About the Author: Nkuchia M. M'ikanatha, Division of Infectious Disease Epidemiology, Pennsylvania Department of Health, Harrisburg, PA, USA Ruth Lynfield, Minnesota Department of Health, St Paul, MN, USA Chris A. Van Beneden, Respiratory Diseases Branch, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA Henriette de Valk, Infectious Disease Department, Institut de Veille Sanitaire, Saint Maurice, France