1. Center for Infectious Diseases, Beijing You’an Hospital, Capital Medical University, Beijing, People’s Republic of China
2. Aaron Diamond AIDS Research Center, Columbia University, New York, NY, USA
3. Institute of HIV/AIDS, The First Hospital of Changsha, Changsha, People’s Republic of China
4. School of Public Health, Fudan University, Shanghai, People’s Republic of China
5. Guangzhou Center for Disease Control and Prevention, Guangzhou, People’s Republic of China
6. Shanghai CSW & MSM Center, Shanghai, People’s Republic of China
7. Key Laboratory of AIDS Immunology of National Health Commission of the People’s Republic of China, Department of Laboratory Medicine, The First Affiliated Hospital of China Medical University, Shenyang, People’s Republic of China