Recommended composition of influenza virus vaccines for use in the 2025 southern hemisphere influenza season

Overview

For trivalent vaccines for use in the 2025 southern hemisphere influenza season, the WHO recommends the following:  

Egg-based vaccines 

• 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.

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; and

• 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.