1. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
2. Institute of Medical Virology, University of Zurich, Zurich, Switzerland
3. Institute of Nursing Science, University of Basel, Basel, Switzerland
4. Department of Infectious Diseases, Bern University Hospital, University of Bern, Bern, Switzerland
5. Department of Infectious Diseases and Hospital Hygiene, Cantonal Hospital Aarau, Aarau, Switzerland
6. Center for Infectious Diseases Zurich, Zurich, Switzerland
7. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, University of Basel, Basel, Switzerland
8. Division of Infectious Diseases, Cantonal Hospital St Gallen, St Gallen, Switzerland
9. Primary Care Medicine Division, University Hospital Geneva, Geneva, Switzerland
10. Intensive Care Unit, Department of Intensive Care Medicine, University of Lausanne and University Hospital Center, Lausanne, Switzerland
11. Division of Infectious Diseases, Regional Hospital Lugano, Lugano, Switzerland
12. Department Public and Global Health, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland