José Ernesto Ramirez-Gonzalez, Elizabeth Gonzalez-Duran, Patricia Alcantara-Perez, Claudia Wong-Arambula, Hiram Olivera-Diaz, Iliana Cortez-Ortiz, Gisela Barrera-Badillo, Ha Nguyen, Larisa Gubareva, Irma Lopez-Martinez, Jose Alberto Díaz-Quiñonez, Miguel Angel Lezana-Fernández, Hugo Lopez Gatell-Ramírez, Jose Angel Cordova Villalobos, Mauricio Hernández-Avila, and Celia Alpuche-Aranda 

Author affiliations: Author affiliations: Instituto de Diagnóstico y Referencia Epidemiológicos, Mexico City, Mexico (J.E. Ramirez-Gonzalez, E. Gonzalez-Duran, P. Alcantara-Perez, C. Wong-Arambula, H. Olivera-Diaz, I. Cortez-Ortiz, G. Barrera-Badillo, I. Lopez-Martinez, J.A. Díaz-Quiñonez, M.A. Lezana-Fernández, H.L. Gatell-Ramírez, J.A.; Cordova Villalobos, M. Hernández-Avila, C. Alpuche-Aranda); Secretaría de Salud, Mexico City (J.E. Ramirez-Gonzalez, E. Gonzalez-Duran, P. Alcantara-Perez, C. Wong-Arambula, H. Olivera-Diaz, I. Cortez-Ortiz, G. Barrera-Badillo, I. Lopez-Martinez, J.A. Díaz-Quiñonez, M.A. Lezana-Fernández, H.L. Gatell-Ramírez, J.A. Cordova Villalobos, M. Hernández-Avila, C. Alpuche-Aranda); Centers for Disease Control and Prevention, Atlanta, Georgia, USA (H. Nguyen, L. Gubareva)