1. Extendicare, Inc., Toronto, ON, Canada
2. Department of Microbiology, Sinai Health System, Toronto, ON, Canada
3. Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
4. Extendicare Medex Long Term Care, Ottawa, ON, Canada
5. Ottawa Public Health, Ottawa, ON, Canada
6. School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
7. Public Health Ontario, Toronto, ON, Canada
8. Department of Medicine, University of Toronto, Toronto, ON, Canada