EPIDEMIOLOGIC COMPARISON OF HUMAN T-LYMPHOTROPIC VIRUS TYPE-I-INFECTED BLOOD-DONORS FROM ENDEMIC AND NONENDEMIC REGIONS OVER A 3-YEAR PERIOD

Background: Screening for human T-lymphotropic virus type I (HTLV-I) i nfection became systematic in 1989 in the French West Indies for blood from all donors and in France for blood from natives of endemic areas ; in 1990, it was extended to blood from donors with at-risk sex partn ers and in July 1991 to blood from all donors. Study Design and Method s: The epidemiologic characteristics of individuals found through the screening of donated blood to be HTLV-I infected were compared for an endemic region (Guadeloupe, French West Indies) and a nonendemic regio n (Paris area) over a 3-year period (1989 through 1991). Results: In G uadeloupe, 131 HTLV-I-infected individuals were detected in the screen ing of 28,801 units; in the Paris area, 38 HTLV-I-infected donors were detected in the screening of 109,824 units. All Guadeloupean HTLV-I-i nfected donors were natives of endemic areas. Among the 38 Parisian HT LV-I-infected donors, 21 were natives of endemic areas, 10 were native s of endemic areas and had received transfusions, 2 were whites who ha d received transfusions, and 5 were whites who had had heterosexual co ntact with natives of endemic areas. The percentage of HTLV-I-infected individuals whose blood would have been excluded because of positivit y for one or more markers for other viruses did not significantly chan ge over the study period and did not significantly differ between regi ons (41%). Among the eight Parisian HTLV-I-infected blood donors detec ted after July 1991, six would not have been detected without the biol ogic screening. Conclusion: The generalization of biologic screening o f HTLV-I-infected donated blood in France was useful for the preventio n of HTLV-I and HTLV type II infections through transfusion.