Millions of people who visited Sydney's CBD over Christmas and New Year are being urged to stay alert for symptoms of Legionnaires' disease after seven people were diagnosed with the debilitating lung disease.
NSW Health issued a health alert on Wednesday for anyone who has visited the city center since Christmas Eve or in the past ten days, to monitor for symptoms such as cough, fever, shortness of breath and headache.
It comes after three women and four men, aged between 20 and 70, were admitted to hospital with pneumonia before being diagnosed as carriers of the Legionella bacteria, which causes Legionnaires' disease.
The people are believed to have visited locations in Sydney's CBD between Bathurst St, Sussex St, Elizabeth St and Circular Quay, all locations visited over the holiday period, in the 10 days prior to their symptoms.
Millions of people who have been in the CBD since Christmas Eve have been urged to check for Legionnaires' disease after seven people were diagnosed with the disease (stock image)
NSW Health said symptoms of Legionnaires' disease can develop up to 10 days after exposure to contaminated water particles in the air and can lead to serious respiratory infections such as pneumonia.
The disease cannot be transmitted from person to person. Instead, it is usually spread by contaminated water particles emitted from a cooling system. Smokers and people with underlying health and lung problems are at greatest risk.
NSW Health said environmental health officers were working closely with the City of Sydney Council to inspect cooling towers and a review of maintenance records could help identify which more towers need to be inspected.
'Managers of buildings with cooling towers are approached and informed about the cluster. Building owners must ensure that their cooling towers are operated and maintained in accordance with regulations,” they said.
More than a million people flocked to the city center on New Year's Eve alone to watch the world-famous fireworks displays (pictured)
'Public health units in local health districts in NSW are monitoring cases of Legionnaires' disease and working closely with local councils in the management of cooling towers.
“Routine monthly testing of cooling towers allows for the early identification of contaminated towers and allows for rapid additional cleaning and corrective action.”
A variant of Legionnaires' disease can also be spread through soil and potting soil. In September, NSW Health said as many as 52 people had been exposed to the disease as a result of inhaling the bacteria from the soil.