Australia confirmed its first mainland case of Highly Pathogenic Avian Influenza (HPAI) H5N1

¨     Australia confirmed its first mainland case of Highly Pathogenic Avian Influenza (HPAI) H5N1 on 20 June 2026.

¨     The infected bird was a brown skua, found dead in Cape Le Grand National Park near Esperance.

¨     The virus was identified by the Commonwealth Scientific and Industrial Research Organisation (CSIRO).

¨     Testing confirmed the virus belonged to the H5N1 clade 2.3.4.4b lineage.

¨     A second migratory bird, a northern giant petrel, found sick on 18 June 2026, also tested positive for H5N1.

¨     The brown skua was first discovered on 14 June 2026.

¨     H5N1 is a subtype of Influenza A virus that mainly affects birds but can also infect some mammals.

¨     Highly Pathogenic Avian Influenza (HPAI) is a severe and highly contagious form of bird flu.

¨     Before this, Australia had detected H5N1 only on Heard Island in late 2025, making this the first detection on the Australian mainland.

¨     Following the detection, Australia strengthened biosecurity measures across the country.

¨     Authorities increased surveillance and testing of shorebirds.

¨     Vaccination programs were initiated for vulnerable bird species.

¨     Emergency response exercises were conducted to prepare for potential outbreaks.

¨     As of 22 June 2026, there was no evidence of mass wildlife deaths or spread to poultry or agricultural systems.