1 Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands. c.h.vanwerkhoven@umcutrecht.nl.
2 Infection Control Program and WHO Collaborating Center, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland.
3 Division of Infectious Diseases, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland.
4 Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
5 Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands.