HIV infection, high-risk behaviors and substance use in homeless men sheltered in therapeutic communities in Central Brazil.

Homeless men present high vulnerability to HIV infection, mainly due to sexual risk behaviors and substance use. The objective was to estimate the prevalence of HIV infection, risk behaviors and substance use in homeless men. A cross-sectional study was conducted in 481 homeless men recruited in four therapeutic communities in the Goiás State, Central Brazil. All were interviewed about sociodemographic characteristics, substance use, and risk behaviors. Furthermore, all were tested for HIV. Poisson regression was used to verify factors associated with HIV infection. HIV prevalence was 1.24% (95.0% CI: 0.57 to 2.69%). Previous HIV testing (adjusted prevalence ratio [APR]: 10.0; 95.0% CI: 1.86-55.8) and years of education (APR: 0.76; 95.0% CI: 0.60-0.97) were factors associated with HIV infection. Participants had high rates of hazardous alcohol use and illicit drug use. The prevalence of HIV infection among homeless men was higher than that found in the Brazilian male population and we identified a high rate of risk behaviors for HIV among the homeless men investigated. Thus, it is necessary to expand HIV prevention measures in Brazil, such as health education, condom availability, regular HIV testing and increased testing coverage in this population, and treatment for alcohol and/or illicit drug dependence/abuse.

Risk behaviors for sexually transmitted infections in noninjecting drug users: A cross-sectional study.

The objective of this study was to investigate risk behaviors for sexually transmitted infections (STIs) in noninjecting drug users (NIDUs), using STI diagnosis history as an indicator. A cross-sectional study was conducted in 323 NIDUs of two facilities for alcohol and/or drug dependence treatment in the Goiás State, Central Brazil. All participants were interviewed about risk behaviors and STI history. Multivariable analysis was performed in order to identify predictors of STIs. Adjusted prevalence ratio (APR) with confidence intervals of 95% was obtained using a Poisson regression model. Prevalence of self-reported STIs in the previous 12 months was 25.4% (95% confidence interval [95% CI]: 21.0-30.4%). A multivariable model verified that age (APR: 1.01; 95% CI: 1.00-1.01), sexual contact with partners diagnosed with STIs (APR: 1.27; 95% CI: 1.12-1.45) and injecting drug users (IDUs) (APR: 1.14; 95% CI: 1.14; 95% CI: 1.01-1.31), exchange sex for money and/or drugs (APR: 1.12; 95% CI: 1.02-1.21), and a history of sexual violence (APR: 1.04; 95% CI: 1.04-1.32) were predictors of STIs. Elevated rates of STI history and risk behaviors were observed in NIDUs, supporting the vulnerability of this group for these infections. Public policies and health outreach should be intensified in this population, principally regular STI testing of individuals in treatment for drug dependence and their sexual partners.

High IFN-γ/IL-10 expression ratio and increased frequency of persistent human T-cell lymphotropic virus type 1-infected clones are associated with human T-cell lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis development.

BACKGROUND/AIMS: Human T-cell lymphotropic virus type 1 (HTLV-1) is a retrovirus that causes a persistent infection, and only 0.5-5% of infected individuals will develop HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Therefore, we investigated parameters to discriminate HTLV-1 asymptomatic carriers (ACs) with an increased chance to develop HAM/TSP. METHODS: We evaluated integration patterns of HTLV-1 provirus, the relative expression of HTLV-1 tax and HBZ mRNAs and of IFN-γ and IL-10 mRNAs, in addition to proviral load (PVL) levels. RESULTS: HAM/TSP patients presented a higher number of large persistent HTLV-1-carrying clones compared to ACs, and the expression of the HTLV-1 tax and HBZ genes by infected cells was detected at low levels and correlated positively with PVL. In addition, HAM/TSP patients and ACs with high PVL expressed higher levels of IFN-γ mRNA in comparison to IL-10, while ACs with low PVL presented an equilibrate IFN-γ/IL-10 ratio. CONCLUSIONS: The presence of large persistent HTLV-1-infected clones in association with viral gene expression, even at small levels, could stimulate the intense inflammatory response in HTLV-1-infected individuals. This was supported by a high ratio of IFN-γ/IL-10 relative expression in HAM/TSP patients and ACs with high PVL, indicating that these parameters could aid the identification of ACs with a high risk to develop HAM/TSP.