Sydney Legionnaires’ outbreak claims one life

An outbreak of Legionnaires’ disease in Sydney’s CBD has resulted in tragedy, with one person losing their life and a further 11 infected. All those infected spent time in the Sydney CBD and adjacent suburbs between March 13 and April 5, 2025.

In a statement, Health NSW says a possible source of the outbreak has been identified.

“Legionella bacteria have been found in one cooling tower and further testing is underway to determine if it is the source of the outbreak. The tower is being decontaminated,” the statement reads.

“All current confirmed cases were exposed in late March or early April and people who were in the Sydney CBD and surrounds during this time are asked to be aware for symptoms of Legionnaires’ disease, including fever, chills, a cough and shortness of breath.”

Dr Vicky Sheppeard from the South Eastern Sydney Local Heath District points out that Legionnaires’ disease can only spread directly from environmental source such as cooling towers, not from person to person.

“NSW Health continues to work closely with the City of Sydney to identify, inspect and sample any cooling towers in the CBD potentially implicated in the outbreak,” Sheppeard says. “To date, over 165 cooling towers have been inspected and tested.”

Timely update for DA17

AIRAH is in the process of updating DA17, the Institute’s design application manual for cooling towers. The manual covers wet type evaporative cooling towers, wet and dry closed-circuit towers (hybrid, dry, adiabatic pre-cooled), and alternative methods of heat rejection (air-cooled, natural heat sinks).

The update to DA17  will include:

• Development of a set of industry-derived energy protocols for evaporative cooling towers
• Updating to reflect the latest developments in industry, including changes to regulations, risk assessment, tower technology and system management via the cloud
• Updating to reflect any changes to AS/NZS 3666 standards
• Updating the resources on improving energy and water efficiency in existing cooling towers.

The manual is aimed at system manufacturers, designers, installers and maintenance providers, as well as system owners and managers, operators and users.

AIRAH members can access all of the Institute’s design application manuals online.