HIV prevalence and risk behaviour among men who have sex with men (MSM) in Vancouver, Canada
R. Gustafson1, D. Moore2, S. Kanters2, R. Hogg2, T. Trussler3, R. Marchand3, P. Banks4, M. Kwag1, M. Comptom1, A. Schilder2, M. MacGuire5, S. Ogunnaike-Cooke5, G. Jayaraman5, M. Perrin5, T. Wong5, C. Archibald5, W. Michelow2, M. Gilbert6, The Man Count Study Team
1Vancouver Coastal Health, Vancouver, Canada, 2BC Centre for Excellence in HIV/AIDS, Vancouver, Canada, 3Community Based Research Centre, Vancouver, Canada, 4Health Initiative for Men, Vancouver, Canada, 5Public Health Agency of Canada, Ottawa, Canada, 6BC Centre for Disease Control, Vancouver, Canada
Background: The majority of HIV infections in Canada occur among MSM. We describe the sero-prevalence and HIV risk behaviour of participants in a survey of MSM in Vancouver, Canada.
Methods: Participants were recruited from August 1, 2008 to February 28, 2009, through community venues catering to MSM. Men aged ≥ 18 years completed a self-administered questionnaire and provided a dried blood spot (DBS) for HIV and other STI testing. We describe responses from men who were HIV-negative on both self-report and DBS and from men who were HIV positive by both measures.
Results: 1169 participants completed questionnaires and 1139 (97.4%) provided DBS samples. The majority (75%) reported European/North American ethnicity; 6.6% Asian, 3.5% Aboriginal and 15% other. 208(18.1%) were HIV positive by DBS of whom 87% also self reported being positive. HIV sero-positivity by DBS increased with age; from 6.8% for men 18-25 years; 18% for men 26-35; 35% for men 36-45; and 40% for men aged>45 years. 91.4% of HIV-negative and 90.1% of HIV-positive men were sexually active in the previous six months. Of these, 15.2% of HIV negative men and 33.5% of HIV-positive reported having had unprotected anal sex with someone of unknown or discordant sero-status. Both groups of men reported taking measures to reduce the risk of HIV transmission/ acquisition, including sero-sorting (39.5% of negatives; 51.3% of positives); not ejaculating in their partner or vice-versa (43.0% of negatives; 47.3% of positives) and strategic positioning (34.9% of negatives; 36.0% of positives). 81.0% of HIV-negative men thought it was unlikely or very unlikely that they would acquire HIV during their lifetime.
Conclusion: In this sample of MSM in Vancouver, HIV prevalence was high and increased with age. HIV risk behaviour as well as measures to mitigate this risk are commonly reported among both HIV-positive and HIV-negative men.