Community-based cross-sectional seroprevalence study of hepatitis A in Bangladesh

AIM: To elucidate the age-distribution of anti-hepatitis A virus (HAV) seroprevalence across different socioeconomic status (SES) categories in Bangladesh which, despite scarce data, is generally deemed to have high endemicity. METHODS: Blood samples of 818 subjects from a stratified sample of schools and hospitals, comprising different age categories and SES were collected. They were assayed for total anti-HAV antibodies. Social and medical history data were obtained using a questionnaire. RESULTS: Overall anti-HAV seroprevalence was 69.6%, increasing with age from 1-5 years (40.4%) to > 30 years (98.4%). Seroprevalence was lowest (49.8%) in the high SES group and highest (96.5%) in the rural lower-middle SES group. Among subjects aged 6-20 years, anti-HAV seroprevalence was lowest in urban private school children (43.0%), followed by urban government school children (76.2%) and rural school children (96.5%) (P < 0.01). Within the high SES group, anti-HAV seroprevalence was 32.3% in subjects < 10 years and 51.7% in those aged 11-20 years. Until now Bangladesh has been deemed to have high endemicity for HAV. CONCLUSION: The transition from high to intermediate HAV endemicity may be underway; high SES adolescents and adults remain particularly at risk of symptomatic illness. Preventive measures need consideration.