H5N1 Avian Influenza Arrives in New Zealand and Expands in Australia

H5N1 Avian Influenza Arrives in New Zealand and Expands in Australia

The highly pathogenic H5N1 avian influenza strain has officially breached New Zealand's borders for the first time, triggering immediate biosecurity lockdowns in the commercial poultry sector. Concurrently, Australia's wild bird detections have climbed to 17 cases, including the first confirmation of the virus in a wild non-migratory seabird.

New Zealand's First Detections and Poultry Lockdowns

New Zealand confirmed its first-ever case of highly pathogenic H5N1 on Wednesday, July 15, 2026, in a wild brown skua found at Petone Beach in Lower Hutt, Wellington. This was quickly followed on July 17, 2026, by a second confirmed case in a native kāhu (swamp harrier or harrier hawk) in the Wairarapa region.

Because the swamp harrier is a native land bird and raptor that preys on other species, epidemiologists warn that its infection suggests the virus may already have established an undetected local reservoir. In response, Mainland Poultry—New Zealand's largest egg supplier, representing approximately 40% of the national market—placed over 500,000 free-range laying hens into a precautionary barn lockdown over the weekend of July 18–19, 2026, to prevent contact with wild birds.¹

As of July 20, 2026, New Zealand's Ministry for Primary Industries (MPI) reported that there have been no detections in poultry and no signs of mass wildlife mortality, emphasizing that commercial meat and eggs remain safe.

Australia's Wild Bird Cases Climb to 17

In Australia, the number of confirmed or presumed positive H5N1 cases in wild birds has risen to 17. The vast majority are vagrant migratory seabirds, such as giant petrels, found along coastal areas in Western Australia, South Australia, and New South Wales.

Significantly, CSIRO's Australian Centre for Disease Preparedness (ACDP) confirmed a positive detection in a greater crested tern near Robe, South Australia. This represents the first detection of the H5 strain in an Australian wild non-migratory seabird. Despite the rising count in wild birds, Australian Chief Veterinary Officer Dr. Beth Cookson confirmed that there have been no detections of the virus in poultry or the commercial agricultural production system. The Consultative Committee on Emergency Animal Diseases (CCEAD) has advised commercial free-range poultry producers to house their birds where practical.