title: A seroepidemiological study of the prevalence of hepatitis B infections in a hyperendemic New Zealand community.
abstract: The prevalence of hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs) were studied in 93% of the population of the New Zealand township of Kawerau. Sera were collected from 7901 subjects over six months old, and 3318 (42%) had markers of hepatitis B virus (HBV) infections. Five hundred and nineteen (6.6%) were positive for HBsAg and 485 (96.4%) of 503 retested were confirmed as chronic carriers. HBsAg prevalence was 5.4% in the 0-4 years age group but only 1 of 66 children under one year old was positive suggesting that later cross infection, rather than perinatal transmission was the major factor responsible for the high pre-school carrier rate. Total HBV marker prevalence increased dramatically in early school years and peak marker prevalence was 67.7% in the 15-19 year age group. Prevalence of HBsAg was more than four times higher in non-europeans than in Europeans (Caucasians). Other factors significantly associated with hepatitis B virus marker prevalence in children were: number of years spent in Kawerau, which was associated with anti-HBs prevalence; and size of household, which was associated with HBsAg prevalence. Number of siblings was not a significant risk factor over and above the effect of size of household. Factors associated with marker prevalence in adults were: number of years spent in Kawerau, which was associated with anti-HBs; birth in the Northern half of the North Island, which was associated with both HBsAg and anti-HBs; size of household, which was more strongly associated with HBsAg prevalence; and amateur tattoos, which were associated with anti-HBs prevalence but not with HBsAg prevalence.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002353:Carrier State / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005060:Europe / Q000208:ethnology; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology*; D006510:Hepatitis B Antibodies / Q000032:analysis; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009520:New Zealand; D012737:Sex Factors
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens