Australia has confirmed its first H5N1 bird flu case in a mammal after authorities found the virus in a long-nosed fur seal in South Australia.
The seal was found dead near Beachport, about 310 kilometres south of Adelaide. Authorities said the animal showed no signs of injury.
The discovery marks a new stage in Australia’s growing bird flu outbreak. The highly pathogenic virus has spread among wild birds since it reached the country in June.
H5N1 Found in Dead Fur Seal
South Australian authorities confirmed the H5N1 detection in the long-nosed fur seal.
The animal was among an estimated population of 100,000 seals living in the state’s waters.
Officials said the seal had no visible injuries when it was found. They also said its death did not appear to be linked to other sick or dead marine mammals.
The finding has raised concerns about the virus spreading further through Australia’s wildlife.
Bird Flu Outbreak Expands Across Australia
Australia has reported a growing number of H5N1 cases since the virus arrived in June.
The outbreak initially affected migratory seabirds. It later spread to native bird species.
Australia also recorded its first mass seabird deaths from H5N1 this month. The development marked a significant escalation in the outbreak.
Federal authorities said 297 cases have been confirmed nationwide.
However, the virus has not yet been detected in Australia’s poultry or agricultural sector.
Minister Warns of Wildlife Losses
Federal Agriculture Minister Julie Collins said the spread of H5N1 in the natural environment could cause major wildlife losses.
She said authorities cannot completely prevent losses once the virus spreads through wild populations.
The government is monitoring the situation closely. Officials are also watching for signs of further transmission among marine mammals.
Australia Was the Last Continent to Report Bird Flu
Australia was the last continent to report bird flu.
The virus had already reached Australia’s sub-Antarctic territory of Heard Island in late 2025.
The outbreak there had a devastating impact on young seals. Local media reported that more than 13,000 seal pups died after the virus spread on the island.
The latest case in South Australia shows that H5N1 now poses a wider threat to Australian wildlife.
No H5N1 Detected in Australian Poultry
Despite the spread among wild animals, Australian authorities have not detected H5N1 in the country’s poultry or agricultural industries.
That remains an important distinction for the farming sector.
Authorities continue to monitor domestic animals and wildlife for new infections. They are also tracking the movement of the virus among wild bird populations.
H5N1 Raises New Wildlife Concerns
The first mammal detection adds another concern to Australia’s bird flu response.
H5N1 can infect different animal species. Its spread among wild birds can also create opportunities for transmission to mammals.
The discovery of the infected seal does not mean the virus has entered Australia’s agricultural sector. However, it highlights the changing nature of the country’s outbreak.
Authorities will continue monitoring wildlife as they assess the potential impact of H5N1.
