1. Institute of Medical Virology, Hospital of Johann Wolfgang Goethe University, D-60596 Frankfurt am Main, Germany
2. Bernhard Nocht Institute for Tropical Medicine, Diagnostic Virology Laboratory, D-20359 Hamburg, Germany
3. Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute for Novel and Emerging Infectious Diseases, D-17493 Greifswald, Germany