The deadly H5N1 strain of bird flu has now been found in a second state, South Australia, after earlier being identified in Western Australia.

Authorities have confirmed three seabirds have died of the highly pathogenic avian influenza (HPAI) H5N1 virus. It is too early to know if H5N1 has spread beyond these animals to other wildlife or livestock in Australia. But it appears very much a matter of when, not if, this happens.

Globally, H5N1 has already devastated wildlife populations. In Australia, this deadly virus could greatly disrupt ecosystems and push our most threatened species even closer to extinction.

Why is H5N1 so dangerous?

The H5N1 strain of bird flu spreads through contact with bodily fluids such as saliva and faeces, infected animals or contaminated environments. It can also be transmitted through scavenging by species that feed on infected carcasses.

Since 2021, the H5N1 strain has killed millions of the world’s wild birds, mammals and poultry. This is because it can spread faster than other HPAI strains – including between mammals – and move between continents via migratory birds.

However, it’s hard to predict how H5N1 will affect our wildlife and ecosystems. This strain of the virus is not yet established in Australia. And many of our species are endemic – meaning they’re not found anywhere outside Australia – so we don’t have the data needed to reliably predict how H5N1 may affect them.

Read more: The first case of H5N1 bird flu in Australia has been........

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