H5 bird flu is also known as H5N1 high pathogenicity avian influenza. It includes the serious and highly contagious H5N1 clade 2.3.4.4b strain which has been spreading globally since 2021 through the movement of wild birds, with unprecedented impact. H5 bird flu has caused significant illness and deaths in poultry, wild birds and mammals in Asia, Europe, North and South America, and the Arctic and Antarctic. Over 600 bird species and more than 100 mammalian species, including wild marine and land mammals, have been affected.
Oceania region updates:
Australia has confirmed its first detections of H5 high pathogenicity avian influenza (H5 bird flu) in wild birds in June 2026. See Incident – H5N1 high pathogenicity avian influenza (H5 bird flu) in migratory seabirds, Australia - ongoing and birdflu.gov.au for more information.
Management voyages to Australia’s sub-Antarctic external territory, Heard Island and McDonald Islands, in October 2025 and January 2026 confirmed H5 bird flu in wildlife on Heard Island, including widespread mortality in southern elephant seal pups. The findings also point to suspected H5 bird flu impacts on McDonald Islands, with evidence of elephant seal pup mortality. More information is available on the Australian Department of Agriculture, Fisheries and Forestry website.
H5 bird flu is a notifiable disease. If you encounter sick or dead wildlife, you should:
AVOID. RECORD. REPORT.
- AVOID – keep yourself and others safe. Do not make direct or indirect contact with sick or dead wildlife or their immediate environment. Observe from a distance and keep pets away.
- RECORD – make a note of what you observe, including: date and time, location (GPS pin, nearby roads or landmarks, type or description of birds or animals, how many birds or other animals are sick or dead, what they look like (freshly dead or just bones, signs of disease), and if safe, take photos or ideally a video. of animals affected, species/type of animal, location, date and time.
- REPORT sick or dead wild animals via the Emergency Animal Disease (EAD) Hotline on 1800 675 888.
Reporting will alert authorities so they can evaluate the need for testing or other investigation. Even if testing is not undertaken, all reports help inform our understanding of the disease and how to manage it.
Further information
For further information on H5 bird flu, see the Wildlife Health Australia H5 bird flu resource centre and H5 bird flu FAQs.