FLU VACCINE

• Each year, a new seasonal flu vaccine is developed based on the circulating types of flu viruses. Throughout the year, the National Centres of most countries carry out epidemiological surveillance of seasonal flu, and thedata on subtypes of the flu viruses are provided to the World Health Organization. Flu vaccines for the 2023 to 2024 season are designed to protect against the following flu viruses:

an A/Victoria/4897/2022 (H1N1) pdm09-like virus; 
an A/Darwin/9/2021 (H3N2)-like virus; a B/Austria/1359417/2021 (B/Victoria lineage)-like virus; 
a B/Phuket/3073/2013 (B/Yamagata lineage)-like virus. 

• Influenza vaccination is recommended before the start of the flu season, i.e. at the end of September-October, but vaccination is possible throughout the flu season. It takes about two weeks after flu vaccination for antibodies to develop in the body and provide protection against flu. 

• During the flu season 2023-2024, vaccination for persons belonging to risk groups is covered by the Compulsory Health Insurance. The flu vaccines comply with the recommendations of the World Health Organization for the Northern Hemisphere and the EU resolution for 2023-2024 flu season. The vaccine includes such excipients as sodium chloride, potassium chloride, disodium phosphate dihydrate, potassium dihydrogen phosphate and water for injections. 

• Seasonal flu vaccines are safe and effective, and side effects are very rare. Inactivated vaccines can cause the following side effects: local reaction at the injection site, headache, muscle pain, low-grade fever, and fatigue. The virus particles that make up the inactivated vaccine cannot cause influenza. 

Recommended composition of influenza vaccines for either northern or southern hemisphere influenza seasons

Data on number of people vaccinated with seasonal flu vaccine (updated 30/06/2023)