Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
Correspondence: Aron J. Hall, DVM, MSPH Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd NE, Mailstop A-34, Atlanta, GA 30333 ([email protected]).
Received January 13, 2012
Accepted January 13, 2012
