1. Departamento de Patología, Escuela de Medicina Veterinaria, Universidad Nacional, Heredia, Costa Rica
2. Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
3. University of Helsinki, Faculty of Veterinary Medicine, Department of Veterinary Biosciences, Helsinki, Finland
4. University of Helsinki, Faculty of Medicine, Medicum, Department of Virology, Helsinki, Finland