Key Points

Influenza

• A severe epidemic lasting 12 weeks (S50-2024 to S10-2025), with an “early” first peak at the very end of 2024 and a second peak in S04 and S05 of 2025. The impact was significant among people aged 65 and older, but also among those under 15. Vaccination coverage was slightly lower than in 2023–2024 and well below targets. The 2024–2025 season was characterized by the co-circulation of several types of influenza viruses.

Bronchiolitis (<2 years)

• Moderate-intensity epidemic likely linked to the immunization campaign for newborns and infants and the start of vaccination for pregnant women (between 32 and 36 weeks of gestation). The epidemic lasted for a shorter period than the previous season (8 weeks vs. 13 weeks) with an epidemic peak in S51-2024.

COVID-19

• A low-intensity autumn peak in September/October 2024 and no winter epidemic in 2024–2025

Severe cases of influenza, COVID-19 (all ages), and RSV infections (adults) in intensive care

• 205 cases reported by this sentinel surveillance system, including 145 cases of influenza, 40 cases of COVID-19 (5 influenza-SARS-CoV-2 co-infections), and 20 cases of respiratory syncytial virus (RSV) infection in adults.

Clusters of acute respiratory infections (ARI) in long-term care facilities

• 679 clusters of ARI cases in long-term care facilities reported between weeks S40-2024 and S15-2025, with influenza as the primary cause.

Mortality linked to influenza and COVID-19 (electronic death certificates)

• A sharp increase in deaths with influenza listed as a cause reported during the winter of 2024–2025.