1. Veterinary Laboratories Agency–Shrewsbury, Shrewsbury, UK
2. Veterinary Laboratories Agency–Starcross, Exeter, UK
3. Wrexham Veterinary Care, Wrexham, UK
4. Diagnostic Center for Population and Animal Health, Michigan State University, Lansing, Michigan, US
5. Abbey Veterinary Services, Newton Abbot, UK
6. Virus Surveillance Unit, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, UK