title: Smallpox studies in Madras City, India.
mesh_terms: D004196:Disease Outbreaks / Q000453:epidemiology*; D006801:Humans; D007194:India; D012899:Smallpox / Q000453:epidemiology* / Q000401:mortality / Q000517:prevention & control; D014611:Vaccination; D012901:Variola virus / Q000302:isolation & purification; D014944:World Health Organization