1. From the Division of Gastroenterology and Hepatology (T.G.S., R.T.C., A.T.C.) and the Clinical and Translational Epidemiology Unit (T.G.S., A.T.C.), Department of Medicine, Massachusetts General Hospital, Harvard Medical School (T.G.S., R.T.C., A.T.C.), Broad Institute (R.T.C., A.T.C.), and the Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health (A.T.C.) — all in Boston; the Department of Infectious Diseases, School of Medical Sciences, Faculty of Medicine and...