People in Melbourne are being urged to stay alert for Legionnaires’ disease after health authorities recorded a significant increase in cases since Friday.
Twenty-two cases have been confirmed, a majority of which required hospitalisation and some needing intensive care for severe community acquired pneumonia.
The Victorian Department of Health said a further six people were suspected to have the disease.
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All cases are people who visited or live in metropolitan Melbourne.
Authorities are still trying to determine the source of the outbreak through testing of local cooling towers and other potential sources
Legionnaires’ disease is a severe form of pneumonia that can cause a chest infection.
It is caused by bacteria found in bodies of water or potting mix.
The disease’s symptoms include fever, chills, cough, headache and muscle aches and pain.
People over 40 are at higher risk, especially those who are immune compromised, or who smoke.
“People who live in, work in or have visited metropolitan Melbourne and surrounding areas, and develop symptoms of Legionnaires’ disease, should seek urgent medical care,” the department said.
“If Legionnaires’ disease is suspected, request urgent urinary antigen testing through your normal pathology provider.”