Recommended composition of influenza virus vaccines for use in the 2026 southern hemisphere influenza season

26 September 2025

| Technical document

Recommended composition of influenza virus vaccines for use in the 2026 southern hemisphere influenza season

Download (391.9 kB)

Overview

For trivalent vaccines for use in the 2026 southern hemisphere influenza season, the WHO recommends the following:

Egg-based vaccines

• an A/Missouri/11/2025 (H1N1)pdm09-like virus;

• an A/Singapore/GP20238/2024 (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/Missouri/11/2025 (H1N1)pdm09-like virus;

• an A/Sydney/1359/2024 (H3N2)-like virus; and

• a B/Austria/1359417/2021 (B/Victoria lineage)-like virus

Consistent with previous four WHO recommendations since September 2023, it remains the opinion of the WHO influenza vaccine composition advisory committee that the inclusion of a B/Yamagata lineage antigen is no longer warranted.

Quadrivalent vaccines, where the transition to trivalent vaccines is not yet complete, contain a 4th component – a B/Yamagata lineage virus (B/Phuket/3073/2013-like virus).

There will no longer be updated recommendations for the B/Yamagata lineage component.

Overview

Related links: