About the Authors

Yong Zhang

Affiliation Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China

Lin Lu

Affiliation Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China

Lei Ba

Affiliation Aaron Diamond AIDS Research Center, Rockefeller University, New York, New York, United States of America

Li Liu

Affiliations 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

Li Yang

Affiliation Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China

Manhong Jia

Affiliation Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China

Haibo Wang

Affiliation State Key Laboratory of Virology, Modern Virology Research Center and AIDS Center, Wuhan University, Wuhan, Hubei, People's Republic of China

Qing Fang

Affiliation Aaron Diamond AIDS Research Center, Rockefeller University, New York, New York, United States of America

Yuhua Shi

Affiliation Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China

Wenyun Yan

Affiliation Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China

Guangcai Chang

Affiliation Yunnan Center for Disease Control and Prevention, Kunming, Yunnan, People's Republic of China

Linqi Zhang

Affiliations 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

David D Ho

Affiliation Aaron Diamond AIDS Research Center, Rockefeller University, New York, New York, United States of America

Zhiwei Chen

To whom correspondence should be addressed. E-mail: zchen@adarc.org

Affiliations 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

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

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.