H5N1 bird flu moves closer to Australia, New Zealand

The devastating H5N1 avian influenza has travelled 6600km across open ocean to come within striking distance of Australia.

Scavenging seabirds, travelling vast disatances, are most likely spreading the H5N1 virus.

Australia has failed to undertake any testing of wildlife for the high pathogenicity avian influenza H5N1 virus on its Heard and McDonald Island territories this summer, despite French researchers detecting the virus less than 450kms away.

The French team’s testing of sick and dead elephant seals and penguins showed the virus had travelled 6600kms since early last year, from the South Georgia islands, near South America, to the French islands of Crozet and Kerguelen.

The French territory is just 440kms from Australia’s Heard and McDonald Islands, less than 4000kms from Perth and about 5200kms from Tasmania.

The H5N1 virus that has wiped out millions of birds and tens of thousands of mammals has spread 6600kms in just 12 months.

In reporting their findings, the University of Montpellier team stated “with the spread to Crozet and Kerguelen, HPAI H5N1 2.3.4.4b is moving ever closer to Australia and New Zealand, which currently remain free from infections with this strain.

“Our detection… is of global concern as it shows the virus’s ability to spread over exceptionally long distances and across isolated oceanic basins. This implies that the hosts can remain infectious for sufficiently long periods to cover thousands of kilometres.”

The team speculated that the virus may have spread from infected scavenging seabirds, given seals did not start dying until two months after their arrival on the islands.

“Some of the alive elephant seals showed symptoms, mainly convulsion, conjunctivitis, uveitis (inflamed eyes) and nasal discharge. We saw one adult vomiting,” the team reported.

Dead seal pups and adults on the islands of the French Antarctic territory.

The researchers also argued “our results point to a year-long gap in genomic surveillance in the south polar region, obscuring how HPAI H5N1 clade 2.3.4.4b is spreading in the sub-Antarctic”.

A Department of Agriculture Fisheries and Forestry spokeswoman said “Heard Island and McDonald Islands have not been accessed or surveyed during this summer season.

“As a result, no monitoring, surveillance, or testing has been conducted.”

However she stated Tasmania Parks and Wildlife Rangers were running a surveillance program on Macquarie Island, with no cases of H5 bird flu detected to date.

Wildlife Health Australia’s National Avian Influenza Wild Bird Surveillance program has also been testing apparently healthy migratory birds in Tasmania and Victoria over the past three years.

“In 2024, over 700 migratory birds (representing 8 species) were sampled in Victoria and Tasmania by NAIWB surveillance partners from Deakin University and University of Melbourne.

“To date, there have not been any detections of H5 bird flu in any of these events or through targeted surveillance.”