FDA

FDA releases influenza vaccine composition for the 2025-2026 season

March 17, 2025

On March 14, FDA announced that it made recommendations to vaccine manufacturers for the virus strains to be used in influenza vaccines for the 2025-2026 U.S. flu season following a review of U.S. and global surveillance data.

Additional information:

Trivalent seasonal influenza vaccines include two influenza A subtype viruses (H1N1 and H3N2) and one influenza type B virus. Influenza virus strains were selected based on the influenza vaccine production method: egg-based and cell- or recombinant-based.

As a result of the meeting with the federal partners, FDA recommends that the trivalent formulation of egg-based influenza vaccines for the 2025-2026 U.S. influenza season contain the following:

• 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.

The agency recommends that the trivalent formulation of cell- or recombinant-based influenza vaccines for the 2025-2026 U.S. influenza season contain the following:

• an A/Wisconsin/67/2022 (H1N1)pdm09-like virus;
• an A/District of Columbia/27/2023 (H3N2)-like virus; and
• a B/Austria/1359417/2021 (B/Victoria lineage)-like virus.

FDA informed the manufacturers of approved seasonal influenza vaccines of these recommendations and says it anticipates that there will be an adequate and diverse supply of approved trivalent seasonal influenza vaccines for the 2025-2026 U.S. influenza season.

Source:

(2025, March 13). FDA. Influenza Vaccine Composition for the 2025-2026 U.S. Influenza Season. https://www.fda.gov/vaccines-blood-biologics/influenza-vaccine-composition-2025-2026-us-influenza-season