1. School of Public Health, Department of Epidemiology University of Michigan Ann Arbor Michigan USA
2. Sustainable Sciences Institute Managua Nicaragua
3. Centro de Salud Sócrates Flores Vivas Ministry of Health Managua Nicaragua
4. School of Public Health, Department of Population Health Sciences Georgia State University Atlanta Georgia USA
5. Laboratorio Nacional de Virología, Centro Nacional de Diagnóstico y Referencia Ministry of Health Managua Nicaragua
6. College of Veterinary Medicine, Center for Vaccines and Immunology University of Georgia Athens Georgia USA
7. College of Veterinary Medicine, Department of Infectious Diseases University of Georgia Athens Georgia USA