1. Dalla Lana School of Public Health University of Toronto Toronto Ontario Canada
2. ICES Toronto Ontario Canada
3. Public Health Ontario Toronto Ontario Canada
4. University Health Network Toronto Ontario Canada
5. Department of Family and Community Medicine University of Toronto Toronto Ontario Canada
6. Department of Medicine University of Toronto Toronto Ontario Canada
7. Division of Infectious Diseases Jewish General Hospital Montreal Quebec Canada
8. Center for Clinical Epidemiology Lady Davis Research InstituteJewish General Hospital Montreal Quebec Canada
9. Department of Medicine McGill University Montreal Quebec Canada
10. British Columbia Centre for Disease Control Vancouver British Columbia Canada