Oral typhoid vaccine Ty21a.
D000284:Administration, Oral; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D006801:Humans; D012485:Salmonella typhi / Q000145:classification / Q000276:immunology*; D014435:Typhoid Fever / Q000517:prevention & control*; D014436:Typhoid-Paratyphoid Vaccines / Q000008:administration & dosage*
D014436:Typhoid-Paratyphoid Vaccines