New Zealand remains free of HPAI H5N1

​

Avian influenza A viruses infect the respiratory and gastrointestinal tracts of birds, causing them to shed the virus in their saliva, mucus, and faeces. Influenza A viruses can also infect the respiratory tract of mammals and cause systemic infection in other organ tissues. Human infections with avian influenza A viruses can happen when enough virus gets into a person's eyes, nose, or mouth or is inhaled. People with close or prolonged unprotected contact with infected birds (e.g., sick/dead poultry) or other infected animals (e.g., dairy cows) or their contaminated environments are at greater risk of infection. Illnesses in people from HPAI A(H5N1) virus infections have ranged from mild (e.g., upper respiratory symptoms, conjunctivitis) to severe illness (e.g., pneumonia, multi-organ failure) that can result in death.

​

This virus's strains are classified as either low pathogenic (LPAI) - causing no or minimal illness, or highly pathogenic (HPAI) - causing severe illness.

​

In 2020, a new H5N1 strain of the HPAI virus emerged in both domesticated and wild birds across the northern hemisphere. This H5N1 strain differs significantly from other HPAI strains because it spreads more easily between wild birds. (DOC, n.d.)

​

Since 2022, many different wild bird species have been reported with HPAI A(H5N1) virus infection, including terrestrial, seabird, shorebird, and migratory species. In the United States, HPAI A(H5N1) virus detections in wild birds have been reported in 50 states or territories, and outbreaks in commercial poultry or backyard bird flocks associated with high mortality have been reported in 48 states since February 2022. (CCD, 2024)

While the HPAI H5N1 strain is still some distance from New Zealand, it’s important that we take a cautious approach. If anyone sees 3 or more sick or dead wild birds in a group, report it immediately to the MPI exotic pest and disease hotline on 0800 80 99 66.