Legionella bacteria found at London's Victoria hospital, officials say

Victoria Hospital's cooling towers have tested positive for legionella bacteria at the time of an ongoing legionnaires' outbreak in the city, according to officials at London Health Sciences Centre (LHSC).

On July 17 and 18, two samples were taken from the hospital's cooling towers and air-conditioning systems after the Middlesex-London Health Unit (MLHU) confirmed the Victoria campus was within the six-kilometre radius where most cases of legionnaires disease were found.

"Yesterday, we learned that Victoria Hospital's cooling towers tested positive for legionella bacteria on an initial screening test," southwestern Ontario's largest hospital network said in a news release on Wednesday.

"More testing is now underway to find out if it matches the strain causing the community outbreak. 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."

Earlier this month, health officials declared a legionnaires outbreak in London, which has left two people dead and dozens more ill so far. MLHU has been working to identify the source of the outbreak.

Legionnaires' disease is caused by legionella bacteria, naturally found in water sources such as 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.

LHSC said the risk to patients, staff and visitors remains very low, and it's taking cautionary steps to protect everyone's health and safety.

"As soon as we learned of the positive result, we initiated a chemical cleaning of the cooling towers. A systematic terminal clean will follow," LHSC said.

Individuals who are older, have lung problems or are immunocompromised (have a weak immune system) are at greater risk of serious infection.

More to come.