HIV in Canada: A primer for service providers

Heterosexual transmission

Key Points

  • Heterosexual transmission accounted for an estimated 33% of new HIV infections in 2014.
  • HIV incidence may be decreasing in Canadians exposed to HIV through heterosexual sex since 2011.
  • Heterosexual transmission accounted for an estimated 31% of all Canadians living with HIV in 2014 (prevalence).
  • People from countries where HIV is endemic are over-represented in the Canadian HIV epidemic.

Heterosexual transmission occurs in people from both HIV-endemic countries and non-HIV-endemic countries in Canada. For the purpose of HIV surveillance, HIV-endemic countries are generally defined as those that have an adult prevalence of HIV that is 1% or greater and one of the following:

  • 50% or more of HIV diagnoses are attributed to heterosexual transmission;
  • the male-to-female ratio of people living with HIV is 2:1 or less; or
  • the HIV prevalence is 2% or greater among females receiving prenatal care.

Examples of regions where HIV is considered endemic include sub-Saharan Africa and the Caribbean.

The 2014 estimates of HIV prevalence and incidence indicate that heterosexual exposure to HIV represents a substantial proportion of the HIV epidemic in Canada.

An estimated 839 new HIV infections (33% of all new infections in Canada) were attributed to heterosexual contact in 2014. This estimate includes an estimated 358 new infections (14%) attributed to heterosexual sex in people from a country where HIV is endemic and 481 (19%) new infections attributed to heterosexual sex in people from a country where HIV is not endemic.

HIV incidence has declined slightly in heterosexual populations in Canada since 2011. In 2011, the estimated number of new HIV infections attributed to heterosexual contact was 927.

People from HIV-endemic countries (residing in Canada) are 6.3 times more likely to get HIV than people born in Canada and other non-endemic countries in 2014. According to national 2014 estimates, there were 40.3 new HIV infections for every 100,000 people from HIV-endemic countries who were residing in Canada. This compares to only 6.4 new HIV infections per 100,000 people born in Canada or non-endemic countries.

Heterosexual transmission accounted for an estimated 31% of all Canadians living with HIV in 2014 (23,700 people). Of these, 11,360 people (15% of all people living with HIV) were from a country where HIV is endemic (primarily countries in sub-Saharan Africa and the Caribbean).

According to 2014 national HIV estimates, 28% of HIV-positive people whose infection is attributable to a heterosexual exposure remain undiagnosed. This represents an estimated 6,636 people.

The epidemiological picture for people from countries where HIV is endemic includes transmission through heterosexual contact only and does not include people exposed to HIV through injection drug use or men who have sex with men who are from an HIV-endemic country.

The communities of people from countries where HIV is endemic are diverse, reflecting variations in historical backgrounds, language and cultural traditions. These communities are disproportionately affected by many social, economic and behavioural factors (determinants of health) that not only increase their vulnerability to HIV but may also act as barriers to accessing prevention, testing, treatment, and care and support programs.

Resources

The epidemiology of HIV in Canada – CATIE fact sheet

Summary: Estimates of HIV Incidence, Prevalence and Proportion Undiagnosed in Canada, 2014 – Public Health Agency of Canada (PHAC)

HIV/AIDS Epi Updates. Chapter 13: HIV/AIDS in Canada among people from countries where HIV is endemic – Public Health Agency of Canada

HIV/AIDS in Canada – CATIE infographic

People living with HIV in Canada – CATIE infographic

New HIV infections in Canada – CATIE infographic

Where is HIV hitting hardest? – CATIE infographic

HIV in Canada – PHAC infographic

Sources

  1. Public Health Agency of Canada. Summary: Estimates of HIV Incidence, Prevalence and Proportion Undiagnosed in Canada, 2014. Ottawa: Surveillance and Epidemiology Division, Professional Guidelines and Public Health Practice Division, Centre for Communicable Diseases and Infection Control, PHAC; 2015. Available at: http://www.catie.ca/en/resources/summary-estimates-hiv-incidence-prevalence-and-proportion-undiagnosed-canada-2014
  2. Public Health Agency of Canada. HIV/AIDS Epi Updates Chapter 1: National HIV Prevalence and Incidence Estimates for 2011. Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, 2014. Available at: http://www.catie.ca/en/resources/hivaids-epi-update-chapter-1-national-hiv-prevalence-and-incidence-estimates-2011-0