1. European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
2. Gastrointestinal, zoonosis and tropical diseases unit, Department of infectious diseases epidemiology, Robert Koch Institute, Berlin, Germany
3. These authors contributed equally to this article
4. National Center for Communicable Diseases Surveillance and Control, National Institute of Public Health, Bucharest, Romania
5. European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
6. Cantacuzino National Institute of Research, Bucharest, Romania
7. University of Medicine and Pharmacy ‘Carol Davila’, Bucharest, Romania
8. Department of Nephrology and Dialysis, Children’s Emergency Hospital ‘M.S. Curie’, Bucharest, Romania
9. EU Reference Laboratory for Escherichia coli, Istituto Superiore di Sanità (ISS), Rome, Italy
10. National Institute of Infectious Diseases ‘Matei Bals’, Bucharest, Romania
11. Ministry of Health, General Directorate of Medical Assistance and Public Health, Bucharest, Romania