Chance favours the prepared mind.
D000818:Animals; D002645:Chickens; D002771:Cholera / Q000266:history* / Q000517:prevention & control; D022121:Cholera Vaccines / Q000266:history*; D049672:History, 19th Century; D014613:Vaccines, Attenuated / Q000266:history
D022121:Cholera Vaccines; D014613:Vaccines, Attenuated