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