[1] Univ Cambridge, Dept Zool, Cambridge CB2 3EJ, England
[2] Ctr Dis Control & Prevent CDC, WHO, Collaborating Ctr Influenza, Atlanta, GA 30333 USA
[3] NIH, Fogarty Int Ctr, Bethesda, MD 20892 USA
[4] Erasmus MC, Dept Virol, NL-3000 CA Rotterdam, Netherlands
[5] InDRE Prolongac Carpio, Mexico City 11340, DF, Mexico
[6] USN, Hlth Res Ctr, San Diego, CA 92152 USA
[7] Arizona State Publ Hlth Lab, Phoenix, AZ 85007 USA
[8] Colorado Dept Publ Hlth & Environm, Denver, CO 80230 USA
[9] Indiana State Dept Hlth Labs, Indianapolis, IN 46202 USA
[10] Minnesota Dept Hlth, Publ Hlth Lab, St Paul, MN 55164 USA
[11] Nebraska Publ Hlth Lab, Omaha, NE 68198 USA
[12] Westchester Cty Dept Labs & Res Publ Hlth Labs, Valhalla, NY 10595 USA
[13] New York State Dept Hlth, Wadsworth Ctr, Slingerlands, NY USA
[14] Ohio Dept Hlth Lab, Reynoldsburg, OH USA
[15] S Carolina Dept Hlth & Environm Control, Columbia, SC 29223 USA
[16] Dallas Cty Hlth & Human Serv, Dallas, TX 75207 USA
[17] San Antonio Metro Hlth Dist, Brooks City Base, TX 78235 USA
[18] Texas Childrens Hosp, Diagnost Virol Lab, Houston, TX 77030 USA
[19] San Diego Publ Hlth Lab, San Diego, CA 92186 USA
[20] Imperial Cty Publ Hlth Dept, El Centro, CA 92243 USA
[21] CDC, Border Infect Dis Surveillance Project, Atlanta, GA 30333 USA
[22] Massachusetts Dept Publ Hlth, William A Hinton State Lab Inst, Jamaica Plain, MA 02130 USA
[23] Calif Dept Publ Hlth, Viral & Rickettsial Dis Lab, Richmond, CA 94804 USA
[24] Marshfield Clin Fdn Med Res & Educ, Marshfield, WI 54449 USA
[25] Michigan Dept Community Hlth, Lansing, MI 48906 USA
[26] NYU, Dept Hlth & Mental Hyg, Publ Hlth Lab, New York, NY 10016 USA