¹The working group was established by request of the World Health Organization’s Global Influenza Programme, Department of Epidemic and Pandemic Alert and Response (WHO, GIP, EPR), the World Organisation for Animal Health (OIE), and the Food and Agriculture Organization (FAO). It consisted of the following members: Ruben O. Donis, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA (co-chair); Gavin J.D. Smith, University of Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China (co-chair); Michael L. Perdue, WHO, GIP, EPR, Geneva, Switzerland² (coordinator); Ian H. Brown, Veterinary Laboratories Agency, Addlestone, UK; Hualan Chen, Harbin Veterinary Research Institute, Chinese Academy of Agriculture Sciences CAAS, Harbin, People’s Republic of China; Ron A.M. Fouchier, Erasmus University, Rotterdam, the Netherlands; Yoshihiro Kawaoka, University of Wisconsin-Madison, Madison, Wisconsin, USA, and Institute of Medical Science, University of Tokyo, Tokyo, Japan; John Mackenzie, Curtin University of Technology, Perth, Western Australia, Australia; and Yuelong Shu, China Centers for Disease Control, Bejing, People’s Republic of China. In addition, the following persons made substantial contributions: Ilaria Capua, Instituto Zooprofilattico Sperimentale delle Venezie, Padova, Italy; Nancy Cox, Todd Davis, Rebecca Garten, and Catherine Smith, CDC; Yi Guan and Dhanasekaran Vijaykrishna, University of Hong Kong; Elizabeth Mumford, WHO, GIP, EPR; and Colin A. Russell and Derek Smith, University of Cambridge, Cambridge, UK.

²Current affiliation: US Department of Health and Human Services, Washington, DC, USA.