To determine the level of immunity to hepatitis A virus infection in rural Australian Aboriginal populations in the "Top End" of the Northern Territory. A total of 344 sera, for which details of donors' age, sex and domicile were available, were collected and tested for hepatitis A total antibody in a delinked seroprevalence study. Overall, 337/344 samples (97.97%) tested positive for hepatitis A total antibodies--18/20 samples (90%) in the 1-5 year age group; 85/88 (96.6%) in the 6-10 year age group; 98/98 (100%) in the 11-15 year age group; 32/33 (97.0%) in the 16-20 year age group and 104/105 (99%) in the older than 20 year age group.
Hepatitis A is hyperendemic in the rural Aboriginal communities studied and the virus is acquired predominantly in the first five years of life. Symptomatic hepatitis A infection is uncommon in this population. We suggest that hepatitis A vaccination for rural Aboriginal children is not indicated as it would not reduce clinical disease rates and may produce a cohort whose immunity could decrease over the following 10 years. Although vaccination is appropriate for non-immune individuals working in remote communities, emphasis must be placed on the inequities in health infrastructure and education underlying the high transmission rates in Aboriginal children.
Should aboriginals in the "top end" of the Northern Territory be vaccinated against hepatitis A?