1. D. Finzi, M. Hermankova, T. Pierson, L. M. Carruth, C. Buck, R. E. Chaisson, T. C. Quinn, J. Gallant, R. F. Siliciano, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
2. K. Chadwick and J. Margolick, Department of Molecular Microbiology and Immunology, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD 21205, USA.
3. R. Brookmeyer, Department of Biostatistics, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD 21205, USA.
4. M. Markowitz and D. D. Ho, Aaron Diamond AIDS Research Center, 455 First Avenue, New York, NY 10016, USA.
5. D. D. Richman, Departments of Medicine and Pathology, University of California San Diego, La Jolla CA 92093, USA.