1 Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
2 Department of Medicine, St Michael's Hospital, Toronto, Ontario, Canada.
3 Department of Microbiology, Sinai Health System, Toronto, Ontario, Canada.
4 Department of Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
5 Public Health Ontario Laboratory, Toronto, Ontario, Canada.
6 MAP Center for Urban Health Solutions, Li Ka Shing Knowledge Institute, Toronto, Ontario, Canada.
7 Department of Epidemiology and Institute of Health Policy, Management and Evaluation, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
8 Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada.
9 Department of Medicine, Michael Garron Hospital, Toronto, Canada.