The epidemiology of HIV in females

This fact sheet provides a snapshot of the HIV epidemic among females in Canada. 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 a population-specific surveillance system (I-Track), HIV and AIDS in Canada: Surveillance report to December 31st, 2014, and the Summary: Estimates of HIV prevalence and incidence in Canada, 2014 published by the Public Health Agency of Canada (PHAC).  More information can be found in the section “Where do these numbers come from?” at the end of the fact sheet.

Females represent just over 50% of the Canadian population.1

According to 2011 national HIV estimates, there are 17,377,018 females in Canada. This represents just over 50% of the Canadian population.

There were an estimated three new HIV infections for every 100,000 females in Canada in 2014 (incidence).1,2*

According to 2014 national HIV estimates:

  • The HIV incidence rate was 3 per 100,000 females.
  • The HIV incidence rate was 12 per 100,000 males.
  • Males are four times more likely to get HIV than females.

*Incidence rates were calculated using 2011 census data from Statistics Canada.

The number of new HIV infections has remained relatively stable among females since 2011 (incidence).2

According to 2014 national HIV estimates, 595 new HIV infections (23% of all new HIV infections) occurred in females compared to an estimated 663 new infections (24%) in 2011.

New HIV infections in females are mainly attributable to heterosexual sex and injection drug use.2

According to 2014 national HIV estimates:

  • 79% of new HIV infections among females were attributed to heterosexual sex .
  • 21% of new HIV infections among females were attributed to injection drug use.

Females aged 30 to 39 had the highest number of new HIV diagnoses.3

According to 2014 national surveillance data, females aged 30 to 39 had the highest proportion of new HIV diagnoses (37%), followed by females aged 20 to 29 (30%), females aged 40 to 49 (18%), females aged 50 and over (9%), females aged 15 to 19 (4%), and finally girls under the age of 15 (2%).

Among females, the majority of new HIV diagnoses were among those identified as Black, Aboriginal and White.3

According to 2014 national surveillance data:

  • 36% of new HIV diagnoses in women were identified as Black.
  • 31% of new HIV diagnoses in women were identified as Aboriginal.
  • 24% of new HIV diagnoses in women were identified as White.

One quarter of all people living with HIV in Canada are females (prevalence).1,2*

According to 2014 national estimates:

  • 16,880 females were living with HIV.
  • 22% of all people living with HIV were female.
  • The estimated prevalence rate in Canada was 97 per 100,000 females (compared to 364 per 100,000 males).

*Incidence rates were calculated using 2011 census data from Statistics Canada.

Federally incarcerated females have higher rates of HIV than incarcerated males.4

According to a national survey of federal prisoners conducted in 2007:

  • 8% of females reported being HIV positive, compared to only 5% of males.
  • 12% of Aboriginal females reported being HIV positive, compared to only 3% of Aboriginal males.

Approximately 10% of females who inject drugs are living with HIV and 59% have evidence of a current or past hepatitis C infection.5

According to the I-Track surveillance system (2010–2012):

  • 10% of females who injected drugs in the previous six months were HIV-positive (compared to 12% of males).
  • 59% of females who injected drugs in the previous six months had evidence of a current or past hepatitis C infection (compared to 58% of males).
  • 96% of females who self-report they are HIV positive are under the care of a doctor for their HIV (compared to 94% of males).
  • 56% of females who self-report they are HIV positive are currently taking prescribed HIV drugs (compared to 75% of males).
  • 46% of females who self-report they are hepatitis C positive are under the care of a doctor for their hepatitis C (compared to 49% of males).
  • 7% of females who self-report they are hepatitis C positive are currently taking prescribed hepatitis C drugs (compared to 11% of males)

1% of babies born to HIV-positive mothers in Canada have HIV.3

According to the Canadian Perinatal HIV Surveillance Program:

  • Between 1984 and 2014, 4,279 infants were identified as being exposed perinatally to HIV.
  • 233 infants were born to mothers with HIV in 2014 (up from 207 in 2013). Only two of these infants (1%) were confirmed HIV positive. 
  • 97% of HIV-positive mothers received HIV drug treatment in 2014, which significantly reduces the risk of HIV transmission from mother to child.

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 a population-specific surveillance system (I-Track), the HIV/AIDS Epi Updates Chapter 1: National HIV Prevalence and Incidence estimates for 2011, and HIV and AIDS in Canada: Surveillance report to December 31st, 2013 published by the Public Health Agency of Canada (PHAC).

Routine HIV reporting

Healthcare providers are required to report HIV diagnoses to their local public health authorities. Each province/territory then compiles this information and provides it to PHAC. Sometimes additional information is also collected and sent to PHAC, such as information about a person’s age, gender, ethnicity, exposure category (the way the person may have acquired HIV) and laboratory data such as the date of the HIV test.

These statistics are compiled by PHAC and published annually in HIV/AIDS surveillance reports. The most recent data (up to December 31, 2014) can be viewed at http://www.catie.ca/en/resources/hiv-and-aids-canada-surveillance-report-december-31-2014

Limitations—These data represent the number of cases reported to PHAC by each province/territory. Reported cases do not truly represent the prevalence or incidence of HIV because these statistics do not include HIV-positive individuals who have not been tested for HIV. Other limitations include reporting delays (the time between the diagnosis of HIV or AIDS and when it is reported to PHAC) and under-reporting (no report is made to the local public health authority by the healthcare provider). Caution should be used in interpreting race/ethnicity data due several factors including underreporting and challenges in determining race/ethnicity.

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 modelling, 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 2014. The next set of estimates will be available in 2018 and will pertain to the year 2017.

Population-specific surveillance

As part of the Federal Initiative to Address HIV/AIDS in Canada, PHAC monitors trends in HIV prevalence and associated risk behaviour indicators 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.

I-Track is the national surveillance system of people who inject drugs. Through this surveillance system, information is collected directly from people who inject drugs, using a questionnaire and a biological specimen sample for HIV and hepatitis C testing. The statistics provided in this fact sheet are for the years 2010 to 2012 from participating I-Track sites. Because the system only recruits voluntary participants from selected urban sites, the results do not represent all people who inject drugs across Canada.

National Inmate Infectious Diseases and Risk-Behaviours Survey

A self-administered questionnaire was developed by Correctional Services Canada in collaboration with PHAC and inmates. A random sample of males and females in federal penitentiaries were invited to voluntarily complete the questionnaire. In total, 3,370 inmates across Canada completed the questionnaire in 2007.

Canadian Perinatal HIV Surveillance Program

The Canadian Perinatal HIV Surveillance Program collects information on infants born to females living with HIV in Canada.

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, for their helpful comments and expert review of CATIE epidemiology fact sheets.

References

Author(s): Challacombe L

Published: 2015