#18,108
Although Australia has yet to deal with HPAI H5, they are wrestling with 4 outbreaks of avian H7N3 and 1 outbreak of H7N9 on poultry farms in Victoria.
While the updates from Agriculture Victoria have been timely, they have been relatively devoid of details. Local media however, has reported in excess of 600,000 heads of poultry culled.
Like everywhere in the world, LPAI viruses circulate in Australian birds. Most are considered innocuous to poultry and humans, but when an H5 or H7 LPAI virus spreads among poultry it can sometimes spontaneously mutate into an HPAI strain.
At this point, it isn't clear how this H7N3 virus has spread to 4 farms in Meredith.
In addition to today's update from Agriculture Victoria, we have WAHIS reports providing additional details. First, today's update:
Current situation
Last updated 07 June 2024 10:10am
We are responding to the detection of avian influenza at 5 Victorian poultry farms.
Four infected properties near Meredith are confirmed to have the high pathogenicity H7N3 strain of avian influenza, and the infected property near Terang is confirmed to have the high pathogenicity H7N9 strain.
Four of the infected properties are located in the Restricted and Control Areas in Meredith and Lethbridge, in the Golden Plains Shire and one is in the Corangamite Shire where movement restrictions were already in place.
All properties have been placed in quarantine and all poultry will be safely disposed of. The sites will be cleaned and cleared of the infection.
The latest detection is not unexpected. It shows that Agriculture Victoria’s reasonable and risk-based Restricted and Control Areas and comprehensive and ongoing surveillance activities are working as they should to pick up spread of the disease.
Housing requirement
We have issued movement controls that include a housing requirement for all birds within the Restricted Areas and Control Areas in Meredith, Lethbridge and Terang.
Under the housing requirement all poultry farmers, backyard flock and bird owners must house or keep their birds enclosed in cages or sheds as much as practical.
Agriculture Victoria staff are on the ground supporting the businesses and working closely with industry to contain and eradicate the virus. Contact tracing is also underway to determine the source and spread of the infection.
Avian influenza is a viral disease of birds found globally. Virus strains are described as low pathogenicity (LPAI) or high pathogenicity (HPAI).
Poultry farmers, backyard flock and bird owners are urged to report any cases of unexplained bird deaths to the VicEmergency Hotline on 1800 226 226.
While cases among humans in direct contact with animals infected with highly pathogenic avian influenza viruses are possible, the current risk to the public remains low. Find out more about avian influenza in humans from the BetterHealth Channel.
Compensation in an Emergency Animal Disease outbreak
In the event of a declared Emergency Animal Disease (EAD) outbreak, financial compensation will be available to livestock owners and business that experience livestock or property losses as a direct result of the disease.
Personal wellbeing
Stressful events can cause feelings of worry and unease, especially where there are levels of uncertainty involved, but there are things you can do to take care of yourself.
The outlier here is the H7N9 outbreak on a single farm in Terang, which so far appears to be contained. This is the first occurrence of HPAI H7N9 in Australia, although LPAI H7N9 exists in local birds (note: this strain is not the same as the Chinese H7N9 virus that killed hundreds of people during the last decade).
The WAHIS Report cites:
EPIDEMIOLOGICAL COMMENTS
This is a confirmed case of H7N9 HPAI in a mixed free-ranged and caged commercial egg layer poultry farm. The farm has a commercial link, through management needs only, with another farm that is infected with H7N3 HPAI (confirmed on 22 May 2024:EVENT ID 5683). H7N9 virus is genetically related to strains detected in wild birds in Australia. Biosecurity controls have been implemented on the farm. A detailed surveillance plan is being implemented and epidemiological investigation and tracing is underway. Operational activities commenced immediately. A Control Area (CA) and Restricted Area (RA) have been declared around the premises. Movement controls have been implemented in the CA and RA. A requirement to house free-range birds where possible has been put in place across the CA and RA. All domestic birds at IP1 - TERANG have been killed and disposed of. Data is current as of 5 June 2024. A public information strategy has been employed. All coordinates provided are approximate to the nearest town location.
The WAHIS Report on the H7N3 outbreaks does not include the 4th farm, reported today. Unlike HPAI H7N9, which had never been reported before in Australia, at least two outbreaks of H7N3 (one in Victoria, the other in Queensland) were reported in the early 1990s.
EPIDEMIOLOGICAL COMMENTS
This is a confirmed case of H7N3 HPAI in commercial egg layer poultry farms. The H7N3 virus is genetically related to strains detected in wild birds in Australia. Biosecurity controls have been implemented on the farm. A detailed surveillance plan is being implemented and epidemiological investigation and tracing is underway. Operational activities commenced immediately. A Control Area (CA) and Restricted Area (RA) have been declared around the premises. Movement controls have been implemented in the CA and RA. A requirement to house free-range birds where possible has been put in place across the CA and RA. All domestic birds at IP1 - MEREDITH have been killed and disposed of. A public information strategy has been employed. All coordinates provided are approximate to the nearest town location. Data is current as of 5 June 2024.
They are not without pandemic concerns, as discussed 11 years ago in mBio: An H7N9 Perspective by Morens, Fauci & Taubenberger.
A reminder that whatever victories we may have against emerging viruses, nature has nearly unlimited resources, a surfeit of time, and always bats last.
