1. Institute of Virology and Immunology, Bern and Mittelhäusern, Switzerland
2. Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
3. Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
4. Spiez Laboratory, Spiez, Switzerland
5. Division of Veterinary Anatomy, Department of Clinical Research, Vetsuisse Faculty, University of Bern, Bern, Switzerland
6. Institute for Experimental Virology, Twincore Centre for Experimental and Clinical Infection Research, Hannover, Germany
7. Department of Molecular and Medical Virology, Ruhr-University Bochum, Bochum, Germany