1. Division of Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina.
2. University of North Carolina Project-Malawi, Lilongwe, Malawi.
3. Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina.
4. Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina.
5. London School of Hygiene and Tropical Medicine, London, United Kingdom.
6. Department of Obstetrics and Gynecology, University of Chicago, Chicago, Illinois.
7. Department of Biology, University of North Carolina, Chapel Hill, North Carolina.
8. Department of Geography, University of North Carolina, Chapel Hill, North Carolina.