Were You in Sydney CBD This Month? Health Officials Warn of Legionnaires’ Disease Risk

Were You in Sydney CBD This Month? Health Officials Warn of Legionnaires’ Disease Risk

Updated: 30 December 2025 · Sydney

Health authorities have issued a renewed warning for Sydney’s central business district after a fourth case of potentially deadly Legionnaires’ disease was confirmed, prompting concerns about a growing cluster linked to one of the city’s busiest commercial areas.

All four people diagnosed with the illness — including three cases confirmed earlier this week — spent time in Clarence Street near Wynyard between 9 December and 18 December, according to NSW Health. The patients are not believed to be connected to one another outside of their presence in the area and are all currently receiving treatment in hospital.

Legionnaires’ disease is caused by Legionella bacteria, which can grow in warm water systems and spread through fine droplets in the air. The bacteria most commonly enter the environment through cooling towers on large buildings, air-conditioning systems and other industrial water sources.

“People are exposed if contaminated water particles from a cooling system are in the air and then breathed in,” said Dr Vicky Sheppeard, director of the communicable diseases branch at NSW Health.

“Symptoms can develop up to 10 days after exposure and include fever, chills, a cough and shortness of breath, and may lead to severe chest infections such as pneumonia.”

Those considered most at risk include older people, smokers, and individuals with underlying lung conditions or serious chronic illnesses. Health officials have stressed that the disease does not spread from person to person, but early diagnosis is critical, as untreated cases can become severe.

NSW Health has advised anyone who spent time in the Clarence Street or Wynyard areas during the exposure window to monitor for symptoms for up to 10 days and to seek medical advice promptly if they become unwell.

Investigations into the source of the outbreak are continuing. NSW Health has confirmed that building managers across the CBD are being urged to inspect and service their cooling towers as a precaution while environmental testing is carried out.

Legionnaires’ disease outbreaks are uncommon but tend to occur in dense urban environments where large cooling systems are in use. Even after a source is identified and cleaned, additional cases can emerge due to the disease’s incubation period, which can range from two to 10 days.

Further updates are expected as investigations progress. Official health advice and outbreak updates are available via NSW Health, along with a detailed overview of symptoms and prevention measures here.

You may also like: More breaking health and safety updates on Swikblog

Written by Swikblog Desk · About Us

Add Swikblog as a preferred source on Google

Make Swikblog your go-to source on Google for reliable updates, smart insights, and daily trends.