HIV prevention is evolving. Along with condom use 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 prevent sexual transmission of HIV.

What is HIV?

HIV (Human Immunodeficiency Virus) is a virus that progressively attacks the body’s immune system. 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 infections and diseases. 
There is currently no curative treatment for HIV. Once people get HIV, they have it for life. But with proper medical care and antiretroviral treatment, HIV can be controlled. If HIV is not treated, it leads to AIDS (acquired immunodeficiency syndrome).

How is HIV transmitted? 

The most common ways of getting HIV are: 

  • Having vaginal or anal sex with someone who has HIV without using a condom
  • Sharing needles, syringes or other drug injection equipment with someone who has HIV

HIV might also be transmitted from a mother living with HIV to her baby during pregnancy, birth, or breastfeeding. However, it is very uncommon in Belgium because of advances in HIV prevention and treatment. 
HIV may also be spread through transfusion of infected blood or organ transplantation. However, due to the screening of blood for evidence of HIV infection, the risk of acquiring HIV through blood transfusion or organ transplantation is extremely low in Belgium.

What is AIDS?

AIDS (Acquired Immunodeficiency Syndrome) occurs in the late stage of HIV infection. At this stage, the immune system is no longer able to defend the body. People with AIDS can get an increasing number of opportunistic infections or other serious illnesses which will lead to death without HIV treatment. 

Living with HIV

A person who has an HIV infection is a person living with HIV: his or her blood test (serum) is reactive to HIV antibodies, made in response to an HIV infection. There is no cure for HIV: once a person has HIV, it is for life. But with proper medical care, HIV can be controlled. HIV treatment is often called antiretroviral therapy. People with HIV who get effective HIV treatment can live long, healthy lives and prevent sexual transmission of HIV to their partners.

How is HIV spread across the world?

There are cases of HIV present in every country of the world, but the distribution of these cases is far from being homogenous. Sub-Saharan Africa is the region most heavily affected, followed by Asia and the Pacific. In Europe, it concerns a concentrated epidemic with regional disparities in terms of infection rates and populations at increased risk.

Who is mostly affected in Belgium?

Since the start of the HIV epidemic in Belgium in 1985, two key populations have been particularly affected, namely men who have sex with men of Belgian nationality, and heterosexual men and women originating from Sub-Saharan Africa. In recent years, however, given the declining trend in diagnoses in these key populations, the proportion of populations with different profiles has become relatively larger, so the epidemic in Belgium is now more diversified.

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 allows to monitor the number of people infected with HIV and their care.

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