title: Smallpox vaccination in the United States: the end of an era.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004641:Emigration and Immigration; D006801:Humans; D007109:Immunity; D007223:Infant; D008889:Military Personnel; D010564:Personnel, Hospital; D012899:Smallpox / Q000453:epidemiology / Q000401:mortality / Q000517:prevention & control*; D012900:Smallpox Vaccine / Q000009:adverse effects; D014195:Travel; D014481:United States; D014611:Vaccination / Q000009:adverse effects / Q000401:mortality / Q000706:statistics & numerical data*
chemical_list: D012900:Smallpox Vaccine