Contribution of Haffkine to the concept and practice of controlled field trials of vaccines.
D022121:Cholera Vaccines / Q000266:history; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D007194:India; D010931:Plague Vaccine / Q000266:history; D012106:Research / Q000266:history; D014612:Vaccines / Q000266:history*
D022121:Cholera Vaccines; D010931:Plague Vaccine; D014612:Vaccines