1. Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado 80523
2. Department of Epidemiology and Public Health, Yale University School of Medicine, 60 College Street, New Haven, Connecticut 06510
3. Department of Primary Industries and Fisheries, Brisbane, Queensland, Australia
4. Department of Microbiology, University of Colorado Health Sciences Center, Aurora, Colorado 80045
5. School of Biological Sciences, University of Northern Colorado, Greeley, Colorado 80639