Risk behaviours and HIV infection among men having sexual relations with men: Baseline characteristics of participants in the Omega Cohort study, Montreal, Quebec, Canada

Objective: To describe characteristics of men having sex with men (MSM) par ticipating in the Omega Cohort, to describe HN-positive participants at bas eline interview, and to estimate HN incidence. Methods: The Omega Cohere is a study on the incidence and psychosocial dete rminants of: HIV infection among MSM living in Montreal. MSM complete a que stionnaire and are tested for HIV every six months. Results During the previous six months, 31% and 12% of 810 participants (me an age=33 reported unprotected anal sa:with regular and casual partners, re spectively. Eight participants (0.98%) were HIV-infected at baseline line. HIV incidence was 0.89 per 100 person years (7/787 person-years) [95% confi dence interval: 0.36-1.83]. Conclusion: A significant proportion of participants reported current risk, behaviours. respite this, HN incidence is relatively low. It rant to targe t MSM who do not practice safe sex and to encourage those practicing sex to sustain these behaviours.