title: Disease control and prevention in the 20th century: the role of immunization.
mesh_terms: D004679:Encephalomyelitis / Q000209:etiology; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D007114:Immunization / Q000009:adverse effects / Q000266:history; D010243:Paralysis / Q000209:etiology; D012900:Smallpox Vaccine / Q000009:adverse effects; D014611:Vaccination
chemical_list: D012900:Smallpox Vaccine