1. Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia
2. Texas A&M University Health Science Center College of Medicine, Temple
3. Baylor Scott & White Health Research Institute, Temple, Texas
4. Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
5. Department of Pediatric Emergency Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
6. Kaiser Permanente Washington Health Research Institute, Seattle, Washington
7. Center for Clinical Epidemiology & Population Health, Marshfield Clinic Research Institute, Marshfield, Wisconsin
8. Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor