title: Prevalence of chronic hepatitis B in South Western Sydney: evaluation of the country of birth method using maternal seroprevalence data.
abstract: OBJECTIVE
  To estimate the prevalence of hepatitis B infection and evaluate the country of birth (Census) method of describing hepatitis B distribution in an Australian health service with a large migrant population.
  
  
  METHODS
  The prevalence of chronic hepatitis B in Sydney South West Area Health Service (SSWAHS, population 1.3 million) was estimated by applying the prevalence of hepatitis B surface antigen (HBsAg) in high or intermediate hepatitis B prevalence countries to SSWAHS residents from those countries, using 2006 Census data. The Australian hepatitis B prevalence (0.7%) was applied to the remainder. This method was validated using HBsAg seroprevalence in 42,274 women aged 15-44 years who delivered at SSWAHS public maternity hospitals during 2007 to 2009.
  
  
  RESULTS
  The SSWAHS prevalence of HBsAg using the Census method was 2.0% for all ages and 2.3% for 15-44 year old women. The seroprevalence in 15-44 year old mothers was 1.8%. The adjusted population prevalence was 1.6%. The two methods produced broadly similar descriptions of relative hepatitis B burden by local government area and country of birth.
  
  
  CONCLUSIONS
  The Census method overestimates the prevalence of hepatitis B infection by 30%, but produces similar patterns of hepatitis B burden across the area. Health services can estimate the prevalence and distribution of chronic hepatitis B using readily available data to focus delivery of prevention and treatment services.
authors.affiliation: Public Health Unit, Sydney South West Area Health Service, New South Wales. caroline.turnour@doh.health.nsw.gov.au
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Turnour
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Cretikos
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Conaty
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001315:Australia / Q000453:epidemiology; D019352:Censuses; D002648:Child; D002675:Child, Preschool; D054242:Emigrants and Immigrants / Q000706:statistics & numerical data*; D005260:Female; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D019694:Hepatitis B, Chronic / Q000453:epidemiology* / Q000208:ethnology / Q000276:immunology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D036801:Parturition; D044382:Population Groups; D015995:Prevalence; D012042:Registries; D015203:Reproducibility of Results; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012737:Sex Factors; D055815:Young Adult
chemical_list: D006514:Hepatitis B Surface Antigens