1. Infectious Diseases, Department of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana.
2. Lincoln Community Health Center, Durham, North Carolina.
3. Duke University Medical Center, Durham, North Carolina.
4. Durham County Department of Public Health, Durham, North Carolina.
5. Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
6. Department of Biostatistics and Bioinformatics, Duke University, Durham, North C1arolina,
7. Infectious Diseases, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.