1. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Switzerland
2. Department of Primary Care and Population Sciences, University College London, United Kingdom
3. Central Laboratory of Virology, Division of Infectious Diseases, Geneva University Hospitals and Faculty of Medicine, University of Geneva
4. National Center for Retroviruses, University of Zurich
5. Division of Immunology and Allergy, Lausanne University Hospital
6. Institute for Medical Microbiology, University of Basel
7. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel
8. Division of Infectious Diseases, Regional Hospital Lugano
9. University Hospital, University of Lausanne
10. Division of Infectious Diseases, University Hospital Berne and University of Berne
11. Division of Infectious Diseases, Geneva University Hospital
12. Division of Infectious Diseases, Cantonal Hospital St Gallen, Switzerland