print header


UPDATED Nov. 8, 2022 - The health unit has concluded its investigation into a Legionnaires’ disease outbreak in Orillia, first announced Oct.7.

After an extensive investigation of 27 known cooling towers at 17 sites in Orillia, it was determined that a strain of Legionella found in the Orillia Rotary Place cooling tower was a genetic match with one sputum sample of a case of Legionnaires’ disease among the total cluster of 35 cases. Testing for the source of the other 34 cases could not be done. In addition, testing could not be done for seven of the sites as they had been shut down for the season before the investigation.

Testing for Legionella bacteria has been completed every few days since the Rotary Place cooling tower resumed operations following the repair of the heat exchanger at the end of October. The tests completed on Nov. 1 and 4 provided no detection of Legionella bacteria; however, testing on Nov. 7 showed the presence of Legionella. While the levels were not high enough to be an active risk to the community at this time, the City of Orillia determined that the safest option was to shut down the cooling tower until a root cause can be determined.

With the testing, monitoring and completion of any required cleaning and disinfection of the cooling towers that continue to operate in Orillia, including the shutdown of the Rotary Place cooling tower, the health unit has determined that at this time there is no further risk of transmission associated with this outbreak. As such, the health unit has declared the conclusion of this outbreak.

The bacteria can cause Legionnaires’ disease, medically known as Legionellosis. Legionnaires' disease can cause a variety of symptoms. Some of the most common are fever, chills, cough and difficulty breathing. Other symptoms can also develop, such as headaches, muscle pain and digestive problems (e.g., loss of appetite, nausea, vomiting or diarrhea).  People generally develop symptoms two to 10 days following exposure to the bacteria.

The bacteria responsible for the disease, Legionella, is commonly found in natural freshwater environments. However, it can become a health concern in water systems, such as cooling towers, plumbing systems in large buildings and certain medical devices when conditions allow the bacteria to multiply.

People can develop Legionnaires’ disease when they inhale aerosolized water droplets containing the bacteria. People cannot get Legionnaires’ disease by drinking water and it cannot be passed from person to person. Most people exposed to the bacteria do not become ill.

People over the age of 50, individuals who smoke, or those with certain medical conditions, including weakened immune systems, chronic lung disease or other chronic health conditions, are at increased risk for Legionnaires’ disease. There are oral antibiotics that can be used to treat pneumonia caused by legionella.

We recommend that anyone with persistent fever and difficulty breathing to follow up with their health care provider, call Health Connect Ontario (formerly known as Telehealth) at 811 (TTY: 1-866-797-0007) or seek medical attention.

Visit our webpages for more information about Legionella and Legionellosis (Legionnaires’ disease), or call Health Connection at 705-721-7520 or 1-877-721-7520, Monday-Friday, 8:30 a.m. to 4:30 p.m.


Did you find what you were looking for today?
What did you like about this page?
How can we improve this page?

If you have any questions or concerns that require a response, please contact Health Connection directly.

Thanks for your feedback.
Failed to submit comment. Please try submitting again or contact us at the Health Unit.
Comment already submitted ...