1. Institute of Medical Microbiology, Jena University Hospital, Friedrich Schiller University, 07747 Jena, Germany
2. Division Nosocomial Pathogens and Antibiotic Resistance, Department of Infectious Diseases, Robert Koch Institute, 38855 Wernigerode, Germany
3. Department of Hospital Hygiene, Sophien-und Hufeland-Klinikum, 99425 Weimar, Germany