1. Public Health and Epidemiology research group, School of Medicine and Health Sciences, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
2. National Centre of Epidemiology, Carlos III National Health Institute (ISCIII), Madrid, Spain
3. Epiconcept, Paris, France
4. Vaccine Preventable Diseases and Immunisation, European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
5. Sciensano, Elsene, Belgium
6. Department of Infectious Disease Epidemiology and Prevention, Statens Serum Institut (SSI), Copenhagen, Denmark
7. Infectious Diseases Department, Istituto Superiore di Sanità, Rome, Italy
8. Ministry of Health, Directorate of Health, Service epidemiology and statistics, Luxembourg
9. CIBER Epidemiología y Salud Pública (CIBERESP), Spain
10. Instituto de Salud Pública de Navarra – IdiSNA, Pamplona, Spain
11. Center for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
12. Norwegian Institute of Public Health (NIPH), Oslo, Norway
13. Departamento de Epidemiologia, Instituto Nacional de Saúde Doutor Ricardo Jorge, Departamento de Epidemiologia, Lisboa, Portugal
14. CIBER on Infectious Diseases (CIBERINFEC), Madrid, Spain