title: Hepatitis B viral infection in Shanghai and its prevention.
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002681:China; D003430:Cross-Sectional Studies; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged