Australia reached a 'devastating' bird flu milestone. What comes next?

The "devastating" H5N1 variant of avian influenza marked a grim milestone on Sunday as the first confirmed case of transmission between bird and mammal species was recorded, with experts warning the worst is yet to come.

A long-nosed fur seal was confirmed to have died of the disease in coastal South Australia, with a second case being investigated in a seal in The Pages Conservation Park islands near Kangaroo Island on Monday.

Earlier, Environment Minister Murray Watt said the country needed to be "realistic" about the impact this illness will have on native wildlife.

"We are likely to see mass mortalities of birds and mammals, and I know that is a very distressing thing for Australians to hear," Watt told ABC television.

Sean Dooley of the avian conservation group BirdLife Australia told SBS News that the virus could have an ecology-shifting impact.

"Potential extinction from the disease is possible for some birds," he said.

"That's why we need an effective response, where we can, to mitigate the losses.

"We also need a massive increase in the resources that go into ensuring resilient populations of as many of our species, or else we're going to be facing a real ongoing crisis beyond the actual outbreak."

How bird flu spreads

Avian influenza, a flu-type virus, is airborne and contracted by birds and other mammals when they breathe or ingest it from an infected animal.

Robyn Alders, an honorary professor at the Development Policy Centre at Australian National University, told SBS News that the virus also survives outside of a host animal.

"Even if you can't see a diseased carcass or a dead animal, it doesn't mean that the environment there is safe," she said.

"Particularly now that we're starting to see areas where you've got larger die-offs, the potential contamination in that area is going to be significant."

In cooler temperatures where water is present, Alders said there is evidence H5N1 can survive for days.

In areas where the virus has yet to arrive, Dooley recommends people continue spending time in nature and report anything they suspect could be bird flu-related to the emergency animal disease hotline.

"That's still really valuable because it can help slow the spread as they remove those birds which are potential sources of infection," he said.

Cats are particularly susceptible to the disease, and Alders recommends people keep their cats indoors as the virus has a "50 per cent" mortality rate for them.

'We're seeing gaps'

Bird flu vaccinations are underway in specific, suitable populations at the moment, but experts question whether the government is adequately prepared.

Dooley said the country is in a stronger position now than it was a few years ago, but that government claims to have "done everything they could" are false.

"We're seeing gaps," he said.

"If you talk to people on the ground ... it's really hit and miss as to whether people have been trained for this, or whether they have the equipment, whether the PPE they need is filtering down.

"There's a lot of people panicking because they don't know what to do and they're not resourced to do it."

Agriculture Minister Julie Collins has said the government is investigating whether bird flu vaccine trials for marine mammals in North America could be used in Australia — but that there is "nothing commercially available" which could protect vulnerable native seals.

Unlike anything we've seen before

While various avian influenza strains already exist in Australia, H5N1 is "so unlike any other bird flu virus we've dealt with", Alders said.

First detected in geese in China in 1996, the strain has flared up in the past but typically burnt out because it is simply too lethal.

The fact the current lineage exists at all is down to human activity, Alders argued, particularly the concentrated nature of poultry farming which creates huge viral reservoirs.

"A virus that kills its host within 48 hours — and that's what it does in chickens — shouldn't survive," she said.

"I don't know where this virus is going, but what I do know is that it was human activity that, in many ways, facilitated this virus to continue and to spread."

She said it's "up to us" to reduce and eliminate the virus.

"Everybody's got to be part of the discussion about how we produce our food, what standards we expect, not only in terms of human welfare but also animal welfare, and really working with agroecological cycles — not thinking that we can cut corners.

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