1. Beijing Red Cross Blood Center; Beijing China
2. Division of HIV and Sexual Transmitted Virus Vaccine; National Institutes for Food and Drug Control; Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech Products; Beijing China
3. College of Life Science; Jilin University; Changchun China
4. Department of Microbiology and Infectious Disease Center; School of Basic Medical Sciences; Peking University Health Science Center; Beijing China
5. Institute of Blood Transfusion; Chinese Academy of Medical Sciences; Chengdu China
6. Division of Blood Transfusion; HIV Specialty Testing Laboratory; Department of Pathology; Johns Hopkins Medical Institutions; Baltimore Maryland
7. Department of Epidemiology; Johns Hopkins Bloomberg School of Public Health; Baltimore Maryland