Salk was not the first to develop a vaccine against polio for in 1935 killed and attenuated vaccines were...
2 Answers · Education & Reference · 12/06/2007
..." "Inject and Ingest: Two Forms of Polio Vaccination" Etc. Good luck!
2 Answers · Education & Reference · 13/09/2009
i would try finding a newspaper article or something from the time period. you can check in a library or on possibly on the web. a diary with that info in it, a scientific journal from the time are also ways. this might be hard to find though. good luck
2 Answers · Education & Reference · 02/01/2010
Look up Jonas Salk, who is associated with the first Polio Vaccine .
2 Answers · Education & Reference · 12/04/2008