B.Sc., McGill University, Montreal, Quebec, Canada, 1985.
M.D.C.M., McGill University, Montreal, Quebec, Canada, 1989.

Residency/Fellowship: Baylor College of Medicine, Houston, Texas (internal medicine), 1989-1991; (chief resident), 1991-1992; Yale University School of Medicine, New Haven, Conn. (postdoctoral research, infectious diseases), 1992-1993; (fellowship, infectious diseases) 1993-1996; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Conn. (postdoctoral fellowship), 1994-1997.

Yale University School of Medicine, New Haven, Conn., instructor, Internal Medicine, 1997-1999; associate research scientist and lecturer, Department of Epidemiology and Public Health, 2000-2001; Assistant Clinical Professor, 2001-2005; Yale University Health Services, New Haven, Conn., chief, clinical resources, Department of Laboratory Medicine, 2000-2001; medical director, 2001-2005; University of New Mexico School of Medicine, Albuquerque, N.M., Associate Professor of Internal Medicine, 2005-2010; Professor, Medicine and Infectious Diseases, 2011-2017; director, Program in Global and Geographic Medicine, 2005-2010; vice chair, Department of Internal Medicine, 2005-2014; director, Center for Global Health, 2010-2017; Albuquerque VA Medical Center, New Mexico VA Health Care System, Albuquerque, N.M., Chair of Medicine, 2005-2014; Stritch School of Medicine, Loyola University Medical Center, Chicago, Ill., chair, Department of Medicine, 2017-2020; Professor, Department of Public Health Sciences, 2017-2020; John W. Clark Endowed Professor of Medicine, 2017-2020.

Appointed to the staff of Mayo Clinic in Florida, 2020; chair, Division of Infectious Diseases, 2020-present; Professor of Medicine, Mayo Clinic College of Medicine and Science, 2023-present.