5 days ago
Cooling tanks at LHSC Victoria test positive for legionella bacteria, which causes legionnaires disease
London Health Sciences Centre says the cooling towers at Victoria Hospital have tested positive for the legionella bacteria.
They can grow in hot tubs and hot water tanks, or large plumbing or air conditioning systems, places where water turns to vapour.
Now the London Health Sciences Centre (LHSC) says legionella bacteria, the bacteria that cause legionnaires disease, have been found in samples from the cooling towers at the Victoria campus.
'Water evaporates and becomes aerosolized, where the bacteria can be in the air, then inhaled by people, and people can get sick,' explained Dr. Nadim Khalil, the Site Lead, Infection, Prevention and Control at LHSC Children's Hospital.
So what is legionnaires disease?
LHSC describes it as a serious type of pneumonia, though it is not spread by person-to-person contact.
Signs can include fever, chills, dry cough, and shortness of breath.
On July 9, Middlesex London Health Unit declared a legionnaires outbreak within a six-kilometre radius in southeast London. As of Tuesday, there were 69 reported cases, and two deaths.
london - legionnaires - july 2025
A heat map provided by the Middlesex-London Health Unit shows the general area of confirmed cases (home addresses) of Legionnaires' disease reported to the Middlesex-London Health Unit in 2025.
'Even though there have been 69 cases, it's still fairly low number just considering the population of London. That falls down to roughly one in 10,000 people getting sick,' said Dr. Khalil.
While LHSC Victoria falls within the catchment area, officials say the hospital is not the source of the outbreak.
'There's not an increased risk from catching legionella from being in the hospital than anywhere else in London,' said Dr. Khalil. 'So unfortunately, just because we do fall in that radius,' he explained.
Dr. Khalil said LHSC is doubling its efforts with chemical cleaning of the cooling tanks.
'So regardless of the test results, we have had treatment done to the water supply, and we are proceeding with an even more aggressive treatment and cleaning, just to make sure we're not causing any potential harm to the community,' he said.
The hospital is awaiting results of the positive samples, taken about a week ago. That's to determine whether it's the same strain found in the community. They're expected in about three weeks.