1. Department of Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands;
2. Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands;
3. Department of Public Health and Primary Care, Leiden University Medical Center, Leiden, The Netherlands;
4. Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands;
5. Centre for Infectious Disease Control, Dutch National Institute for Public Health and the Environment, Bilthoven, The Netherlands