1. Department of Medicine University of Ottawa Ottawa Ontario Canada
2. Clinical Epidemiology Program Ottawa Hospital Research Institute Ottawa Ontario Canada
3. School of Epidemiology and Public Health University of Ottawa Ottawa Ontario Canada
4. Department of Medicine (Geriatrics), Faculty of Medicine Dalhousie University Halifax Nova Scotia Canada
5. Canadian Center for Vaccinology (CCfV), IWK Health Center, Nova Scotia Health Halifax Nova Scotia Canada
6. Department of Medicine (Infectious Diseases), Faculty of Medicine Dalhousie University Halifax Nova Scotia Canada
7. Department of Pathology, Faculty of Medicine Dalhousie University Halifax Nova Scotia Canada