1. Thomas J. Fitzgerald, Danielle L. Moulia, and Samuel B. Graitcer are with the Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, GA. Thomas J. Fitzgerald and Danielle L. Moulia are also with IHRC, Inc, Atlanta. Sara J. Vagi and Stephanie A. Dopson are with the Division of State and Local Readiness, Office of Public Health Preparedness and Response, CDC, Atlanta.