CSL Seqirus is pleased to provide the following information for the upcoming season:
On February 28th, 2025, The World Health Organization (WHO) announced the recommendations for the viral composition of influenza vaccines for the 2025-2026 influenza season in the northern hemisphere. For both egg-based quadrivalent and cell or recombinant-based quadrivalent vaccines, the WHO recommends that:
For trivalent vaccines for use in the 2025-2026 northern hemisphere influenza season contain the following:
Egg-based vaccines
- an A/Victoria/4897/2022 (H1N1)pdm09-like virus;
- an A/Croatia/10136RV/2023 (H3N2)-like virus;
- a B/Austria/1359417/2021 (B/Victoria lineage)-like virus.
Cell culture-, recombinant protein- or nucleic acid-based vaccines
- an A/Wisconsin/67/2022 (H1N1)pdm09-like virus;
- an A/District of Columbia/27/2023 (H3N2)-like virus;
- a B/Austria/1359417/2021 (B/Victoria lineage)-like virus.
The recommendation for the B/Yamagata lineage component of quadrivalent influenza vaccines remains unchanged from previous recommendations:
- a B/Phuket/3073/2013 (B/Yamagata lineage)-like virus.
If you wish to review the WHO recommendations, please click on the link: Recommendations announced for influenza vaccine composition for the 2025–2026 northern hemisphere influenza season
CSL Seqirus is a central partner to clinicians and pharmacists, providing a range of vaccines to offer their patients and consumers innovative options.
CSL Seqirus work with leading Canadian researchers, healthcare professionals and public health leaders to advance scientific knowledge and global influenza research.
National Recommendations
NACI Seasonal Influenza Vaccine Statement