WHO Announces Recommendations for 2026-2027 Influenza Vaccines
The World Health Organization (WHO) has announced its recommendations for the composition of influenza vaccines for the 2026-2027 northern hemisphere influenza season. These recommendations, made following a four-day consultation examining global influenza surveillance data, are crucial for ensuring that vaccines effectively protect against circulating strains of the virus. WHO News
Why Vaccine Composition Needs Regular Updates
Influenza viruses are constantly changing, necessitating regular updates to vaccine composition. The WHO’s recommendations guide national regulatory agencies and pharmaceutical companies worldwide in developing and producing vaccines that closely match the expected circulating viruses, maximizing protection against severe illness and death. WHO News
Global Surveillance and the GISRS
The recommendations are based on data from the WHO’s Global Influenza Surveillance and Response System (GISRS), a network of collaborating centers and essential regulatory laboratories. These consultations, held twice yearly for both hemispheres, analyze data generated by GISRS and its partners. WHO News
Key Findings from the February 2026 Consultation
The recent review highlighted the emergence of a notably different variant of the A(H3N2) virus, classified as J.2.4.1 (also known as “subclade K”), which spread rapidly in August 2025. This variant contributed to an earlier start to the influenza season and higher-than-usual activity in many countries. Influenza A viruses were predominant, with other variants of A(H3N2) and A(H1N1) also recorded. Low levels of influenza B viruses (B/Victoria lineage) were detected, with no cases of B/Yamagata lineage viruses recorded since March 2020. WHO News
Recommended Vaccine Composition for 2026-2027
For the 2026-2027 northern hemisphere influenza season, the WHO recommends the following:
Egg-Based Vaccines
- A/Missouri/11/2025 (H1N1)pdm09-like virus
- A/Darwin/1454/2025 (H3N2)-like virus
- B/Tokyo/EIS13-175/2025 (B/Victoria lineage)-like virus
Cell Culture-, Recombinant Protein- or Nucleic Acid-Based Vaccines
- A/Missouri/11/2025 (H1N1)pdm09-like virus
- A/Darwin/1415/2025 (H3N2)-like virus
- B/Pennsylvania/14/2025 (B/Victoria lineage)-like virus
Zoonotic Influenza Concerns
Experts also assessed influenza viruses circulating in animals, which pose a pandemic threat. Since September 23, 2025, 25 human infections with zoonotic influenza were reported from six countries, primarily through exposure to infected animals. No human-to-human transmission was reported. A new candidate vaccine virus (CVV) for an A(H9N2) virus was recommended for development. WHO News
The Importance of Influenza Vaccination
Seasonal influenza causes an estimated 290,000 to 650,000 respiratory deaths annually, with around one billion cases globally each year. WHO News The WHO’s Global Influenza Surveillance and Response System (GISRS), established in 1952, plays a vital role in monitoring and responding to influenza outbreaks worldwide. WHO News
Related reading