AN INTERNATIONAL COLLABORATIVE STUDY OF THE EFFECTS OF COINFECTION WITH HUMAN T-LYMPHOTROPIC VIRUS TYPE-II ON HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 DISEASE PROGRESSION IN INJECTION-DRUG USERS

To determine whether human T-lymphotropic virus (HTLV) type II coinfec tion affects progression of human immunodeficiency virus type 1 (HIV) infection, longitudinal data on 370 HIV-infected injection drug users (IDUs) with known HIV seroconversion dates from four cohort studies we re pooled. HTLV infection was determined by EIA and confirmed and type d by Western blot. Proportional hazards models were used to determine whether HTLV-II infection was associated with AIDS or AIDS-related mor tality. Regression analyses were used to compare declines in CD4 cell percents in singly and dually infected persons. Of 370 IDUs, 61 (16%) were HTLV-II-coinfected. During follow-up, 43 (12%) developed and 24 ( 6%) died of AIDS. HTLV-II coinfection was not associated with progress ion to AIDS (relative hazard [RH], .82; 95% confidence interval [CI], 0.34-1.94]) or AIDS mortality (RH, 1.69; 95% CI, 0.62-4.60). Rates of decline in CD4 cell percent were similar in singly and dually infected IDUs. These results suggest that HTLV-II does not affect the progress ion of HIV infection.