Men who have sex with men (MSM) have a disproportionate burden of HIV infection worldwide. In Colombia, the prevalence of HIV in MSM is ~ 43 times higher than in the general population (17% vs. 0.4%). This study determined the sexual behaviors, HIV serostatus, and associated factors with condomless sexual practice with both regular and casual partners in 92 MSM from Medellín, Colombia. The subjects were recruited through a community-based approach, and the data were collected by a structured survey and in-depth interviews. Participants were classified into three groups according to the number of sexual partners in the last three months, to compare the sociodemographic conditions and sexual behaviors. Univariate analysis was described by absolute and relative frequencies; bivariate analysis and multivariate logistic regression were used to compare the groups and to explore the associated factors with condomless sexual practice. The overall HIV estimated prevalence was 4.3%, while the estimated prevalence for MSM with > 10 sexual partners in the last three months was 14.8%. This last group showed higher average age, higher percentage of subjects who have had sex with people living with HIV, and increased frequency of previous sexually transmitted infections. Having condomless sex with casual partners was associated with the number of sexual partners in the last three months. This study demonstrates that Colombian MSM continue to have a high risk of HIV infection/transmission and reinforce the need to implement adequate prevention programs, PrEP and guarantee access to treatment for people living with HIV.

男男性行为者 (MSM) 在世界范围内承受着不成比例的 HIV 感染负担。在哥伦比亚，MSM 中的 HIV 流行率是普通人群的 43 倍（17% 对 0.4%）。本研究确定了来自哥伦比亚麦德林的 92 MSM 的性行为、HIV 血清状况以及与常规和临时伴侣不使用安全套的性行为相关的因素。通过基于社区的方法招募受试者，并通过结构化调查和深度访谈收集数据。参与者根据过去三个月的性伴侣数量分为三组，以比较社会人口状况和性行为。单变量分析用绝对频率和相对频率来描述；双变量分析和多变量逻辑回归用于比较各组并探讨与无安全套性行为的相关因素。总体 HIV 估计流行率为 4.3%，而过去三个月中性伴侣超过 10 人的 MSM 估计流行率为 14.8%。最后一组显示出更高的平均年龄，与艾滋病毒感染者发生性关系的受试者比例更高，并且以前性传播感染的频率更高。与临时伴侣进行无安全套性行为与过去三个月的性伴侣数量有关。这项研究表明，哥伦比亚 MSM 仍然具有很高的 HIV 感染/传播风险，并强调需要实施适当的预防计划、PrEP 并保证 HIV 感染者获得治疗。