Health Unit declares Legionnaires' disease outbreak in Orillia over

NEWS -

The Simcoe Muskoka District Health Unit (SMDHU) has declared an outbreak of Legionnaires' disease in Orillia over.

"We are confident that with the testing, monitoring and completion of any required cleaning and disinfection of the cooling towers that continue to operate in Orillia at this time, there is no further risk of transmission associated with this outbreak. As such, the health unit is declaring the conclusion of this outbreak," said Dr. Charles Gardner, SMDHU medical officer of health, in a press release.

The outbreak has been traced back to the Orillia Rotary Place cooling tower, where the health unit says a strain of Legionella was a genetic match with one of the 35 cases.

Of the 35 infected individuals, one person has died.

The city says testing for the bacteria has been done every few days since the cooling tower resumed operations following the repair of the heat exchanger at the end of October.

While tests done on Nov. 1 and 4 showed no detection of Legionella bacteria, testing on Nov. 7 showed low bacteria levels within the cooling tower.

Although the city says the levels are not high enough to be an active risk to the community, it's decided to shut down the cooling tower until a root cause can be determined.

This means the two ice surfaces at the West Orillia Sports Complex are also now closed.

"The health and safety of our community are absolutely paramount. The most recent testing identified low levels of Legionella, and keeping the cooling tower at Rotary Place operational is not a risk that we are willing to take," said Mayor Steve Clarke. "We need to get to the root of what is causing this, and the facts are we don't know."

"The City has done everything we can operationally at this time. There are no legislated standards regarding the operation of cooling towers. The city will continue to rely on the advice and recommendations of industry experts, including a specialized engineering firm, to analyze the system for a plan of action moving forward."

As part of its investigation, ten cooling towers were tested at 17 sites in Orillia, with the other seven shut down for the season before testing could be complete.

Legionella bacteria is commonly found in natural freshwater environments but can become a health concern in water systems such as cooling towers, according to the SMDHU.

It adds that people can contract the disease when they inhale aerosolized water droplets containing the bacteria.