1. Vanderbilt Institute for Global Health, Vanderbilt University, Nashville, Tennessee.
2. State Key Laboratory for Infectious Disease Prevention and Control and National Center for AIDS/STD Control and Prevention (NCAIDS), Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
3. Department of Pediatrics, Vanderbilt University, Nashville, Tennessee.
4. Department of Medicine, Vanderbilt University, Nashville, Tennessee.
5. Department of Biostatistics, Vanderbilt University, Nashville, Tennessee.