1. Medical Intensive Care Unit, Department of Internal Medicine, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland
2. Service of Infectious Diseases, Department of Internal Medicine, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland
3. Laboratory of Molecular Biology, Department of Internal Medicine, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland
4. Department of Fundamental Microbiology, University of Lausanne, 1015 Lausanne, Switzerland
5. Division of Infectious Diseases, University Hospital of Geneva,1211 Geneva 14, Switzerland
6. Institute of Medical Microbiology, University Hospital of Münster, 48149 Münster, Germany
7. Institute of Medical Microbiology and Hygiene, University of the Saarland, 66421 Homburg, Germany