Prevalence and Risk Factors for HIV Infection in a Population of Homosexual, Bisexual, and Other Men Who Have Sex with Men in the Metropolitan Region of Chile: A Re-emerging Health Problem.

According to the most recent UNAIDS report, the number of new HIV infections has increased by 34% since 2010 in Chile, representing the largest increase in the Americas. The objective of this study was to identify factors associated with HIV prevalence among men who have sex with men (MSM) in the metropolitan region (MR) of Santiago, Chile. Cross-sectional study of MSM living in the MR, recruited using respondent-driven sampling (RDS). Participants were tested using Human Immunodeficiency virus rapid test, and reactive cases were confirmed withELISA. Participants were interviewed using a questionnaire adapted for the Chilean population. Descriptive and logistic regression analyses were then performed. All applicable ethical norms were followed in the execution of this study. The total sample consisted of 375 individuals. HIV prevalence among MSM was 17.6% overall. Among the HIV-negative men, most (71.5%) had not been tested for sexually-transmitted diseases (STIs) other than HIV in the past 12 months, and 24.1% had never been tested for HIV. Participants who had been tested for an STI other than HIV in the past 12 months had a 3.56-fold greater OR for HIV-positive status than those who had not. Conversely, having had an HIV test in the past 12 months was a protective factor against positive HIV status (OR = 0.09). The high prevalence of HIV among MSM suggests a re-emergence of the disease in Chile, and cases are specifically concentrated among young MSM. Access to sexual health care and STI testing in Chile is insufficient. Targeted prevention efforts are urgently needed as part of the Chilean national strategy to combat the spread of HIV, including community-based testing programs.