Vaccine Composition 2025-2026 US Influenza Season
On March 13, 2025, the FDA made recommendations to vaccine manufacturers for the virus strains to be used in influenza (flu) vaccines for the 2025-2026 U.S. flu season following a thorough and comprehensive review of U.S. and global surveillance data. The recommendations are similar to the previous year’s strain selection.
To inform the selection of the flu virus strains, the FDA convened a meeting of scientific and public health experts from the FDA, Centers for Disease Control and Prevention and Department of Defense for this in-depth discussion. During the meeting, these federal partners collaboratively evaluated and analyzed U.S. and global surveillance data related to the epidemiology and antigenic characteristics of flu viruses currently circulating.
Trivalent, Egg-Based Vaccines
- A/Victoria/4897/2022 (H1N1)pdm09-like virus;
- A/Croatia/10136RV/2023 (H3N2)-like virus; and
- B/Austria/1359417/2021 (B/Victoria lineage)-like virus.
Trivalent, Cell- or Recombinant-Based Vaccines
- A/Wisconsin/67/2022 (H1N1)pdm09-like virus;
- A/District of Colombia/27/2023 (H3N2)-like virus; and
- B/Austria/1359417/2021 (B/Victoria lineage)-like virus.
Egg Allergies
- All persons aged ≥6 months with egg allergy should receive influenza vaccine. Any influenza vaccine (egg based or nonegg based) that is otherwise appropriate for the recipient’s age and health status can be used.
- It is no longer recommended that persons who have had an allergic reaction to egg involving symptoms other than urticaria should be vaccinated in an inpatient or outpatient medical setting supervised by a health care provider who is able to recognize and manage severe allergic reactions if an egg-based vaccine is used
- Egg allergy alone necessitates no additional safety measures for influenza vaccination (beyond those recommended for any recipient of any vaccine, regardless of severity of previous reaction to egg)
- All vaccines should be administered in settings which personnel and equipment needed for rapid recognition and treatment of acute hypersensitivity reactions are available
Timing
For most persons who need only 1 dose of influenza vaccine for the season, vaccination should ideally be offered during September or October. Vaccination can continue after October and throughout influenza season as long as influenza viruses are circulating and unexpired vaccine is available.