1. Clinic for Ruminants; Department for Farm Animals and Herd Management; University of Veterinary Medicine; Veterinärplatz 1 A-1210 Vienna Austria
2. Austrian Agency for Health and Food Safety; Institute for Veterinary Disease Control; Robert Kochgasse 17 A-2340 Mödling Austria
3. Clinical Virology; Clinical Department for Diagnostic Imaging, Infectious Diseases and Clinical Pathology; University of Veterinary Medicine; Veterinärplatz 1 A-1210 Vienna Austria
4. Institute for Applied Statistics and System Analysis; Joanneum Research; Steyrergasse 25a A-8010 Graz Austria