1 Department of Medicine (Dinh, Kanji, Vaughan), Cumming School of Medicine, University of Calgary and Alberta Health Services; Provincial Public Health Laboratory (Kanji), Alberta Health Services; Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases (Vaughan), University of Calgary and Alberta Health Services, Calgary, Alta.
2 Department of Medicine (Dinh, Kanji, Vaughan), Cumming School of Medicine, University of Calgary and Alberta Health Services; Provincial Public Health Laboratory (Kanji), Alberta Health Services; Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases (Vaughan), University of Calgary and Alberta Health Services, Calgary, Alta. stephen.vaughan@albertahealthservices.ca.