[The epidemic process and its essence].
D004196:Disease Outbreaks; D004197:Disease Reservoirs; D004463:Ecology; D006801:Humans; D010272:Parasitic Diseases / Q000469:parasitology; D010686:Philosophy, Medical; D012959:Socioeconomic Factors
Epidemicheskiĭ protsess i ego sushchnost'.