You should think about it the same way as with COVID-19
A highly pathogenic strain of H5N1 avian influenza, having swept through bird populations on nearly every continent, has begun crossing into mammals — seals, foxes, otters — raising a question that biosecurity experts in Australia are now asking aloud: not if the virus will arrive, but whether the country will be ready when it does. Carried potentially by the migratory shorebirds that travel annually between Asia and Australia's shores, this virus challenges the comfortable assumption that distance is protection. Like so many threats before it, H5N1 reminds us that the boundaries we draw around our islands — geographic, biological, institutional — are permeable, and that vigilance is the only honest answer to uncertainty.
- A virus that has already killed hundreds of millions of birds globally has now infected over 70 mammal species, including seals confirmed dead in Scotland, signalling that species barriers once considered stable are giving way.
- Australia's relative isolation offers no guarantee of safety, as millions of migratory shorebirds travel annually from Asia along routes that could silently carry the virus to Australian wetlands and farms.
- What makes this strain especially unsettling is its refusal to follow seasonal rules — it now persists year-round, meaning the window of risk is no longer predictable or contained.
- Australia's 2020–2021 avian flu outbreak, which forced the culling of nearly half a million birds across six farms, stands as a recent reminder of how quickly a breach in biosecurity can escalate.
- Federal authorities maintain a low-risk assessment and run active wild bird surveillance programs, but experts stress that monitoring must intensify before migratory birds return between September and November.
- The deeper tension is structural: with 70 percent of the world's bird population being farmed poultry — dense, vulnerable flocks where viruses mutate — the global conditions that amplify such outbreaks remain firmly in place.
A virus that has decimated bird populations across nearly every continent is now crossing into mammals, and Australian biosecurity experts are watching the development with growing concern. H5N1 avian influenza has swept through wild and farmed birds globally, and this week Scottish authorities confirmed that four seals found dead last year had contracted the strain. More than 70 mammals — otters, foxes, minks — have now tested positive, marking a troubling expansion of the virus's reach.
For Australia, the threat arrives on wings. Millions of shorebirds migrate annually between Australia and Asia, and researchers at Deakin University, who examined over 10,000 birds across a decade-long study, have confirmed that waterfowl and shorebirds are common carriers of avian influenza. Marcel Klaassen, chair of ecology at Deakin, drew a deliberate parallel: the situation echoes the early logic of COVID-19 — a virus omnipresent in nature, waiting for the right strain to cause serious harm.
What distinguishes this H5N1 variant is its persistence. Graeme Cooke, Victoria's chief veterinarian, who managed Australia's largest avian flu outbreak in 2020 and 2021 — when nearly half a million birds were culled across six farms — noted that this strain no longer follows seasonal patterns. It circulates year-round, and it is zoonotic, meaning it can jump to humans, as cases elsewhere in the world have already demonstrated.
Australia's federal agriculture department maintains that the country's risk remains low, pointing to its position outside major migratory pathways and its active national wild bird surveillance program. No high pathogenic strains have been detected in Australian wild birds, and testing of inbound migratory birds at the end of 2022 found no evidence of the virus. Poultry, eggs, and meat are declared safe.
Still, the department itself acknowledges that global outbreaks have raised Australia's risk profile. Migratory birds return to Australian shores each year between September and November, and experts are clear that halting migration is neither possible nor desirable. What is possible — and necessary — is stronger monitoring and farm-level biosecurity. Cooke urged poultry farmers to keep their flocks separated from wild birds and to eliminate shared food sources. Australia may be prepared to respond to an outbreak, but preparation and prevention are not the same thing, and the virus is still moving.
A virus that has killed hundreds of millions of birds across the globe is now jumping to mammals, and Australian biosecurity experts are watching the skies with growing unease. The H5N1 strain of avian influenza has swept through every continent except Australia and Antarctica in the past year, decimating wild and farmed bird populations. But what has alarmed researchers most is what happened this week: authorities in Scotland confirmed that four seals found dead last year had contracted the virus. So far, roughly 70 other mammals—otters, foxes, minks—have tested positive for the same strain.
