AIDS prevention is evolving. Along with the condom and screening, treatment has become a prevention tool in its own right. Today, treatments allow people living with HIV to live longer in good health and block HIV transmission.

What is HIV?

HIV (Human Immunodeficiency Virus) is a virus that progressively attacks the immune system and that is transmitted by:

  • sperm and vaginal secretions during sexual intercourse without a condom
  • blood when needles are exchanged among injecting drug users
  • from mother to child during pregnancy, childbirth and breastfeeding.

What is AIDS?

AIDS (Acquired Immunodeficiency Syndrome) occurs in the final stage of HIV infection. At this stage, the immune system is no longer able to defend the body. A person whose immune system is no longer able to defend the body is said to be immunosuppressed. 

How does the HIV virus work?

The HIV virus multiplies in the body and invades cells of the immune system, CD4 T lymphocytes. These cells play a fundamental role in defending the body against microbes. 

The destruction of CD4 T lymphocytes weakens the immune system, which can no longer fulfil its role of fighting infections.

The immune system then becomes very vulnerable to opportunistic infections: microbes that do not cause disease in a healthy person trigger an often severe disease in the immunosuppressed.

When opportunistic infections or HIV-related cancers occur, we speak of Acquired Immunodeficiency Syndrome (AIDS).

What is a HIV positive person?

An HIV-positive person is a person living with HIV: his or her blood test (serum) is reactive to HIV antibodies, made in response to a HIV infection.

In the absence of treatment, the ultimate stage of HIV infection, AIDS, can occur 10 to 15 years after infection. 

People with AIDS are all HIV-positive, but not all HIV-positive people have AIDS!

DID YOU KNOW? It was in 1981 that the United States reported the first signs of a rare disease. The AIDS virus was isolated in 1983 by a team of French researchers. In 2008, the team of Pasteur researchers was awarded the Nobel Prize in Medicine.

The latest report is available in French or in Dutch 

Sciensano has been responsible for monitoring HIV and AIDS in Belgium since 1985. This surveillance makes it possible to assess the number of people infected with HIV and the proportion of those with AIDS.

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