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AIDS ribbon What is HIV/AIDS?

HIV - the Human Immunodeficiency Virus - is a virus that attacks the immune system, resulting in a chronic, progressive illness that leaves people vulnerable to opportunistic infections and cancers. When the body can no longer fight infection, the disease is known as AIDS, which stands for Acquired Immunodeficiency Syndrome. On average, it takes more than 10 years to progress from initial HIV infection to AIDS.

AIDS is a deadly disease that has already killed more than 25 million people around the world, according to the Joint United Nations Programme on HIV/AIDS (UNAIDS)External link. There is no cure for AIDS, and currently no vaccine against HIV infectionExternal link.

In order to be infected, the virus must enter a person's bloodstream (HIV cannot survive outside the body). HIV is transmitted from one person to another through:

  • unprotected sexual intercourse (vaginal, anal or oral)
  • shared needles or equipment for injecting drugs
  • unsterilized needles for tattooing, skin piercing or acupuncture
  • pregnancy, delivery and breast feeding (i.e., from an HIV-infected mother to her infant)
  • occupational exposure in health care settings

Despite the fact that HIV infection is largely preventable, thousands of new infections occur each year and the number of persons living with HIV in Canada is rising. The Public Health Agency of Canada estimates that 58,000 people in Canada were living with HIV infection at the end of 2005 - a 16 per cent increase from the 2002 estimate of 50,000. An estimated 27 per cent of these individuals - or 15,800 people - were believed to be unaware of their infection and thus were not seeking treatment and may have been unknowingly infecting others.

PHAC Continues to Emphasize Safer Sex for Preventing HIV Transmission

The Public Health Agency of Canada continues to emphasize that sexually active people living with HIV should practise safer sex, which includes using condoms consistently and correctly with all sex partners.

An article recently published by Switzerland’s Federal Commission for HIV/AIDS states that HIV-positive individuals on effective antiretroviral therapy may not be at risk for transmitting HIV to their sexual partners under certain circumstances, specifically no detectable viral load and the absence of other sexually transmitted infections. In the same article, the Commission acknowledges that there are no scientific data indicating that the risk of transmission in these circumstances is zero. The Public Health Agency of Canada continues to emphasize that sexually active people living with HIV should practise safer sex, which includes using condoms consistently and correctly with all sex partners.