The concern for Australia is not abstract. Millions of shorebirds migrate between Australia and Asia each year, traveling routes that could carry the virus with them. A decade-long study at Deakin University examined more than 10,000 birds and found that waterfowl and shorebirds are common carriers of avian influenza, though the virus can spread to other species as well. Marcel Klaassen, chair of ecology at Deakin, framed the threat in terms Australians understand: "You should think about it the same way as with COVID-19. Coronaviruses are omnipresent but certain strains can cause a problem." The new H5N1 variant is highly pathogenic. It is not a question of whether it could reach Australia, but whether the country is ready if it does.
What makes this strain particularly worrying is its behavior. Graeme Cooke, Victoria's chief veterinarian, managed Australia's largest avian flu outbreak in 2020 and 2021, when six farms—including an emu operation—were forced to cull nearly half a million birds across three separate outbreaks. He noted that the current northern hemisphere strain is unusual because it no longer follows seasonal patterns. It persists year-round. "Normally it would be seasonal, and it is now showing it can persist throughout the entire year," he said. The virus is also zoonotic, meaning it jumps between species. Cases of human infection have already occurred globally, though none have been reported in Australia.
The federal Department of Agriculture, Fisheries and Forestry maintains that the risk to Australia remains low, partly because the country sits outside the major migratory bird pathways. The department operates a national wild bird surveillance program that collects samples from wetlands and other targeted sites, testing thousands of Australian birds annually. To date, no high pathogenic strains have been detected in wild birds, and a recent study found no evidence of HPAI in inbound migratory birds at the end of 2022. The department's website reassures consumers that eggs, meat, and poultry products in Australia are safe to eat.
Yet the department also acknowledges the shifting landscape: "Ongoing outbreaks of H5N1 globally have increased our level of risk for incursions of HPAI viruses of global concern." Migratory birds return to Australian shores annually between September and November. Klaassen stressed that stopping bird migration is impossible—nor should it be—but additional biosecurity measures are essential. He pointed out that 70 percent of the global bird population is farmed poultry, and these flocks are where viruses persist and mutate. "So we should be on the ball to monitor our wildlife," he said.
For poultry farmers, the message is clear: vigilance matters. Cooke urged farmers to maintain strong biosecurity protocols, keeping their birds separate from wild birds where possible and ensuring they do not share food sources. The 2020-2021 outbreak in Victoria showed what can happen when the virus breaches a farm's defenses. Australia is well-prepared to respond to an outbreak, officials say, but preparation and response are not the same as prevention. The virus is moving across the world, crossing species barriers that were once thought to be firm. The question now is whether Australia's monitoring systems and farm protocols will hold when the next migration season arrives.
Citas Notables
The new strain is highly pathogenic and a potential threat to Australia, requiring more monitoring and tighter biosecurity measures.— Marcel Klaassen, Deakin University chair of ecology
The current strain is particularly troubling because it no longer follows seasonal patterns and can persist throughout the entire year.— Graeme Cooke, Victoria's chief veterinarian
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Why should Australians care about bird flu happening in Europe and Asia?
Because millions of shorebirds migrate between Australia and Asia every year, and they can carry the virus in their bodies without dying from it. If the virus arrives on those birds, it could spread to Australian poultry farms, which would be catastrophic for the industry and potentially for food security.
Has this virus already infected people?
Yes, there have been human cases globally, though none in Australia so far. That's what makes it a zoonotic disease—it jumps between species. It's already jumped from birds to seals, foxes, otters, and minks. The concern is that it could jump to humans more readily if it continues spreading.
What makes this strain different from previous bird flu outbreaks?
The main thing is that it no longer follows seasonal patterns. Older strains would flare up in certain seasons and then die down. This one persists year-round, which means it has more time to spread and mutate. That's what worries the experts most.
If Australia is outside the major migratory bird routes, why is the risk considered low?
Geography helps, but it's not a guarantee. Migratory birds still come to Australia between September and November. The department has tested thousands of wild birds and found nothing so far, but they're not complacent. They're actively monitoring because the risk is real, just lower than in other parts of the world.
What can Australian farmers actually do to protect themselves?
Keep their birds separated from wild birds, don't let them share food sources, maintain strong biosecurity. It sounds simple, but it's the difference between a contained incident and a farm-wide outbreak. Victoria learned that lesson hard in 2020 and 2021.
What happens if the virus does arrive in Australia?
The government says it's prepared to respond, and they probably are based on recent experience. But response means culling infected flocks, which is economically devastating and emotionally difficult. Prevention through monitoring and biosecurity is far better than response after the fact.