Hepatitis virus infection in an isolated Canadian Inuit (Eskimo) population.

The epidemiology of Hepatitis A virus (HAV) and hepatitis B virus (HBV) infection was studied in a northern Canadian Inuit (Eskimo) settlement. Sera from 720 of the 850 inhabitants of Baker Lake, Canada, were tested for markers of HAV and HBV infection. Anti-HAV was present in 71% of the residents and its prevalence increased with age. Serologic evidence of HBV infections was found in 27% of residents. The prevalence increased with age, being uncommon under the age of 20 (6%) and almost universal over the age of 60 (93%). Among the 29 hepatitis B surface antigen (HBsAg) carriers identified, all were adults, all had low levels of HBsAg, and all were negative for hepatitis B e antigen (HBeAg) and DNA polymerase but positive for antibody to HBeAg. These data demonstrate a high prevalence of HAV and HBV infection in this population. Further, they suggest that a dramatic decrease in the transmission of HBV infection has occurred over the past 20-30 years.