At the beginning of the vector activity period on the 1st of June each year, the French High Council for Public Health (HCSP) updates the list of countries or regions considered to be at risk of West Nile virus (WNV) transmission for donations of human body products. This update is based on epidemiological knowledge and reports of cases over the last three years. The main arguments that prevailed in the establishment of this list for the 2021 season are:

• the low circulation of WNV in 2020 in France and in the other countries usually concerned;
• the level of entomological, veterinary (equine cases) and human surveillance in each country
• the benefit/risk analysis with regards to the intensity of population exchanges between France and other concerned countries in relation to the stocks of labile blood products.

A new criterion for a country to be removed from the list has also been introduced for countries that have had fewer than 10 human cases of WNV infection per year in a single year over the last three years (i.e. without any cases reported in the other two years).

The HCSP also renewed its recommendations by distinguishing between alerts occurring abroad and those occurring in France, and also the type of products derived from the human body: labile blood products versus organs, tissues and cells.

Finally, this statement took into account the first human case of WNV infection documented in Mayotte and reported on May 25, 2021, without recommending any specific measure for blood donation since no blood collection takes place in Mayotte and that travellers returning from this territory are temporarily excluded from donating blood due to the endemic risk of malaria. For potential organ, tissue or cell donations, the same measures as those recommended in the event of viral circulation in metropolitan France are recommended, namely virological tests on the donor combining viral genome diagnosis and serology.