TRANSFUSION TRANSMISSION OF RETROVIRUSES - HUMAN T-LYMPHOTROPIC VIRUSTYPE-I AND TYPE-II COMPARED WITH HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1

Background: The incidence of transfusion transmission of human T-lymph otropic virus type I (HTLV-I) and HTLV type II (HTLV-II) has not been compared directly or to that of human immunodeficiency virus type 1 (H IV-1). The effects of refridgerator storage of the blood component on infectivity of the viruses needs definition. Study Design and Methods: The circumstances influencing the transmission of HTLV-1, HTLV-II, an d HIV-1 via blood of donors whose sera were stored in a repository and who were retrospectively documented as having been infected at blood donation were examined. Confirmation and typing of anti-HTLV positivit y in donors and recipients used polymerase chain reaction, supplemente d by specific peptide testing. Results: Overall, 27 percent (26/95) of the recipients of blood components from anti-HTLV-I- and -II-positive donors became infected (9 with HTLV-I and 17 with HTLV-II). No recipi ents of acellular blood components became infected with HTLV-I or -II. There was no probable transmission by components stored >10 days. The rates of transmission for both viruses were similar: 0 to 5 days' sto rage, 17 (74%) of 23; 6 to 10 days, 8 (44%) of 18; and 11 to 14, 0 (0% ) of 10 (trend, p = 0.0002). In comparison, 89 percent (112/126) of th e recipients of anti-HIV-1-positive blood were infected regardless of component type, and no effect on transmission occurred with storage fo r <26 days. Conclusion: Transfusion-transmitted HTLV-I and -II are sim ilar. The data suggest that a donor's lymphocytes become noninfectious when they lose the ability to be activated or to proliferate.