.''  Wiki

"Dr. Thomas Francis did not mention in his key evaluation of the 1954 Salk field trials that those who contracted polio after their first innoculation and before their second inoculation were placed in the "not-inoculated" list.' (Maurice B. Bayly, The Story Of The Salk Anti-poliomyelitis Vaccine, 1956).