WHO Sets Stage for Effective 2025–2026 Flu Vaccines
Global, Friday, 28 February 2025.
The WHO has set the influenza vaccine composition for the 2025–2026 season, aiming for high efficacy against evolving viruses with input from global surveillance data.
Latest Vaccine Composition Announcement
The World Health Organization (WHO) revealed its latest influenza vaccine recommendations on February 28, 2025, following an intensive four-day consultation with global experts [1]. The announcement comes at a critical time, as surveillance data from the WHO Global Influenza Surveillance and Response System (GISRS) has been carefully analyzed to ensure optimal vaccine effectiveness for the upcoming season [1].
Specific Strain Recommendations
For the 2025-2026 northern hemisphere season, WHO has recommended distinct compositions for different vaccine production methods. Egg-based vaccines will contain an A/Victoria/4897/2022 (H1N1)pdm09-like virus, an A/Croatia/10136RV/2023 (H3N2)-like virus, and a B/Austria/1359417/2021 (B/Victoria lineage)-like virus [1]. For cell culture, recombinant protein, or nucleic acid-based vaccines, slightly different strains have been selected, including an A/Wisconsin/67/2022 (H1N1)pdm09-like virus and an A/District of Columbia/27/2023 (H3N2)-like virus [1][5].
Urgent Context: Rising H5N1 Cases
These recommendations arrive amid increasing concerns about avian influenza, with the CDC reporting 70 human cases of H5N1 since April 2024 [4]. Recent developments include the first human bird flu cases in Wyoming and Ohio, confirmed as of February 25, 2025, highlighting the growing importance of robust influenza surveillance and prevention strategies [4].
Implementation and Monitoring
The Minnesota Department of Health exemplifies the comprehensive approach to influenza surveillance, utilizing multiple tracking methods including laboratory-confirmed cases and sentinel surveillance programs [2]. This multi-faceted monitoring system, combined with the WHO’s recommendations, will guide national vaccine regulatory agencies and pharmaceutical companies in developing and producing vaccines for the upcoming season [1][5].