The changed epidemiology of hepatitis A infection in Scandinavia.

The prevalence of antibodies against hepatitis A virus (anti-HAV) was studied in a Swedish city population. A great difference was observed in different age groups. Anti-HAV was not found in the serum of young individuals while the prevalence was high in older ages (87% in individuals 60 years or older). This pattern of hepatitis A exposure is quite different from that reported for instance from the Mediterranean area and may indicate a very low frequency of hepatitis A exposure in Scandinavia today. The high prevalence of anti-HAV in older Swedes possibly reflects hepatitis A exposure in childhood during World War I and II when hepatitis A was more common.