1. 1 The National Veterinary Institute & The Swedish University of Agricultural Sciences Joint R&D Division, Departments of Virology Ulls väg 2B SE-751 89 Uppsala Sweden
2. 2 Central Agricultural Office Veterinary Diagnostic Directorate Budapest Hungary
3. 3 Technical University of Denmark National Veterinary Institute Lindholm, Kalvehave Denmark
4. 4 Szent István University Department of Microbiology and Infectious Diseases, Faculty of Veterinary Science Budapest Hungary
5. 5 Institute for Veterinary Medicinal Products Department of Virology Budapest Hungary
6. 6 Swedish University of Agricultural Sciences Department of Biomedical Sciences and Veterinary Public Health Uppsala Sweden