Highly Pathogenic Avian Influenza (HPAI): A(H5N1). What you need to know…

What is it? HPAI A(H5N1) is an avian, highly infectious, respiratory disease. It can lead to death by pneumonia (inflammation of the air sacs in one or both lungs) and encephalitis (inflammation of the brain).

What species have been affected?

  • December 2021: The A(H5N1) virus was detected in a sick wild gull in Newfoundland, North America. Hundreds of birds on the farm died, and the rest were culled. 
  • January 2022: A(H5N1) was detected in wild birds in North and South Carolina, USA.
  • June – August 2022: Hundreds of harbor seals (Phoca vitulina) and gray seals (Halichoerus grypus) died along the coast of Maine, USA, and the St. Lawrence Estuary in Quebec, Canada. 
  • November 2022: Peruvian pelicans (Pelecanus thagus) died en masse along the coast of Peru.
  • January – October 2023: At least 24,000 South American sea lions (Otaria flavescens) died in Peru, Chile, Argentina, Uruguay, and Brazil. 
  • October 2023: About 17,400 southern elephant seal (Mirounga leonine) pups – more than 95% of the colony’s young animals, died in Argentina. 
  • October 2023: Seabirds including the brown skua (Stercorarius antarcticus) and seals including the Antarctic fur seal (Arctocephalus gazella) died on South Georgia and the Falkland Islands. 
  • A few human cases of A(H5N1) have been reported to the World Health Organisation (WHO). Those cases have not resulted from human-to-human transmission.

How is it spread? HPAI A(H5N1) is spread via migrating birds. It is spread locally via direct contact (dense colonies of animals cohabitating, eating infected birds) or indirect environmental transmission (polluted waters). Unlike other avian flu viruses which tend to be picky about their hosts and typically stick to one species of wild bird; the H5N1 virus is unbiased and infects animals from squirrels to skunks, bottlenose dolphins to polar bears, and domesticated animals, such as cows.

How can you detect it? Birds with A(H5N1) have exhibited loss of coordination, lethargy, neck spasms, twitching, and an inability to fly. Seals with A(H5N1) have exhibited difficulty breathing, coughing, lethargy and ataxia (disorientation). Some individuals have also had copious fluid around their noses. 

What do you do if you detect it? If you suspect an animal may have A(H5N1), contact:

  • Ministry for Primary Industries – Biosecurity New Zealand’s Exotic Pest and Disease: 0800 80 99 66
  • Department of Conservation: 0800 362 468
  • Ministry for Health: 0800 400 569

So far, A(H5N1) has not been detected in Aotearoa New Zealand; however, WHO suggests people be vigilant, and avoid contact with infected animals.