Hepatitis A in Swedish foreign travellers.

Scandinavians present antibodies to hepatitis A virus (anti-HAV) in low frequency or under 25% in ages up to 50 years. This means that Scandinavians ought to be particularly vulnerable when travelling to hyperendemic hepatitis A areas. About one million Swedes travel to the Mediterranean area each year and about 75% of these travellers receive gammaglobulin before departure. Since hepatitis A is a notifiable disease in Sweden it is possible to compare the incidence of this disease in travellers during different periods of time. In the early seventies the prevalence of hepatitis A in Mediterranean travellers was one case in about 3000 travellers, while in 1980 the calculated prevalence had declined to one case in about 6000 travellers without gammaglobulin prophylaxis. The declining prevalence of hepatitis A in Swedish travellers to the northern part of the Mediterranean area is probably due to increased socio-economic and hygienic standard in the countries concerned. The relatively low prevalence of hepatitis A infection among Swedish travellers to the northern part of the Mediterranean area is in sharp contrast to the high prevalence found in Northern Africa and the Middle East (one case in about 300 travellers) as well as in Tropical Africa and Asia (one case in about 100 travellers).