1. Department of Infectious Diseases, Georgetown University Medical Center, Washington, District of Columbia.
2. Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
3. David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California.
4. Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.
5. Bloomberg School of Public Health, John Hopkins University, Baltimore, Maryland.
6. Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.