1. Department of Virology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
2. Department of Veterinary Biosciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
3. Animal Health and Welfare Department, Finnish Food Authority, Helsinki, Finland
4. Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
5. Department of Geosciences and Geography, Faculty of Science, University of Helsinki, Helsinki, Finland