Acute hepatitis B in western Sweden - Genotypes and transmission routes

A retrospective study of acute hepatitis B (AHB) during 1995-1996 in Gotebo rg, Sweden, was carried out to investigate whether the increasing number of hepatitis B virus (HBV) carriers due to immigration in northwestern Europe has influenced the incidence or genotype heterogenicity. 24 cases of AHB w ere identified, the probable transmission route of which was intravenous dr ug use (IVDU) in 11 (46%), heterosexual in six (25%), homosexual in one, he modialysis in two and unknown in four cases. In no case was the source an i mmigrant with chronic HBV infection. Genotype D was seen in 12 patients, se ven being anti-HCV-positive IVD users, two probably infected heterosexually and three with an unknown source. Genotype A was found in six patients: th ree IVD users,a sexual partner of an IVD user and two dialysis patients. Ge notype B was found in one patient infected during travel to Vietnam, and ge notype C in one patient, probably infected sexually from a previously ident ified chronic carrier. In conclusion, genotype D is the main genotype and I VDU still the major risk factor for AHB in Goteborg, while transmission fro m immigrants appears to be of minor importance despite the fact that this g roup comprises over 90% of the young, highly infectious carriers.