PREVALENCE OF HUMAN T-CELL LYMPHOTROPIC VIRUS TYPE-1 (HTLV-1) AND HTLV-2 INFECTION AMONG SPANISH DRUG-USERS MEASURED BY HTLV-1 ASSAY AND HTLV-1 AND HTLV-2 ASSAY

The prevalence of human T-cell lymphotropic virus type 1 (HTLV-1) and HTLV-2 infection in 1992 and 1993 was determined by testing 2,152 spec imens from injection drug users living in 11 geographic areas of Spain . Results obtained by an authentic HTLV-1 and -2 test were compared wi th those obtained by an HTLV-1 assay. HTLV infection was identified in 7 of 11 regions, with an overall prevalence of 2.5% (range, 0.4 to 11 .5%). Fourty-four (81%) of 54 subjects were infected with HTLV-2; the viral strains in the remaining 10 subjects could not be serologically typed. Underestimation of HTLV infection because of the low sensitivit ies of HTLV-1 enzyme immunoassays for HTLV-2 antibody was relatively l ow (<20%). Therefore, previous epidemiologic findings generated with H TLV-1 enzyme immunoassays appear to be reasonably accurate. Our result s suggest that the rate of HTLV infection may have been increasing rec ently among Spanish drug users.