1. Division of Global Women’s Health, Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
2. UNC Global Projects–Zambia, Lusaka, Zambia
3. Biostatistics Core, Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
4. Department of Pathology and Microbiology, University Teaching Hospital, Lusaka, Zambia
5. Kelly Services, Rockville, Maryland, USAand
6. Department of Pediatrics and Child Health, University Teaching Hospital, Lusaka, Zambia