Residents in south-west Sydney are being warned to be on high alert following the detection of Ross River virus.
It’s been found in mosquitoes around Bankstown, with health officials telling those living in the Georges River area to be careful.
There is no treatment for the virus, which can debilitate sufferers for up to six weeks with a fever or flu-like illness and swelling of the joints.
Ground Zero is Deepwater Park at Bankstown, where trapped mosquitoes were found with the virus.
Eastern parts of Liverpool are also at risk.
Ross River virus is carried by certain female mosquitoes, which bite an infected animal and pass it on to other animals and humans.
The virus cannot be spread from one person to another.
Experts say the best way to protect yourself is to cover up, especially at dawn or dusk, and to use mosquito repellents containing diethyl toluamide, or DEET.
Residents at risk should also check their fly screens and keep babies under mosquito nets and out of biting range.
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