1. The Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, PA
2. Tuberculosis Research Unit, Department of Epidemiology, Case Western Reserve University, Cleveland, OH
3. Division of Gastroenterology, Department of Medicine, St. Luke's-Roosevelt Hospital Center, New York, NY
4. Department of Medicine, Makerere University, Kampala, Uganda
5. Department of Ophthalmology, Johns Hopkins School of Medicine, Baltimore, MD