What is the purpose of monitoring blood donors?

Epidemiological monitoring of blood donors makes it possible to measure the impact of changes in selection criteria through various indicators, such as the number and characteristics of donors who test positive for HIV, syphilis, and hepatitis B and C, as well as estimates of the residual risk associated with HIV and hepatitis… As part of these new developments in access to blood donation, this surveillance has been strengthened to provide real-time monitoring of these indicators.

Established in 1992, this epidemiological surveillance is coordinated by Santé publique France in partnership with the French Blood Establishment (EFS), the Armed Forces Blood Transfusion Center (CTSA), and the National Agency for Medicines and Health Products Safety (ANSM).

The epidemiological surveillance of blood donors conducted by Santé publique France makes it possible to track the impact of changes in selection criteria on all infectious markers, particularly HIV:

• monitoring changes in the number of donors found to be HIV-positive among new donors (HIV prevalence);

• monitoring changes in the number of HIV seroconversions among known donors and donations detected as recent infections among all donors (HIV incidence);

• providing demographic and epidemiological information on donors confirmed to be HIV-positive (gender, age, donor type (new/known), geographic origin, probable mode of transmission, other markers of infection, etc.). Indeed, if an infectious marker is detected, the donor is notified and invited by the EFS or the CTSA to attend a post-donation medical interview during which this information is collected;

• Estimation of the residual risk of transmission via transfusion associated with the window period, the time between when a person becomes infected and when markers of infection become detectable by laboratory tests. This risk is currently estimated at 1 in 11.6 million donations, or one donation potentially infected with HIV every 4 years.