1. Department of Viroscience, WHO Collaborating Centre for Arbovirus and Haemorrhagic Fever Reference and Research, Erasmus MC, Rotterdam, the Netherlands
2. Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
3. Institute for Tropical Diseases, Harbour Hospital, Rotterdam, the Netherlands
4. General practice Havelte, Havelte, the Netherlands
5. Laboratory for Medical Microbiology and Infectious diseases, Isala Clinics, Zwolle, the Netherlands
6. German Centre for Infection Research (DZIF), Hamburg-Luebeck-Borstel, Hamburg, Germany
7. Bernhard Nocht Institute for Tropical Medicine, WHO Collaborating Centre for Arbovirus and Haemorrhagic Fever Reference and Research, Hamburg, Germany