[Evolution of the epidemic process of diphtheria in Leningrad over the past 25 years].
D004165:Diphtheria / Q000266:history* / Q000517:prevention & control; D004196:Disease Outbreaks / Q000517:prevention & control; D049673:History, 20th Century; D006801:Humans; D012426:Russia
Evoliutsiia épidemicheskogo protsessa pri difterii v Leningrade za poslednie 25 let