1. Department of Emergency Medicine, Massachusetts General Hospital, Harvard Medical School, Boston
2. Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
3. Departments of Pediatrics and Medicine, University of Wisconsin School of Medicine and Public Health, Madison
4. Department of Molecular Virology and Microbiology and Pediatrics, Baylor College of Medicine, Houston, Texas
5. Division of Allergy and Immunology, Phoenix Children's Hospital, Phoenix, Arizona
6. Division of Emergency Medicine and Department of Pediatrics, Children’s National Health System, Washington, DC
7. Division of Hospital Medicine, Children's Hospital of Los Angeles, Los Angeles, California