1. Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
2. Department of Monitoring and Evaluation, Public Health Agency of Sweden, Solna, Sweden
3. Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
4. Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
5. Department of Infectious Disease Surveillance and Control, National Institute for Health and Welfare, Helsinki, Finland
6. Department of Food, Water and Cosmetics, Norwegian Institute of Public Health, Oslo, Norway
7. European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control, Stockholm, Sweden
8. Department of Hygiene and Epidemiology, University of Thessaly, Thessaly, Greece
9. Norwich Medical School, University of East Anglia, Norwich, United Kingdom
10. Gastrointestinal, Emerging and Zoonotic Diseases Department, Public Health England, London, United Kingdom
11. European Centre for Disease Prevention and Control, Stockholm, Sweden