The epidemiology of HIV in gay men and other men who have sex with men

This fact sheet provides a snapshot of the HIV epidemic in Canada among gay men and other men who have sex with men (MSM). It is one of a series of fact sheets on the epidemiology of HIV and hepatitis C.

All epidemiological information is approximate, based on the best available data. Most of the data in this fact sheet come from research studies, a population-specific surveillance system (M-Track) or the 2011 Estimates of HIV prevalence and incidence in Canada published by the Public Health Agency of Canada (PHAC). More information about these data sources can be found in the section “Where do these numbers come from?” at the end of the fact sheet.

Gay men and other men who have sex with men are at risk of HIV and hepatitis C.

MSM are at risk of HIV if they:

  • have unprotected anal or oral sex (sex without a condom);
  • borrow non-sterile syringes/needles to inject drugs; or
  • borrow non-sterile equipment to prepare the drug for injection.

Research also tells us that:

  • HIV-positive MSM may be at risk of becoming co-infected with hepatitis C if they have unprotected anal sex.
  • MSM who borrow non-sterile syringes, needles and/or equipment used to inject drugs are at risk of hepatitis C.

Approximately 2.1% of Canadian men self-identify as gay or bisexual.1

In a national health survey, 2.1% of Canadian men aged 18 to 59 self-identified as gay or bisexual.1 If applied to the number of men in Canada aged 18 and older,2 this means that approximately 247,000 Canadian men identify as gay or bisexual. However, it is important to note that this may underrepresent the number of MSM in Canada as there may be additional men who engage in sex with men but do not consider themselves to be gay or bisexual.

MSM may engage in sexual practices that put them at risk of acquiring HIV.3

It is difficult to know how many MSM engage in sexual behaviours that place them at risk of acquiring HIV because for many people, their sexual practices are private, sensitive topics. The best evidence we have comes from a population-specific surveillance system (M-Track) that has been established in specific regions of Canada.

Different types of sexual behaviours can place a man at risk for HIV (for example, having unprotected sex with casual partners). Just over three-quarters (77%) of M-Track participants reported sex with at least one casual partner in the past six months. And half of all participants reported inconsistent condom use with casual partners during receptive anal sex in the past six months. This varied by location across Canada:

  • In Victoria, 57% reported inconsistent condom use with casual partners in the past six months during receptive anal sex.
  • In Winnipeg, 47% reported inconsistent condom use with casual partners in the past six months during receptive anal sex.
  • In Toronto, 51% reported inconsistent condom use with casual partners in the past six months during receptive anal sex.
  • In Ottawa, 44% reported inconsistent condom use with casual partners in the past six months during receptive anal sex.
  • In Montreal, 51% reported inconsistent condom use with casual partners in the past six months during receptive anal sex.

Among MSM, between 11% and 23% are living with HIV.3,4

According to M-Track, HIV prevalence among MSM in Canadian cities ranges from approximately 11% to 23%. The HIV prevalence rates are:

  • 18% in Vancouver
  • 14% in Victoria
  • 19% in Winnipeg
  • 23% in Toronto
  • 11% in Ottawa
  • 13% in Montreal

Rates of hepatitis C infection among HIV-positive MSM are relatively high.3

According to M-Track:

  • 5% of MSM had evidence of either a current or past hepatitis C infection. Rates ranged from 2% to 19% in different parts of Canada.
  • Up to 2% of MSM are co-infected with HIV and hepatitis C.
  • Among MSM who are HIV positive, 14% also had evidence of a current or past hepatitis C infection.

Men having sex with men may have accounted for an estimated 35,490 people living with HIV (prevalence) in 2011.5

According to 2011 national HIV estimates, men having sex with men may have accounted for an estimated 35,490 people living with HIV. This includes 33,330 people (47% of people living with HIV) whose HIV status was attributed to sex between men and an additional 2,160 men (3%) whose HIV infection may have been due to either injection drug use or sex between men since they reported both behaviours at testing.

An estimated one in five men whose HIV status is attributed to sex with another man is unaware of his HIV infection.5

According to 2011 national HIV estimates, 20% of men whose HIV status was attributed to sex between men remain undiagnosed. This represents an estimated 6,666 men.

It is estimated that half of all new HIV infections in 2011 in Canada (incidence) may have been attributable to men having sex with men.5

According to 2011 national HIV estimates:

  • 1,480 new HIV infections were attributable to sex between men (47% of all new infections). This is similar to the estimated 1,470 new infections attributable to men having sex with men in 2008.
  • 80 new HIV infections were attributable to either injection drug use or sex between men (3% of all new infections). This estimate is similar to the estimated 90 new infections attributed to either injection drug use or men having sex with men in 2008.

Only two-thirds of MSM who are aware of their HIV infection are currently on HIV treatment.3

According to M-Track:

  • 66% of MSM who are aware of their HIV infection are currently taking prescribed drugs for their HIV.

Key definitions

HIV prevalence—the number of people who are living with HIV at a point in time. Prevalence tells us how many people have HIV.

HIV incidence—the number of new HIV infections in a defined period of time (usually one year). Incidence tells us how many people are getting HIV.

Where do these numbers come from?

All epidemiological information is approximate, based on the best available data. Most of the data in this fact sheet come from research studies, a population-specific surveillance system (M-Track) or the 2011 HIV prevalence and incidence estimates published by the Public Health Agency of Canada (PHAC).

Population-specific surveillance

As part of the Federal Initiative to Address HIV/AIDS in Canada, PHAC monitors trends in HIV prevalence and associated risk behaviours among key vulnerable populations identified in Canada through population-specific surveillance systems. These surveillance systems, also known as the “Track” systems, are comprised of periodic cross-sectional surveys conducted at selected sites within Canada.

M-Track is the national surveillance system of gay, bisexual and other men who have sex with men (MSM). For this surveillance system, information is collected directly from MSM through a questionnaire and a biological specimen collected for testing for antibodies against HIV, hepatitis C and syphilis. As of December 31, 2009, a total of six sites had participated in M-Track across Canada. M-Track was first implemented in Montreal in 2005 (via linkage with the Argus Survey). Between 2006 and 2007, four additional sites joined M-Track: Toronto and Ottawa (Lambda Survey), Winnipeg and Victoria. More than 4,500 men participated in M-Track between 2005 and 2007. In 2008, Vancouver also implemented M-Track (ManCount Survey).

Limitation—MSM from selected urban sites participated on a volunteer basis; therefore, the information presented does not represent all men who have sex with men in Canada.  

National estimates of HIV prevalence and incidence

National HIV estimates are produced by PHAC and published every three years. Estimates of HIV prevalence and incidence are produced by PHAC using statistical methods which take into account some of the limitations of surveillance data (number of HIV diagnoses reported to PHAC) and also account for the number of people living with HIV who do not yet know they have it. Statistical modeling, using surveillance data and additional sources of information, allows PHAC to produce HIV estimates among those diagnosed and undiagnosed. The most recent estimates available are for 2011. The next set of estimates will be available in 2015 and will pertain to the year 2014.

Acknowledgements

We would like to thank the Surveillance and Risk Assessment Division of the Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada and Robert Remis, MDCM, MPH, Dalla Lana School of Public Health, University of Toronto for their helpful comments.

References

Author(s): Challacombe L

Published: 2014