1. Department of Medicine, School of Medicine, University of California San Francisco, San Francisco, California.
2. UNC-Project China, Guangzhou, China.
3. Center for Medical Anthropology and Behavioral Health, School of Anthropology and Sociology, Sun Yat-sen University, Guangzhou, China.
4. Guangzhou Eighth People's Hospital, Guangzhou, China.
5. Institute of Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.