“This is, at the moment, a single bird with suspected H5 bird flu. It is not yet confirmed whether it is the strain that is circulating and I will reiterate that it is not in the poultry system or the agricultural system,” she said.
“We certainly expected we could not be H5 free forever as the only continent free of the H5 bird flu. We know it has impacted other countries and continents across the globe and we did say at the time we could not stop it arriving in Australia.”
The strain previously killed thousands of seals and penguins on sub-Antarctic Australian islands. Photo / Getty Images
Collins said the infected bird is now dead but initial testing on it had returned a positive result.
The minister said the positive result was being verified, with confirmation expected within the next 24 hours.
A second unwell bird, found near the first, is also set to undergo testing.
“We expect the results to come in overnight or early tomorrow,” she said.
“We have always said we could not keep it out forever, so it is about making sure we are prepared as we can be.”
The news comes a day after scientists confirmed they believe the strain has killed 13,000 elephant seal pups and hundreds of king penguins on the sub-Antarctic Australian islands of Heard and McDonald.
A sick migratory bird in southern Western Australia has tested positive for H5 bird flu. Photo / Getty Images
“We have only had one test confirmed in an isolated area of southern Western Australia,” Collins said.
“We will have the facts by tomorrow of what strain this is.”
After the announcements, experts have called for caution, urging authorities to carry out rapid diagnostics and the public to avoid unnecessary animal contact.
Dr Carol Booth, of the Invasive Species Council, said the potential detection was “deeply concerning”.
“We desperately hope this is not the realisation of our worst dreams,” she said.
“The recent reported mass deaths of elephant seals on Heard Island were a harbinger of potential catastrophe for Australian wildlife if the virus has made it to mainland Australia.
Experts are verifying if the dead bird had the same H5 strain that killed 13,000 seal pups. Photo / Getty Images
“If H5N1 is confirmed, the Government’s own risk assessment predicts potentially catastrophic impacts on native birds, while the virus’ increasing ability to infect mammals raises the prospect of severe impacts on marine mammals and other wildlife.
“It is a good thing governments have spent the past two years preparing for the arrival of bird flu, but a mainland detection would be a critical test of Australia’s preparedness and response systems.
“Even if this is a false alarm, it warns against any complacency.”
Dr Matthew Mason, a public health expert at the University of Sunshine Coast, said the risk to humans was low.
“The suspected detection of H5 avian flu in Western Australia is a significant development that warrants calm, evidence-informed public communication,” he said.
“The likelihood of human infection is low, and there is limited evidence of human-to-human transmission with the current strain.
University of Queensland’s Professor Paul Griffin said the suspect case warranted “close attention”.
“For most Australians, the most important thing they can do right now is ensure they are up to date with their annual influenza vaccination as we head into the influenza season.
“If you find sick or injured birds, be sure to avoid making contact with them and report them to the relevant authorities to assist with ongoing surveillance.
“While the situation deserves careful monitoring, there is no reason for alarm based on the information we currently have.”
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