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 does Sciensano do?
Sciensano has been responsible for monitoring HIV and AIDS in Belgium since 1985. This surveillance is important because it allows us to assess the number of people infected with HIV and the proportion of those with AIDS. It is based on:
- HIV diagnostics
- the Belgian HIV cohort.
The clinical, biological and therapeutic data collected contribute to a better understanding of the evolution of HIV infection and associated factors, the monitoring of HIV-related morbidity and mortality and the estimation of epidemiological indicators on the care of people living with HIV.
This data is then sent to Sciensano, which analyzes them and draws up an annual report (see the bottom of this page) that takes stock of the situation of HIV and AIDS in Belgium the year before. This epidemiological assessment then allows the authorities to draw conclusions and reassess the policy on HIV/AIDS.
Data on the AIDS situation and HIV diagnostics in Belgium come from two sources:
- registration and notification of AIDS patients by clinicians
- recording of HIV status diagnostics by the reference laboratories performing the confirmatory tests.
They are in fact the same patients, but taken into account at different stages of the disease. AIDS patients are all HIV-positive, but most HIV-positive people have not reached the AIDS stage.
In Belgium there are 7 AIDS Reference Laboratories recognized by the Federal Public Service for Public Health, Food Chain Safety and the Environment.. Their mission is, among others, to:
- perform the confirmatory tests on sera found positive during a screening test
- measure the viral load of people living with HIV under medical supervision
- collect epidemiological data (age, sex, nationality, behavior, etc.).
As in other European countries, HIV surveillance in Belgium is based on monitoring diagnostics of HIV infection. This surveillance has a limit: it does not represent the actual incidence of HIV infection. New HIV diagnostics recorded include patients recently infected as well as patients infected for several years, but patients who are unaware of their infection are not included.
Indeed, after infection with HIV, several years elapse before the onset of symptoms. Early diagnosis is influenced by factors such as the rate of progression of the disease, the availability of HIV testing services and the frequency of screening.
Estimating the incidence of HIV and the number of people living with HIV is important for a better understanding of the HIV epidemic in Belgium.
HIV Cohort: data from HIV-infected patients under medical supervision
Following the introduction of antiretroviral therapy in 1996, the life expectancy of people living with HIV has improved dramatically, and the population of people living with HIV under medical supervision has increased more rapidly.
In order to be able to describe and study this aspect of this epidemiological evolution, data relating to the medically monitored population are collected:
- by the AIDS reference laboratories that regularly measure the viral load of people living with HIV under medical supervision
- by the AIDS reference centers that record the treatment data and the immunologic evolution of more than 75% of patients living with HIV under medical supervision.
These two data sources make it possible to obtain a complete picture of the population infected with HIV under medical supervision in Belgium.