The flu virus keeps changing(1). This is why the flu vaccine needs to be modified each year to target the flu viruses expected to be circulating in the coming season(1). But who decides the composition of each year’s influenza vaccine?
The World Health Organization (WHO), the United Nations specialized agency responsible for international public health, convenes an advisory group of experts twice a year – in February and in September – to analyse global influenza surveillance data and make influenza vaccine recommendations for the upcoming flu season(2). Influenza vaccines recommendations for use in the Northern Hemisphere are given in February, and influenza vaccines recommendations for use in the Southern Hemisphere are given in September(2).
Who are part of this advisory group of experts?
The WHO vaccine composition advisory group is made up of representatives from each WHO Collaborating Centres for influenza of the Global Influenza Surveillance and Response System (GISRS), as well as representatives from the WHO Essential Regulatory Laboratories, National Influenza Centres, representatives from the WHO Collaborating Centre for Modelling, Evolution, and Control of Emerging Infectious Diseases and experts on animal influenza(3). The advisory group of experts makes each influenza vaccine composition recommendation based on an analysis of the global influenza activity and the results of vaccine antibody studies(4).
What happens after the WHO announces its recommendations?
In the European Union (EU), the European Medicines Agency (EMA)’s ad hoc Influenza Working Group makes the final decision and issues influenza vaccine composition recommendations for the upcoming EU flu season(5). The vaccine manufacturers in the EU then follow EMA’s recommendations and produce the flu vaccines to be released in autumn(5), before the flu season arrives in the Northern Hemisphere which is generally between November and April of each year(1).
While getting the flu vaccine is the most effective way to protect yourself from influenza(6), it is important to also take other precautions to protect yourself against the flu. During this flu season, make sure you are practicing good hand hygiene, staying healthy by eating wholesome meals and exercising, and avoiding close contact with sick people(7).
(1) Factsheet about seasonal influenza. ECDC. Available at: https://www.ecdc.europa.eu/en/seasonal-influenza/facts/factsheet. Accessed on: 15 August 2022
(2) Recommended composition of influenza virus vaccines for use in the 2022 southern hemisphere influenza season. WHO. Available at: https://cdn.who.int/…/202109_recommendation.pdf?sfvrsn=698a54b9_12&download=true. Accessed on: 15 August 2022
(3) Recommendations announced for influenza vaccine composition for the 2022-2023 northern hemisphere influenza season. WHO. Available at: https://www.who.int/news/item/25-02-2022-recommendations-announced-for-influenza-vaccine-composition-for-the-2022-2023-northern-hemisphere-influenza-season. Accessed on: 15 August 2022
(4) WHO consultation on the composition of influenza virus vaccines for use in the 2022-23 northern hemisphere influenza season. WHO. Available at: https://www.who.int/…/who-consultation-on-the-composition-of-influenza-virus-vaccines-for-use-in-the-2022-23-northern-hemisphere-influenza-season. Accessed on: 15 August 2022
(5) EU recommendations for 2022-2023 seasonal flu vaccine composition. European Medicines Agency. Available at:https://www.ema.europa.eu/en/news/eu-recommendations-2022-2023-seasonal-flu-vaccine-composition. Accessed on: 15 August 2022
(6) Seasonal influenza vaccines. ECDC. Available at: https://www.ecdc.europa.eu/en/seasonal-influenza/prevention-and-control/seasonal-influenza-vaccines. Accessed on: 15 August 2022
(7) Protect yourself against flu: Learn more about preventive measures. ECDC. Available at: https://www.ecdc.europa.eu/en/seasonal-influenza/prevention-and-control/personal-protective-measures. Accessed on: 15 August 2022