1. Municipal Health Service, (GGD Rotterdam e.o.) Rotterdam, the Netherlands
2. Department of Dermatology and Venereology, Erasmus Medisch Centrum, Rotterdam, The Netherlands
3. Department of Medical Microbiology and Infectious Diseases, Erasmus Medisch Centrum, Rotterdam, The Netherlands
4. Erasmus Medical Centre, (Erasmus Medisch Centrum), Rotterdam, the Netherlands
5. Erasmus Medisch Centrum Rotterdam, Rotterdam
6. Department of Gastroenterology and Hepatology, Erasmus Medisch Centrum, Rotterdam, The Netherlands