1. Institute of Materials, École Polytechnique Fédérale de Lausanne, Station 12, 1015 Lausanne, Switzerland
2. Institute of Microbiology, University Hospital of Lausanne and University of Lausanne, Rue du Bugnon 48, 1011 Lausanne, Switerland
3. Faculty of Veterinary Medicine Department of Pathology, University of Liège, Sart Tilman B43a, 4000 Liège, Belgium
4. Institute of Experimental Immunology, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
5. Department of Infectious Diseases and Hospital Hygiene, University Hospital Zurich, University of Zurich Rämistrasse 100, 8091 Zurich, Switzerland