Victoria announces statewide poultry lockdown as bird flu cases soar

Large poultry producers will be forced to house their birds due to a government order. (Supplied: Sunny Queen)

Victorian poultry producers will be forced to house their birds, as cases of H5N1 bird flu continue to climb   

The announcement builds on a voluntary housing order in place, and farms with more than 50 birds will now be forced to house their birds.

Agriculture Minister Michaela Settle said the government hoped the measure would prevent the spread of the disease.

"This is a proactive, precautionary measure to protect our industry," she said.

"This is about making sure that [farm animals] are not having that contact with wildlife."

It comes after poultry producer Ingham's locked down its WA operations in June after the deadly H5 variant of bird flu was discovered in a migratory bird near Esperance.

No cases of H5N1 bird flu have been detected in the Australian poultry industry yet. (ABC News: Tegan Osborne)

In an update on Friday, Australian Chief Veterinary Officer Beth Cookson said testing had now confirmed a further 20 positive detections in Victoria, all in greater crested terns from the Portland and Nelson area.

"There have now been 175 confirmed or presumed positive detections of H5 bird flu in Australia, based on samples tested," Dr Cookson said.

"There remain no detections in poultry or in our agricultural production system."

She said the threat to humans remained very low.

Concerns are also rising in other states, with the Royal Adelaide Show announcing it will cancel its bird and poultry exhibits at next month's event due to rising bird flu case numbers.

With concerns for bird safety growing, the Australian Consumer and Competition Commission (ACCC) is now allowing farmers to keep chickens indoors and still use free-range cartons.