title: Immunization levels in Boston schools--a second look.
mesh_terms: D001900:Boston; D002648:Child; D002675:Child, Preschool; D004165:Diphtheria / Q000517:prevention & control; D006306:Health Surveys; D006801:Humans; D007114:Immunization / Q000706:statistics & numerical data*; D007883:Legislation, Medical; D008404:Massachusetts; D008913:Minority Groups; D011051:Poliomyelitis / Q000517:prevention & control; D012572:School Health Services; D013742:Tetanus / Q000517:prevention & control; D014917:Whooping Cough / Q000517:prevention & control