H5 bird flu has been confirmed in a second Australian mammal, with both detections involving long-nosed fur seals in South Australia, raising concerns about the potential impact of the virus on the state's vulnerable marine wildlife.
The latest confirmation involves a long-nosed fur seal found at The Pages Conservation Park, off Kangaroo Island, after preliminary testing had identified it as a suspected case.
Confirmatory testing has now established that the animal was infected with H5 bird flu, making it the second confirmed detection of the virus in an Australian mammal. Both mammal cases recorded so far have occurred in South Australia.
Second mammal case follows Beachport detection
Australia's first confirmed mammal case was announced on Sunday after a long-nosed fur seal found dead at Beachport, on South Australia's Limestone Coast, tested positive for H5 bird flu.
The animal had been reported by a member of the public on August 19 after it was found dead without obvious signs of injury.
Testing by the CSIRO's Australian Centre for Disease Preparedness subsequently confirmed the presence of the virus.
Just days later, authorities revealed another long-nosed fur seal at The Pages was suspected of carrying the virus.
That case has now also been confirmed.
Concern for endangered Australian sea lions
The location of the latest detection is particularly significant.
The Pages Conservation Park consists of small offshore islands near Kangaroo Island and provides important breeding habitat for marine wildlife, including the endangered Australian sea lion.
H5 bird flu has already been associated with bird deaths at The Pages, and the confirmation that a fur seal in the same area was infected demonstrates that the virus is capable of crossing into mammal species in Australia's marine environment.
South Australia's Chief Veterinary Officer Dr Skye Fruean has said pinnipeds — the group of marine mammals that includes seals and sea lions — share their environment with seabirds, placing them at potential risk of exposure to the virus.
There has not been a confirmed H5 infection in an Australian sea lion, but authorities and wildlife experts are closely watching vulnerable colonies as the outbreak develops.
H5 bird flu spreading through South Australian wildlife
South Australia has been responding to an increasing number of H5 bird flu detections since the virus was first identified in wild birds in the state.
Cases have been recorded across numerous coastal and regional locations and in several species of wild seabird, including greater crested terns, silver gulls, gannets, cormorants and little penguins.
Until the Beachport seal was confirmed positive, Australia's detections had been confined to birds.
The two seal cases represent an important new stage in the outbreak because H5 viruses overseas have demonstrated an ability to infect a range of mammal species.
The South Australian Government says surveillance and testing of wildlife are continuing across the state.
Risk to people remains low
Despite the spread of H5 bird flu among wildlife, health authorities stress that the current risk to the general public remains low.
Bird flu viruses do not easily infect humans, and human infections remain rare.
According to South Australian health advice, people do not need to avoid beaches, parks or other public places simply because birds or wildlife are present.
Walking near a sick or dead animal without touching it is also not considered a significant infection risk.
People are, however, strongly advised not to touch sick or dead birds, seals or other wildlife.
Children and pets should also be kept away from affected animals, feathers, droppings and other potentially contaminated material.
What should you do if you find sick or dead wildlife?
South Australians who see a sick or dead bird, seal or other wild animal should:
- Avoid touching or moving the animal.
- Keep children and pets away.
- Avoid contact with feathers, droppings or body fluids.
- Record the location and details of what you have seen.
- Report the animal to the Emergency Animal Disease Hotline on 1800 675 888.
Authorities say reports from the public are an important part of surveillance and help identify where the virus may be spreading.
No need for panic, but authorities remain on alert
While confirmation of H5 bird flu in a second mammal is significant, there is currently no evidence of widespread transmission among mammals in Australia or transmission between people.
The South Australian Government continues to urge vigilance rather than alarm.
People should avoid direct contact with sick or dead wildlife and report unusual illness or deaths, particularly where multiple animals are affected.
For the latest official information on the South Australian outbreak, residents can visit the State Government's bird flu information service at birdflu.sa.gov.au.