25 Nov 2025: Testing has confirmed the presence of H5 high pathogenicity avian influenza (H5 bird flu) in samples collected from southern elephant seals on Heard Island, a sub-Antarctic Australian external territory. Samples were collected after Australian Antarctic Program scientists observed unusual levels of mortality in elephant seals during a recent management voyage to Heard Island. Australia’s H5 bird flu freedom status remains unchanged, but the test results serve as a reminder of the importance of ongoing vigilance, coordinated biosecurity measures, and preparedness across governments, industry, and conservation partners. More information is available on the Australian Department of Agriculture, Fisheries and Forestry website.
H5 bird flu is also known as high pathogenicity avian influenza H5N1. It includes the serious and highly contagious H5N1 clade 2.3.4.4b strain which has has been spreading globally since 2021 through the movement of wild birds, with unprecedented impact. H5 bird flu can also affect other animals, and millions of wild animals worldwide have died due to the virus.
Oceania (which includes Australia and New Zealand) remains the only geographical region free from the highly contagious strain of H5 bird flu. The emergence of the 2.3.4.4b strain overseas means an increased risk to Australia, due to the increase in the likelihood of entry into Australia via wild bird movements and anticipated increased consequences if it were to enter.
For more information visit our H5 bird flu resource centre.
Avian influenza is a nationally notifiable disease which means if you suspect an animal is showing signs of the disease, you must report it. You can do this by calling the national Emergency Animal Disease Hotline on 1800 675 888.
Note: All Australian jurisdictions also require that all avian influenza virus detections are reported to the relevant Chief Veterinary Officer (CVO).