About the Authors
Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China
Aaron Diamond AIDS Research Center, Rockefeller University, New York, New York, United States of America
State Key Laboratory of Virology, Modern Virology Research Center and AIDS Center, Wuhan University, Wuhan, Hubei, People's Republic of China
The authors have declared that no competing interests exist.
Z. Chen designed the study. L. Zhang, D. Ho, and Z. Chen analyzed the data. Z. Chen wrote the paper with contributions from Y. Zhang, L. Zhang, and D. Ho. Y. Zhang, L. Lu, L. Yang, M. Jia, Y. Shi, W. Yan, and G. Chang did sample collection, ELISA, Western Blot, viral RNA extraction, PCR, and data collection as well as taking part in discussions. L. Ba, L. Liu, H. Wang, Q. Fang, and Z. Chen did RT-PCR, PCR product purification, and sequencing reactions. Y. Zhang, L. Lu, and M. Jia collected and analyzed surveillance data from 80 sentinel sites and 16 prefectures. D. Ho and Z. Chen provided overall project coordination.