title: The prevalence of hepatitis B surface antigen in the Gampaha district.
abstract: OBJECTIVE
  To assess the prevalence and some epidemiological features of hepatitis B surface antigen (HBsAg) status in the Gampaha district.
  
  
  METHODS
  Community based survey.
  
  
  METHODS
  The district of Gampaha.
  
  
  METHODS
  All individuals over six months of age who were resident in the Gampaha district for a period over one month at time of survey.
  
  
  RESULTS
  The HBsAg positivity rate in the Gampaha district was estimated to be 2.5% (95% C.I. 2% to 3%). This places the area in the intermediate endemicity zone as classified by WHO. The epidemiology indicates horizontal intrafamilial spread being more important in the population studied, than vertical, parenteral or sexual routes of transmission.
  
  
  CONCLUSIONS
  The study suggests that immunisation in early childhood is an important measure in prevention of the infection in this district.
authors.affiliation: Epidemiology Unit, Ministry of Health, Colombo.
authors.forename: E
authors.initials: E
authors.lastname: Padmasiri
authors.forename: L
authors.initials: L
authors.lastname: Rajapaksa
authors.forename: W S
authors.initials: WS
authors.lastname: Jayakuru
authors.forename: N
authors.initials: N
authors.lastname: Withana
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology*; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D016036:Seroepidemiologic Studies; D013188:Sri Lanka / Q000453:epidemiology
chemical_list: D006514:Hepatitis B Surface Antigens