Outbreaks of avian influenza
Avian influenza viruses are restricted and prohibited matter under the Biosecurity Act 2014.
Agriculture Victoria is responding to the detection of high pathogenicity avian influenza (HPAI) at commercial poultry farms in Victoria. Movement controls restrict the movement of birds, poultry products, feed and equipment on or off properties in designated areas around the infected premises.
Report signs of avian influenza in birds within Queensland by:
- contacting us online, by phone or in person immediately (business hours)
- calling the Emergency Animal Disease Watch Hotline on 1800 675 888 (after hours).
Veterinarians can submit samples from birds exhibiting clinical signs suggestive of avian influenza virus infection for testing to the Biosecurity Sciences Laboratory.
Highly pathogenic avian influenza - HPAI
Ten outbreaks of HPAI have occurred in Australia since 1976.
Each time, there was severe disease in the affected chicken flocks. All had obvious or circumstantial evidence of contact with wild waterfowl or surface water contaminated by wild waterfowl, or with free-range farmed ducks.
The 10 outbreaks were in:
- Victoria in 1976 (H7N7), 1985 (H7N7) 1992 (H7N3) 2020 (H7N7), 2024 (H7N3), and 2024 (H7N9)
- Queensland in 1994 (H7N3)
- New South Wales in 1997 (H7N4), 2012 (H7N7) and 2013 (H7N2).
Outbreak details
There is some evidence that, initially, low pathogenicity avian influenza (LPAI) may have been involved in the outbreaks in 1976, 1992 and 1997 (Selleck et al 2003).
In November 2012, an HPAI H7N7 virus was detected in a New South Wales free-range chicken layer flock of 50,000 in the Hunter Valley. The property had a range of dams that attracted wild ducks.
In October 2013, an HPAI H7N2 virus was detected in a free-range and cage bird layer flock of 400,000 near Young.
In July 2020, an HPAI H7N7 virus was detected in 3 free-range egg farms in Victoria. All 3 outbreaks were controlled and eradicated, with proof of freedom declared on 26 February 2021.
In May 2024, HPAI H7N3 was detected in 3 poultry farms in Meredith, Victoria and HPAI H7N9 was confirmed at a Victorian poultry farm in the Terang region.
Low-pathogenicity avian influenza (LPAI) (H5/H7)
These LPAI H5 and H7 detections have been recorded in Australian domestic poultry:- LPAI (H7N7) was isolated on a duck farm during investigation of an HPAI (H7N7) outbreak in chickens in Victoria in 1976. The ducks showed no signs of clinical disease.
- Antibodies to H5, H7 and other subtypes of AI viruses were detected in commercial domestic ducks during investigation of an HPAI (H7N3) outbreak in chickens in Victoria in 1992.
- LPAI (H5) antibodies were detected on a Tasmanian non-commercial, multispecies smallholding in 2006.
- An LPAI (H5N3) virus was detected in a free-range duck flock in Victoria during routine surveillance in 2012. The source of the virus could not be determined, but it is speculated that the primary source may have been wild birds, which were freely able to access the range area.
- LPAI (H5N3) was detected in a duck from a flock of backyard poultry (ducks and chickens) in Western Australia in 2013. This was an incidental finding and all 95 backyard birds were euthanised.
- LPAI (H5N2) was detected at 2 turkey farms in Victoria in 2020. LPAI (H7N6) was also detected at an emu farm in Victoria in 2020. All Victorian outbreaks of LPAI were controlled and eradicated, with proof of freedom declared on 26 February 2021.
Low-pathogenicity avian influenza (LPAI) (not H5/H7)
These LPAI (not H5/H7) detections have been recorded in Australian domestic poultry:
- LPAI (H9N2) was detected in a poultry operation in southwestern Western Australia in May 2024.
- Antibodies to LPAI H1, H4, H5, H7 and H9 subtypes were detected in ducks on a farm in Victoria in 1992.
- LPAI (H4N8) was detected on a multi-age, commercial duck farm in Victoria in 1994.
- LPAI (H6N4) was isolated from a single duck on a property in Queensland in 2006.
- Chickens in several sheds from a property in New South Wales tested seropositive to LPAI (H6N4) in 2006.
- LPAI H10N7 was detected in 2010 in a chicken farm in New South Wales, where transmission to abattoir workers during the processing of the poultry was documented.
- An LPNAI H5N3 virus was detected in a free-range duck flock in Victoria during routine surveillance in 2012. The source of the virus could not be determined, but it is speculated that the primary source may have been wild birds, since wild birds were freely able to access the range area.
- In April 2012, LPAI H9N2 was confirmed on a turkey farm housing about 26,500 turkeys in three sheds near the Hunter Valley in New South Wales; the source of the infection is unknown.
- In 2012, LPAI H4N6 virus was found in ducks of several age groups on a multi-age farm of 2,400 ducks located on the north coast of New South Wales.
- In 2012, an LPAI H10N7 virus was detected in a Queensland poultry flock; the source of the infection is unknown, but it is likely that the primary source may have been wild water birds.
Human health concerns
Avian influenza could potentially be a serious human disease but there is limited evidence of human-to-human spread.
To date, the majority of human infections appear to have been transmitted from infected birds.
Human illness and deaths have been confirmed in other countries in people who had close contact with avian influenza viruses (H5N1, H5N6, H7N7, H7N9, H9N2) through contact with infected poultry or their contaminated environment.