1. Arud Centres for Addiction Medicine, Zurich, Switzerland
2. Center for Disease Analysis, Louisville, Colorado, USA
3. Division of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Switzerland
4. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Switzerland, and Department of Public Health, Epidemiology, Biostatistics and Prevention Institute, University of Zurich
5. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Switzerland, and Institute of Medical Virology, University of Zurich, Switzerland
6. Consultant, Denges, Switzerland
7. Swiss Hepato-pancreato-biliary Centre and Department of Gastroenterology and Hepatology, University Hospital Zurich, Switzerland
8. University Clinic of Infectious Diseases, University Hospital and University of Bern, Switzerland
9. Division of Infectious Diseases and Hospital Epidemiology, Cantonal Hospital St Gallen, Switzerland
10. Division of Gastroenterology and Hepatology, Cantonal Hospital St Gallen, Switzerland
11. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, University of Basel, Switzerland
12. Divisions of Gastroenterology and Hepatology and of Clinical Pathology, University Hospital, Geneva, Switzerland