1. Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
2. Epidemiology Resource Center, Indiana State Department of Health, Indianapolis, Indiana, USA
3. Department of Pathology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
4. Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, USA
5. Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
6. American Red Cross Scientific Affairs, Gaithersburg, Maryland, USA
7. Division of Public Health, Wisconsin Department of Health Services, Madison, Wisconsin, USA
8. Department of Pathology and Laboratory Medicine, University of Wisconsin Hospital and Clinics, Madison, Wisconsin and American Red Cross Blood Services, Madison, Wisconsin, USA