Latest news with #DrNadimKhalil
CTV News
5 days ago
- Health
- CTV News
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.
CBC
5 days ago
- Health
- CBC
Legionella bacteria found at London's Victoria hospital, officials say
Social Sharing Testing of Victoria Hospital's cooling towers has returned positive results for legionella bacteria as local health officials investigate an ongoing Legionnaires' disease outbreak in the city, according to officials at London Health Sciences Centre (LHSC). LHSC officials say two samples were taken from the hospital's cooling towers and air-conditioning systems on July 16 and 17. It followed confirmation from the Middlesex-London Health Unit (MLHU) that the Victoria campus fell within a six-kilometre radius where most cases in the outbreak had been found. In a statement on Wednesday, southwestern Ontario's largest hospital network revealed that the cooling tower samples came back positive for legionella bacteria on an initial screening test. "More testing is now underway to find out if it matches the strain causing the community outbreak," the statement said. "Those results will take approximately three weeks. We want to be clear: this does not mean Victoria Hospital is the source of the community outbreak." LHSC said the risk to patients, staff and visitors remains very low, but individuals who are older, have lung problems or are immunocompromised (have a weak immune system) are at greater risk of serious infection. The outbreak, declared on July 8, has impacted at least 69 people, according to the latest numbers from the MLHU. Two people have since died, and source of the outbreak has not yet been determined. In an interview, Dr, Nadim Khalil, site lead of infection prevention and control at Children's Hospital, said no hospital-acquired cases had presented to LHSC. "The public health unit has been testing different samples to see what could be the source of it, and because of our location at Victoria Hospital, we got tested. We have sent samples from our University Hospital as well, which is going to be much more lower-risk," he said. He added that cooling towers are, "more to help evaporate some of the temperature that's in the building, but not circulate into the air conditioning system." Legionnaires' disease is caused by legionella bacteria, naturally found in water sources like hot tubs, cooling towers, hot water tanks, large plumbing systems or parts of air-conditioning systems. Legionella is not transmitted from person to person. If the bacteria are aerosolized or misted into the air (via wind or fans), people may inhale the bacteria and become unwell. Most people exposed to legionella don't get ill, but some may experience Pontiac fever, a mild, flu-like illness that commonly resolves itself. "The challenging thing for us is the cooling towers have to be present to help cool the building, especially during summer, (but) the waters can be a bit stagnant in it because it's not circulating with the rest of the building," Khalil said. "We do have our policies to get the water tested per provincial guidelines as well as treatment. We treat the water twice a year. When we did hear about the outbreak, we treated the water an extra time." Khalil says LHSC treated the water a fourth time to be safe, but says the results came back positive, prompting a chemical cleaning of the towers, followed by a thorough systematic clean. One challenge, he says, is that legionella can be slow to develop — upwards of two weeks on an agar plate. "So they do additional DNA amplification, what we call PCR, to help see if there's any residual bacteria, and that's what came back positive. What that means is still unclear," he said. "We do know a lot of water, if it's going to be tested, can be positive, and we do know, talking to the health unit, almost 80 per cent of samples they've had have tested positive."
