1. National Center for Emerging Zoonotic and Infectious Diseases, Centers for Disease Control and Prevention (CDC), Athens, Georgia
2. National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Athens, Georgia
3. College of Medicine, Florida State University, Tallahassee, Florida
4. College of Veterinary Medicine, University of Georgia, Athens, Georgia
5. Office of Epidemiology and Research, Puerto Rico Department of Health, San Juan, Puerto Rico