1. Department of Viroscience, Erasmus University Medical Centre, Rotterdam, The Netherlands
2. College of Marine Science, University of South Florida, Saint Petersburg
3. Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
4. Department of Medical Microbiology, Leiden University Medical Centre, Bilthoven, The Netherlands
5. Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, The Netherlands