1. Department of Epidemiology and Biostatistics, School of Public Health Tianjin Medical University Tianjin China
2. HIV/Hepatitis/STI/TB, World Health Organization Representative Office in China Beijing China
3. Shenlan Public Health Counseling Service Center Tianjin China
4. STD & AIDS Control and Prevention Section, Tianjin Center for Disease Control and Prevention Tianjin China
5. Tianjin Key Laboratory of Pathogenic Microbiology of Infectious Disease, Tianjin Center for Disease Control and Prevention Tianjin China