1. Biosecurity Laboratory (LSE), Animal Health National Service (SENASA), Heredia, Costa Rica
2. Virology Laboratory, Veterinary Medicine School, Tropical Disease Research Program, Universidad Nacional (UNA), Heredia, Costa Rica
3. Pathology Laboratory, LSE, Animal Health National Service (SENASA), Heredia, Costa Rica
4. Department of Biomedical Sciences, Section of Anatomic Pathology, Cornell University, Ithaca, New York, USA
5. Diagnostic Department, Animal Health National Service (SENASA), Heredia, Costa Rica