1. Department of Veterans Affairs, Edward Hines Jr Veterans Affairs Hospital, Illinois
2. Gastroenterology Division, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
3. Infectious Diseases, Sheba Medical Center, Tel Hashomer, and Sackler School of Medicine, Tel-Aviv University, Israel
4. Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver
5. McMaster University, Hamilton, Ontario, Canada
6. Division of Infectious Diseases, Washington University School of Medicine, St Louis, Missouri
7. Division of Infectious Diseases and Travel Medicine, Georgetown University School of Medicine, Washington, D.C
8. Division of Digestive Diseases, University of Cincinnati, Ohio
9. Department of Medicine, Division of Gastroenterology, University of Alberta, Edmonton, Canada
10. Clinical Research, Infectious Diseases, Kenilworth, New Jersey
11. Late Development Statistics, Biostatistics, Kenilworth, New Jersey
12. Global Scientific and Medical Publications, Infectious Diseases, Merck & Co, Inc, Kenilworth, New Jersey