1. Escuela de Medicina Veterinaria, Universidad Nacional de Costa Rica; Heredia, Costa Rica
2. Programa de Sanidad Acuícola; Servicio Nacional de Salud Animal, Ministerio de Agricultura y Ganaderia; Heredia, Costa Rica
3. Laboratorio de Patologia Aviar; Escuela de Medicina Veterinaria, Universidad Nacional; Heredia Costa Rica
4. Department of Pathology, College of Veterinary Medicine; University of Georgia; Athens Georgia
5. Department of Pathobiology and Population Medicine, College of Veterinary Medicine; Mississippi State University; Stoneville Mississippi
6. Department of Epidemiology and Medicine; Davis-School of Veterinary Medicine, University of California; Davis California
7. Programa de Investigación en Enfermedades Tropicales; Escuela de Medicina Veterinaria, Universidad Nacional; Heredia Costa Rica