- Case Counts: Public Health Ontario. Query: Case counts of reportable diseases by public health unit and year. Toronto, ON: Ontario Agency for Health Protection and Promotion; extracted on January 16, 2025.
- Population estimates: Statistics Canada 2014-2022, IntelliHEALTH Ontario, Ministry of Health, extracted on April 23, 2024.
- Population projections: Statistics Canada, 2023, IntelliHEALTH Ontario, Ministry of Health, extracted on April 23, 2024.
Legionella
Legionellosis is caused by a group of bacteria called Legionella species that are found in natural and man-made environments such as cooling towers, potable water systems, lakes, rivers, and streams. It can also be found in soil. Legionella can become a health concern when it grows in these water systems and devices, and is inhaled in the form of droplets and mists released into the air.
Local Information
2024 Statistics
Incidence rate is the number of new cases of disease divided by the number of persons at risk for the disease during a particular time period.
Cases:
4*
Incidence rate per 100,000 in 2024: 2.9
*Includes confirmed cases in 2024.
Incidence rate per 100,000 of Legionellosis by year

More Information about Legionellosis
Should one go to childcare, school, or work if they have Legionellosis?
Contact our Communicable Disease Control (CDC) program at 705-474-1400 or toll free at 1-800-563-2808, ext. 5229, or by email to cdc@healthunit.ca for more information.
Last updated: February 2025, by CDC