Avian influenza (bird flu)
In 2020 and early 2021 Agriculture Victoria worked with industry and the community to control and eradicate outbreaks of avian influenza.
There were three different strains of avian influenza, across three local government areas during this incident:
- three egg farms with highly pathogenic H7N7 avian influenza
- two turkey farms with low pathogenic H5N2 avian influenza
- one emu farm diagnosed with low pathogenic H7N6 avian influenza.
Proof of freedom of the disease was declared internationally on February 26 2021.
Surveillance of both domestic and wild birds was a key part of the response and is ongoing.
The surveillance activities helped to establish the virus is no longer present on the farms or in surrounding areas
Avian influenza is carried by wild birds and occasionally can spill over into domestic poultry where it has devastating consequences.
What is avian influenza?
Avian influenza, commonly referred to as ‘bird flu’, is a highly contagious viral infection of birds. Serious forms of the disease can cause severe symptoms and sudden death in domestic poultry (up to 100 per cent of birds). Mild strains of the disease cause few or no symptoms in poultry and may go undetected in some species of birds, though can result in some deaths.
What species are affected?
Domestic poultry, ducks, geese, turkeys, guinea fowl, quail, pheasants, emus and ostriches are most susceptible to being affected by avian influenza. Many species of wild birds, including waterfowl and seabirds can carry the virus but usually show no signs of disease.
How is the avian influenza virus spread?
Infected birds shed the avian influenza virus in saliva, nasal secretions and faeces.
Wild birds are considered the natural host for the virus and usually carry it without showing any symptoms of the disease.
Sometimes the virus spills over from wild birds into domestic bird populations and may cause disease. This can occur through either direct contact between wild and domestic birds, or indirectly through the contamination by wild birds of feed or water of domestic birds.
What are the symptoms?
Symptoms associated with avian influenza can include:
- sudden death
- respiratory distress
- swelling of the head
- purple discolouration of the comb and wattles
- rasping breathing
- rapid decrease in feed and water intake
- decreased egg production
- ruffled feathers
- closed eyes
- occasionally nervous signs.
What do I need to do?
All bird owners need to be vigilant for any signs of avian influenza in their flocks.
Avian influenza is a notifiable disease. This means that legally you must tell us if you know of or suspect the presence of avian influenza in any birds.
You can do this by calling one of the following:
- an Animal Health Officer or District Veterinary Officer at Agriculture Victoria on (03) 4334 2715 (Monday–Friday 9 am – 5 pm)
- the all-hours Emergency Animal Disease Watch Hotline on 1800 675 888.
Good biosecurity practices remain essential to reduce the spread of disease. For more information please see:
Can the virus spread to humans?
The Victorian Department of Health and Human Services has advised that the detected strains of avian influenza in this incident are not a risk to the public. They rarely affect humans unless there is direct and close contact with sick birds. There are no food safety issues identified; properly cooked chicken meat and eggs are safe to eat.
If you have had contact with birds on an affected property and you are experiencing cold or flu symptoms, call your doctor or the Department of Health and Human Services on 1300 651 160 for medical advice.
Risk to Australia
Occasional outbreaks of internationally notifiable highly pathogenic avian influenza and low pathogenicity avian influenza have occurred on poultry farms in Australia.
Each outbreak was quickly detected and stamped out, with only a small number of farms affected.
Annual migration of wild birds has the ongoing potential to introduce new subtypes of avian influenza virus to Australian birds.
Australian response to avian influenza
State and Commonwealth governments and the national chicken meat and egg industries have formal arrangements in place to share the costs of responding to outbreaks of highly pathogenic avian influenza and low pathogenic avian influenza (H5/H7 virus subtypes only) . This helps to ensure that a rapid and effective emergency response can be immediately mounted if the disease occurs.
Owners may be eligible for compensation if birds or property must be destroyed to eradicate the disease.
Procedures for responding to outbreaks generally include:
- slaughter out of infected and in-contact poultry (depopulation)
- strict quarantine
- movement controls to prevent spread of infection
- tracing and surveillance to locate the extent of infection.
Vaccination might be an option in some circumstances but there is no vaccine currently available in Australia.
Wild bird surveillance program
A Wild Bird Surveillance program is in place across Australia, supported by Wildlife Health Australia.