Epidemiological characteristics of HTLV-I and II co-infection in Brazilian subjects infected by HIV-1

ABSTRACT

Serum samples from 895 HIV-1 infected individuals were tested for antibodies against HTLV-I and HTLV-II. The overall prevalence of the co-infection was high (16.3 percent). Epidemiological information was obtained from each subject including gender, age, intravenous drug use (IVDU), blood transfusion, previous diagnosis of sexually transmitted diseases (STD) and sexual behavior. The risks for acquiring retroviral infections other than HIV-1 were evaluated and the prevalence of co-infection was compared according to the AIDS clinical status. We detected seven cases (0.9 percent) of triple infection. HTLV-I co-infection was associated with blood transfusion (p=0.009). Women co-infected by HTLV-I or HTLV-II had a higher risk of AIDS than those infected only by HIV-1 (RR=2.04; 95 percent CI 1.27-3.27, p=0.007 and RR=3.09; 95 percent CI 1.07-8.91, p=0.04, respectively). These findings suggest that co-infection by HTLV-I or II in Bahia, Brazil, may modify the clinical course of HIV-1 infection.