1. Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, the Netherlands
2. Department of Internal Medicine & Infectious Diseases, University of Groningen, University Medical Center Groningen, the Netherlands
3. National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
4. National Reception Center for Asylum Seekers (Gezondheidscentrum Asielzoekers), Ter Apel, the Netherlands