What are the vaccine viruses for the 2024-25 influenza season?

The 2024-25 vaccines are all trivalent (containing two influenza A and one influenza B strains). The B/Yamagata virus vaccine antigens are no longer included in influenza vaccines because B/Yamagata viruses have not been detected globally since March 2020.

The 2024-25 vaccines include a new influenza A(H3N2) component.

Egg-based influenza vaccines include:

• an A/Victoria/4897/2022 (H1N1)pdm09-like virus;
• an A/Thailand/8/2022 (H3N2)-like virus; and,
• a B/Austria/1359417/2021 (B/Victoria lineage)-like virus.

Cell culture-based or recombinant vaccines include:

• an A/Wisconsin/67/2022 (H1N1)pdm09-like virus;
• an A/Massachusetts/18/2022 (H3N2)-like virus; and,
• a B/Austria/1359417/2021 (B/Victoria lineage)-like virus.