Interim vaccine effectiveness against influenza virus among outpatients, France, October 2025 to January 2026
Université de Lille · Hospices Civils de Lyon · +18 more institutions
Abstract
In Europe, the 2025/26 seasonal influenza epidemic started in October 2025. Co-circulation of A(H3N2) and A(H1N1)pdm09 was observed in several countries including France. We estimated early vaccine effectiveness (VE) against influenza virus in French outpatients (5,451 positives/18,816 negatives). A significant VE across all age groups was measured: 28% (95% CI: 17-37) for those aged ≥ 65 years, 45% (95% CI: 36-53) for 18-64-year-olds and 57% (95% CIs: 29-74) for 0-17-year-olds. Reinforcing vaccination uptake is warranted.
Citation impact
- FWCI
- 130.04
- Percentile
- 100%
- References
- 14
Authors
18- ADAllan De ClercqCorresponding
Université de Lille, Hospices Civils de Lyon
- FBFrançois Blanquart
Centre National de la Recherche Scientifique, Inserm, Collège de France, Université Paris Sciences et Lettres, Centre Interdisciplinaire de Recherche en Biologie
- VVVincent Vieillefond
Honeywell (France)
- BVBenoît Visseaux
Virbac (France)
- AJAlexandra Jacques
Georgia Tech Lorraine, Houillères de Lorraine
Topics & keywords
- Interim
- Vaccination
- Influenza vaccine
- Seasonal influenza
- Live attenuated influenza vaccine
- Virus
- Good health and well-being