Australia confirmed its first mainland case of the deadly H5N1 bird flu in a seabird in Western Australia, with the detection made near Esperance. The H5N1 virus has now been found on every continent; before these detections, Australia was the only continent without a confirmed mainland case.

A brown skua tested positive for avian influenza in Western Australia, and a giant petrel also tested positive (or was a suspected positive) for H5N1 in the same region.

Accounts differ on the status of the case: some sources report a confirmed case of H5N1 in a seabird in Western Australia, while other reports describe it as a suspected case involving a brown skua.

According to 7news.com.au, Australia detected its first suspected mainland case of H5N1 bird flu in a brown skua in Western Australia. The GDELT agency reported that Australian officials said there is no evidence of spread of the virus to local poultry or resident bird populations. The Guardian noted that poultry farms in Western Australia were placed under lockdown after the virus was confirmed on the mainland. Hindustan Times reported that New South Wales became the third Australian state to confirm an H5N1 bird flu case and that six infections have been confirmed across three Australian states. Dawn reported that the H5 strain was confirmed on Heard Island in late 2025. Al Jazeera reported that Australia pledged action on H5N1 after the bird flu case was confirmed.