1. U.S. Department of Agriculture, Agricultural Research Service, National Animal Disease Center, Ruminant Diseases and Immunology Research Unit, Ames, Iowa, USA
2. Institute for Medical Microbiology, Virology, and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
3. German Center for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel, Hamburg, Germany
4. Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Research Group Virus Genomics, Hamburg, Germany
5. Institute of Virology, University of Veterinary Medicine, Hannover, Germany
6. German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Hannover, Germany