1. European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
2. National Centre of Epidemiology, CIBERESP, Carlos III Health Institute, Madrid, Spain
3. Public Health Agency of Sweden, Stockholm, Sweden
4. National Institute of Public Health Romania-National Centre for Communicable Diseases Surveillance and Control, Bucharest, Romania
5. Sciensano, Brussels, Belgium
6. Department of Infectious Diseases Epidemiology, National Institute of Public Health, Prague, Czechia
7. National Influenza Reference Laboratory, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
8. Center for Virology, Medical University Vienna, Vienna, Austria
9. Infectious Disease prevention and Control unit, Malta
10. National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
11. Health Service Executive-Health Protection Surveillance Centre, Dublin, Ireland
12. WHO Regional Office for Europe, Copenhagen, Denmark