HTLV-I AND HTLV-II IN INTRAVENOUS-DRUG-USERS FROM SWEDEN AND DENMARK

693 IVDU (intravenous drug user) sera from Copenhagen, Malmo and Stock holm were tested, 247 retro- and 446 prospectively, for antibodies to human T-lymphotropic virus (HTLV), types I and II, by means of a comme rcial whole-virus EIA and/or an HTLV-I/-II peptide-based EIA. Positive EIA reactions were checked and typed by electrophoretic immunoblottin g, a differential peptide-based EIA and nucleic acid amplification/hyb ridization with HTLV-I and -II specific primers and probes. 3 (0.7%) o f the prospectively tested IVDUs from Malmo, none of 100 from Stockhol m and none of 45 from Copenhagen were HTLV-seropositive. The 3 Malmo I VDU cases were a female immigrant from South America, her male native Swedish spouse (both HTLV-I), and a male immigrant Italian heroinist ( HTLV-II). We conclude that HTLV was uncommon among intravenous drug us ers, a sentinel population, in Sweden and Denmark during 1986 and 1989 . However, the occurrence of 3 HTLV-positive cases in Malmo 1993 indic ates that the situation can change rapidly.