A major health warning has been issued after three people were hospitalised with Legionnaires’ disease in NSW.

Three people living in Potts Point, in central Sydney, have recently developed the disease.

The people, aged in their 40s to 70s, are not known to each other.

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Legionnaires’ disease is contracted by exposure to Legionella bacteria, and outbreaks can occur when bacteria from environmental sources such as cooling towers atop large buildings become contaminated.

The disease is not spread from person to person.

“People can be exposed to the bacteria if contaminated water particles from a cooling system are emitted into the air and breathed in,” South Eastern Sydney Local Health District Public Health Unit Director Vicky Sheppeard said.

“Legionnaires’ disease can develop up to 10 days after exposure,” Dr Sheppeard said.

“Symptoms include fever, chills, a cough and shortness of breath and may lead to severe chest infections such as pneumonia.

“People who develop this disease are diagnosed by a urine or sputum test and chest X-ray and usually require antibiotic treatment in hospital.

“Those most at risk are elderly people, people with underlying lung or other serious health conditions, and people who smoke.”

NSW Health and City of Sydney have inspected and sampled all cooling towers within 500 metres of the infected residents’ homes, and have requested that all cooling water systems in the broad investigation area be disinfected.

“Building owners should ensure that their cooling towers are operated and maintained in compliance with the NSW Public Health Regulation 2022,” NSW Health said.

NSW Health urged anyone experiencing symptoms of illness to seek medical advice.