Communicable disease surveillance reports for Toronto are no longer available online in PDF format. Please contact the Communicable Disease Surveillance Unit by phone 416-392-7411 or email during business hours Monday to Friday, 8:30 a.m. to 4:30 p.m. to request data or information related to communicable diseases in Toronto. We apologize for any inconvenience.

A summary of reportable communicable disease data for the City of Toronto for 2017 (the most recent calendar year for which data are available) is posted on the page: Communicable Diseases in Toronto. For each disease, a comparison to the previous five-year period is included.

Detailed summaries of reportable disease by gender and age groups for 2017 are available on Open Data.

Additional data and information on communicable disease trends and activities in Ontario and Toronto can be accessed via Public Health Ontario, including:

Current reportable disease trends in Toronto are summarized in this report. To allow adequate time for reports to be processed, and for investigations and quality assurance checks to be completed, data are posted with a delay of approximately two months. Updated data are published monthly around the middle of the month, and can be accessed via the City’s Open Data portal. An additional resource is Public Health Ontario’s monthly report, linked below.

This is the final Toronto Public Health weekly influenza bulletin for the 2018/19 season. Production and distribution of the weekly influenza bulletins for the 2019/20 influenza season will begin in Fall 2019, once increased influenza activity in Toronto is detected.

The full report is distributed each Friday, by email subscription. 

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Technical notes to accompany the Weekly Influenza News

Summary of Influenza Activity in Toronto: Week 20 (May 12 to May 18, 2019)

 Indicator Activity Level*  Description
Laboratory-Confirmed Influenza Cases Higher In week 20‡, 39 new laboratory-confirmed cases of influenza were reported, higher than the 25 cases reported in week 19. To date this season, 2,621 cases have been reported, lower than the previous 5-season mean of 3,175 cases.
Influenza Strains for Ontario Cases§ No report As of week 18, the Ontario Respiratory Pathogen Bulletin reported 851 isolates for Ontario cases to date this season:

  • A/Michigan/45/2015, H1N1 (n=674),
  • A/Singapore/INFIMH-16-0019/2016-like (n=131),
  • B/Colorado/06/2017-like (n=29),
  • B/Phuket/3073/13-like (n=17).
Influenza Outbreaks in Toronto Healthcare Institutions Lower No institutional influenza outbreak was reported in week 20.
Overall Comparable Influenza activity in Toronto for week 20 was comparable to week 19.

*May not reflect statistically significant changes, but describes overall observed trends and compares to the previous surveillance week.

Starting in the 2017/18 season, the Ontario Ministry of Health and Long-Term Care advised public health units that they were no longer required to do any additional investigation to collect information beyond what has already been reported in the initial laboratory report. No changes were made to investigations of institutional influenza outbreaks. As a result, subtype information will be available for a smaller proportion of laboratory-confirmed cases, and hospitalization and death information will be underestimated. Therefore, comparisons between the current season and prior seasons should be made with caution. Please refer to the technical notes for details.

Due to a lag in entry of influenza cases in the 2018/19 season, the number of cases with reported dates in the current week may be an underestimate and will increase as more cases are entered in coming weeks.

§Data on influenza strains for Ontario cases are obtained from the Ontario Respiratory Pathogen Bulletin published the week preceding the current Weekly Influenza News for Toronto (e.g. for the Weekly Influenza News for week 34, the influenza strains data are obtained from the Ontario Respiratory Pathogen Bulletin published for week 33).

Additional Data and Information for Ontario and Nationally