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Avian influenza

Avian influenza


AVIAN INFLUENZA   - A highly contagious viral disease primarily affecting birds.

Avian influenza (AI) can infect a wide range of bird species including chickens, turkeys, quails, guinea fowl, partridges, pheasants, emus, ostriches, and a large number of aviary and wild birds, especially waterfowl such as ducks, geese and swans.

AI is a nationally notifiable disease meaning any bird or mammal showing signs of disease consistent with AI must be reported immediately via the Emergency Animal Disease Hotline on 1800 675 888 (monitored 24 hours a day, 7 days a week).


What does avian influenza look like?

Signs of avian influenza (AI) infection in domestic poultry and birds can be variable from no obvious signs to sudden death. Affected birds can display any of the following signs:

  • Sudden death or elevated flock mortality
  • Decreased feed and/or water consumption
  • Reduction in egg production or increased number of misshapen or shell-less eggs
  • Watery eyes
  • Sinusitis
  • Darkening of the comb, wattles or legs
  • Swelling of the head, face, upper neck and feet
  • Ruffled feathers
  • Loss of appetite
  • Diarrhoea
  • Neurological signs
  • Sinusitis – an inflammation, or swelling, of the tissue lining the sinuses.

What should I do if I suspect avian influenza?

Avian influenza (AI) is a nationally notifiable disease which means if you suspect an animal is showing signs of the disease, you must report it. If any bird owner is suspicious of AI, they should contact a veterinarian or the Emergency Animal Disease Hotline on 1800 675 888 to arrange for sampling and testing.

If suspect live birds or carcasses must be handled, precautions should be taken such as the use of a facemask, eye protection, gloves and coveralls. If needing to move a bird carcass (e.g. for submission for testing, or disposal) an inverted bag should be used to grasp the carcass for secure bagging.

How is avian influenza spread?

Waterfowl are considered natural reservoir hosts for avian influenza (AI) virus and in many instances can be infected with and transmit AI without showing any symptoms. Avian influenza virus can be rapidly spread by close contact between birds or contact with bird faeces. Movements of contaminated people, equipment and vehicles are also possible pathways of AI spread.

AI viruses are classified based on their ability to induce disease in chickens (pathogenicity) and associated genomic characteristics:

  • High pathogenicity avian influenza (HPAI) is of most concern and has been implicated in 8 outbreaks in poultry in Australia to date (each case was eradicated successfully).
  • Low pathogenicity avian influenza (LPAI) viruses normally circulate through wild bird populations; however, there is risk of these LPAI viruses evolving to become HPAI viruses in domestic poultry. For this reason, it is important to ensure a high level of biosecurity for domestic poultry and birds and prevent their contact with wild birds and waterfowl.

HPAI has the potential to cause significant mortality (death) in wild bird and mammal populations with resultant impacts on biodiversity.  Since 2020 a HPAI of type H5N1 has been circulating through wild bird populations globally, causing significant mortality rates in wild birds, domestic poultry and some wild mammal populations (e.g. marine mammals). Australia has not been affected by this H5N1 virus but remains at risk via migratory bird movements and people and equipment coming from overseas.

Does avian influenza affect people?

Avian influenza is a different virus to the “seasonal flu” which affects humans on an annual basis.

Avian influenza has the potential to infect humans, causing a range of potential symptoms including fever, cough, sore throat, running nose, muscle aches, headache, fatigue and shortness of breath or difficulty breathing. The risk of humans becoming infected with AI after contact with infected birds or bird carcasses is low; however, if suspect live birds or carcasses must be handled, precautions should be taken such as the use of a facemask, eye protection, gloves, and coveralls. If needing to move a bird carcass (e.g., for submission for testing, or disposal) an inverted bag should be used to grasp the carcass for secure bagging.

The risk of humans catching avian influenza from eating cooked chicken meat or egg products is negligible.  Chicken meat or eggs from infected flocks cannot enter the human food chain, and the virus is killed through the cooking process.

For more information about AI and the human health, see NSW Health: Avian influenza in humans (“bird flu”)

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