1. Section of Infectious Diseases, Boston Medical Center, Boston, Massachusetts
2. Now with London School of Hygiene and Tropical Medicine, London, United Kingdom
3. Yale School of Public Health, New Haven, Connecticut
4. Department of Population Health Sciences, Weill Cornell Medical College, New York, New York
5. Boston University School of Public Health, Boston, Massachusetts
6. Section of General Internal Medicine and Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora
7. Department of Medicine, Section of General Internal Medicine, Boston Medical Center, Boston, Massachusetts
8. Department of Biostatistics, Brown University School of Public Health, Brown University, Providence, Rhode Island
9. Section of Infectious Diseases, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts