1. Division of Infectious Diseases, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada
2. Correspondence: Dara Petel, Division of Infectious Diseases, Department of Paediatrics, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, Canada, M5G 1X8. Telephone: (416) 713-3086..
3. Infection Prevention & Control, The Hospital for Sick Children, Toronto, Ontario, Canada
4. Public Health Ontario, Toronto, Ontario, Canada
5. Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
6. Department of Family Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
7. Division of Microbiology, The Hospital for Sick Children, Toronto, Ontario, Canada
8. Department of Laboratory Medicine & Pathobiology, The Hospital for Sick Children, Toronto, Ontario, Canada
9. Department of Paediatrics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
10. Division of Paediatric Medicine, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada