Infection with the tick-borne encephalitis virus (TBEV) has been on the list of notifiable diseases in France since May 2021. In the light of the data collected, the Haut Conseil de la Santé publique (HCSP or French High Council of Public Health) updates its opinion of July 23, 2020 on the risks derived from blood products and grafts contaminated by TBEV.

The HCSP takes into account that this arbovirus, still in a dynamic phase of progression, mainly concerns the “Grand-Est”, “Auvergne-Rhône-Alpes”, and “Bourgogne Franche-Comté” regions in mainland France. The principal vector remains the Ixodes ricinus species, but cases associated with ticks of the Dermacentor genus have also arised. Among the circumstances of exposure, it appears that the consumption of raw milk and cheeses made from raw milk plays a more important role than previously recognized.

The genomic and serological biological tests described in the opinion of July 23, 2020 for the virological qualification of donations of human body products remain accurate. The periods (March to November) and precautions for securing products derived from the human body do not change.

Moreover, apart from an already old case that seems very probable, the human-to-human transmission of TBEV through breast milk has been neither confirmed nor invalidated by subsequent research. Breast milk donations for therapeutic use are systematically pasteurized, which very effectively suppresses the infectivity of TBEV.

Finally, the HCSP takes advantage of this referral to recall the importance of mandatory reporting of TBEV infections and recommends better information for the public and healthcare professionals about this increasing risk and notably on the use of prevention measures, including vaccination of exposed professionals.