1. Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
2. Epidemic Intelligence Service, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
3. Colorado Department of Public Health and Environment, Denver, Colorado, USA
4. Emory University School of Medicine, Atlanta, Georgia, USA
5. Atlanta VA Medical Center, Atlanta, Georgia, USA
6. Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
7. Oregon Health Authority, Portland, Oregon, USA
8. Vanderbilt University School of Medicine, Nashville, Tennessee, USA
9. California Emerging Infections Program, Oakland, California, USA
10. New Mexico Department of Health, Santa Fe, New Mexico, USA
11. Minnesota Department of Health, St. Paul, Minnesota, USA