1. Research Group of HIV Molecular Epidemiology and Virology, The State Key Laboratory of Virology, Wuhan Institution of Virology, Chinese Academy of Sciences, Wuhan, Hubei, The People's Republic of China.
2. Guangxi Province Center for Disease Prevention and Control, Nanning, Guangxi, The People's Republic of China.
3. Department of AIDS Research, The State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, The People's Republic of China.