Prevalence, risk factors and genetic characterization of human T-cell lymphotropic virus types 1 and 2 in patients infected with human immunodeficiency virus type 1 in the cities of Ribeir?o Preto and S?o Paulo

摘要

The aim of this study was to define the prevalence of human T cell lymphotropic virus types 1 and 2 in patients who were positive for human immunodeficiency virus type 1 in the State of São Paulo, Brazil. We evaluated 319 individuals infected with HIV type 1 who were attended at specialized clinics in two cities (Ribeirão Preto and São Paulo). The patients were interviewed and tested for antibodies against HTLV types 1 and 2 (Orthoâ HTLV-1/HTLV-2 Ab-Capture enzyme immunoassay). Direct DNA sequencing of polymerase chain reaction products from the tax region of HTLV type 2 and the long terminal repeat region of HTLV types 1 and 2 were performed to differentiate and determine the subtypes. The overall prevalence of anti-HTLV type 1 and 2 antibodies was 7.5% (24/319; 95% CI: 5.2-11.5). HTLV type 1 and 2 infection was associated with a history of injected drug use and with antibodies for hepatitis C virus (p 0.001), but not with age (p = 0.2), sex (p = 0.9), sexual behavior or serological markers for sexually transmitted diseases (anti-Treponema pallidum, anti-human herpesvirus type 8 or anti-hepatitis B virus antibodies) (p 0.05). HTLV DNA was detected in 13 out of 24 samples, of which 12 were characterized as HTLV subtype 2c and one as HTLV subtype 1a. Among the 12 HTLV type 2 samples, seven were from injected drug users, thus indicating that this route is an important risk factor for HTLV type 2 transmission among our population infected with HIV type 1.