Avian influenza has been detected at an egg farm in Victoria, marking the first time the virus has been found in Australia in four years.
The discovery comes amid growing concerns of a global outbreak.
Authorities are currently investigating a number of poultry deaths in Meredith, south of Ballarat.
Agriculture Victoria confirmed preliminary tests showed the presence of bird flu and are now testing to determine if it is the highly pathogenic H5N1 strain that has spread to every other continent, including Antarctica.
Victoria's chief veterinary officer Dr Graeme Cooke said: "Agriculture Victoria is responding with staff on the ground supporting the business with further laboratory investigations as necessary."
He urged poultry farmers, backyard flock owners, and bird enthusiasts to report any cases of unexplained bird deaths.
Australia is currently declared free of all high pathogenicity (HPAI) strains of avian influenza. The disease was last detected in 2020, also at an egg farm south of Ballarat, leading to tens of thousands of farmed birds being euthanised.
The current global outbreak has killed millions of birds and thousands of mammals, devastating commercial bird populations.
It has also spread to humans, with one case reported in Texas involving a man who had been in contact with dairy cows.
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