High pathogenic avian influenza

Readers are advised that the nature of the following content may be distressing.

Global outbreak

High pathogenicity avian influenza (HPAI) is a highly contagious viral disease that can cause severe illness and death in birds. A new strain of the virus, HPAI H5N1, is more concerning than previous strains, as it not only causes mass mortality in poultry but also in wild birds and some mammals. This strain is different from the HPAI H7 strains that were detected on Victorian poultry farms earlier in 2024.

HPAI H5N1 has been spreading across the world since 2021, infecting hundreds of species of wild birds and more than 50 species of mammals.

It has not yet been detected in animals in Australia.

Image: David Paul, Museums Victoria

Risk of HPAI H5N1 arriving in Australia

Due to the global outbreak of HPAI H5N1, there is an increased risk of the virus arriving in Australia.

HPAI H5N1 is likely to arrive in spring or summer, carried by migratory birds from overseas. There is also the potential for HPAI H5N1 to arrive in Australia at any time of year.

Any detection of HPAI H5N1 would require an emergency response to help limit the spread.

Potential impact of HPAI H5N1

If the virus enters Victoria, it is likely there will be substantial wildlife deaths, as has been seen in other parts of the world.

There is no effective treatment for HPAI H5N1 and the prognosis for animals with the disease is poor.

Those animals that survive are usually in poor condition and may continue to shed virus, which poses a risk to other animals.

Although any bird species can become infected, bird groups associated with water are highly susceptible and this includes ducks, geese, swans, gulls, terns, shorebirds, seabirds, pelicans, herons, ibis, cormorants and penguins. Species that live in large colonies of a single species are particularly suspectable.

Predatory birds and scavenger species are also at risk due to the high likelihood they might consume infected animals.

Infected animals experience rapid deterioration in health and can die from the effects of the virus within a matter of hours to days.

Avian influenza rarely spreads to humans but may occur if there is close contact with infected birds, droppings or heavily contaminated environments. Further information can be found on the Victorian Department of Health website.

Signs of HPAI H5N1 in wildlife

The most critical indicator of HPAI H5N1 in wild birds and wildlife is sudden death.

Other signs of HPAI H5N1 in wild birds are:

• lack of coordination, tremors, swimming in circles
• twisted neck or other unusual posture
• inability to stand or fly
• diarrhoea
• difficulty breathing, coughing or sneezing
• swelling around the head, neck and eyes
• cloudiness or change in colour of the eyes.

Reporting suspected cases in wildlife

Reporting will be key to the early detection of HPAI H5N1 in Victoria.

What to do if you find sick or dead wild birds or wildlife with signs of H5N1.

• AVOID contact with sick or dead wild birds or wildlife and their environment
• RECORD what you see
• REPORT to DEECA by calling 136 186, in line with the below guidance

Report clusters of 5 or more sick or dead wild birds of any species, anywhere in Victoria.

Report even one

• sick or dead penguin or pelican
• sick or dead bird of prey, such as hawks, owls, eagles
• sick or dead black swan
• sick or dead marine mammal, such as seals, sea lions, dolphins.

Following a report, DEECA will evaluate the need for diagnostic testing for further investigation.

We acknowledge that this has the potential to be distressing for people. We thank the community for their assistance.

Emergency preparedness

The Department of Environment, Energy and Climate Action (DEECA) is the Control Agency for managing emergency animal diseases, and the department would lead Victoria’s emergency response to an HPAI H5N1 outbreak.

We are also working closely with government agencies, land managers, the wildlife welfare sector, Traditional Owners and other relevant organisations to prepare for a potential HPAI H5N1 detection in Victoria.

There are limited options for responding to the potential impacts of HPAI H5N1 on wildlife.

Our extensive emergency preparedness activities include:

• identifying and prioritising at-risk species and developing detailed response plans
• scenario planning to slow the spread of the virus and manage the impacts of the virus on wildlife
• planning for limited public access to landscapes where there are outbreaks H5N1
• working with the Commonwealth, states and territories to prepare for a potential detection of the highly contagious disease for many months
• establishment of a wildlife-focused Expert Advisory Group to advise on threatened species on priorities for threatened species.

Surveillance

We are undertaking ongoing surveillance for avian influenza virus in wild birds under the National Avian Influenza Wild Bird Surveillance Program which is coordinated by Wildlife Health Australia.

In the event of an outbreak, government agencies would work closely with industry, community, wildlife groups and land managers as part of the emergency response.

Shearwater mortalities

While it is common to find dead migratory birds this time of year, large numbers of dead shearwaters have been found along Victoria’s coastlines during spring.

To date, testing of the shearwaters across Victoria's coastline has not found evidence of HPAI H5N1.

Events such as these, known as ‘shearwater wrecks’, occur occasionally when foraging conditions are not favourable and birds cannot find enough food. It is suspected that starvation is the likely cause.

Shearwaters make long migratory journeys and exhaustion contributes to these deaths, as the birds return to Victoria for their breeding season.

It is important for continued vigilance due to the potential for HPAI H5N1 to arrive in Australia with migratory birds.

We continuing to ask the community to report clusters of five or more sick or dead shearwaters, in line with our reporting guidance.

Following all reports, DEECA will evaluate the need for diagnostic testing or other investigation.

Information for wildlife organisations and wildlife carers

In addition to the above advice, it is important for wildlife shelters and foster carers to be aware of the following.

• It is important to ensure you are complying at all times with your authorisation conditions, including the requirement to quarantine wildlife coming into your care. More information on how to comply with this and other conditions can be found in our Wildlife Rehabilitator Authorisation Guide.
• Moving sick or dead birds or wildlife that are infected with H5N1 could spread disease and put you and other wildlife at risk.
• Maintaining good biosecurity processes minimises the likelihood that the disease may spread from wild populations to animals already in care.

Resources

• Wildlife Health Australia – H5N1 global outbreak
• Department of Health

For information reporting suspected cases of HPAI H5N1 in poultry, and information for poultry farmers and keepers, visit the Agriculture Victoria website.