1. Institute of HIV/AIDS Prevention and Control; Guangxi Center for Disease Control and Prevention; Nanning 530028 China
2. Department of Infectious Diseases; Beijing 302 Hospital; Beijing 100069 China
3. AIDS Antiviral Treatment Clinic; Guangxi Center for Disease Control and Prevention; Nanning 530028 China
4. AIDS Research Center; Ruikang Hospital affiliated to Guangxi University of Chinese Medicine; Nanning 530011 China
5. National Center for AIDS/STD Control and Prevention; Chinese Center for Disease Control and Prevention; Beijing 102206 China