1. Division of Infectious Diseases and Hospital Epidemiology University Hospital Zurich Zurich Switzerland
2. Institute of Medical Virology University of Zurich Zurich Switzerland
3. Service of Immunology and Allergy Lausanne University Hospital University of Lausanne Lausanne Switzerland
4. Department of Biomedicine University of Basel Basel Switzerland
5. Laboratory of Virology Geneva University Hospital Geneva Switzerland
6. Division of Infectious Diseases and Hospital Epidemiology University Hospital Basel Basel Switzerland
7. Clinical Virology, Laboratory Medicine University Hospital Basel Basel Switzerland
8. Department of Infectious Diseases Bern University Hospital Bern Switzerland
9. Institute for Infectious Diseases University of Bern Bern Switzerland
10. Division of Infectious Diseases Cantonal Hospital St Gallen St Gallen Switzerland
11. Service of Infectious Diseases Lausanne University Hospital University of Lausanne Lausanne Switzerland
12. Division of Infectious Diseases Regional Hospital Lugano Lugano Switzerland