1. Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa;
2. Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland;
3. Harvard T.H. Chan School of Public Health, Boston, Massachusetts;
4. Frontier Science Foundation, Brookline Massachusetts;
5. Social and Scientific Systems, a DLH Company, Silver Spring, Maryland;
6. TASK Applied Science and Stellenbosch University, Cape Town, South Africa;
7. Division of AIDS, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland;
8. Frontier Science Foundation, Amherst, New York; and
9. Department of Internal Medicine, University of Nebraska Medical Center, Omaha, Nebraska