1. School of Medicine, Emory University, Atlanta, Georgia;
2. Advisory Committee on Immunization Practices, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA;
3. Department of Pediatrics, Warren Alpert Medical School of Brown University, Providence, Rhode Island;
4. Division of Infectious Diseases, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, Illinois; and
5. Virginia H. Rogers Professor of Pediatric Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, Illinois