1. Infectious Diseases Unit; Bolzano Central Hospital; Bolzano Italy
2. Infection Control Program; University of Geneva Hospitals and Faculty of Medicine; Geneva Switzerland
3. Division of Infectious Diseases; University of Geneva Hospitals and Faculty of Medicine; Geneva Switzerland
4. Department of General Internal Medicine, Rehabilitation and Geriatrics; University of Geneva Hospitals and Faculty of Medicine; Geneva Switzerland
5. World Health Organization Collaborating Centre on Patient Safety; University of Geneva Hospitals and Faculty of Medicine; Geneva Switzerland