New Zealand has recorded its first case of highly pathogenic bird flu at an Otago chicken farm, explains Stewart Sowman-Lund for The Bulletin.

To receive The Bulletin in full each weekday, sign up here.

Bird flu detected at Otago farm

New Zealand has recorded its first case of highly pathogenic bird flu, with 80,000 chickens on an Otago farm now set to be culled in efforts to try and stop the spread. As the Otago Daily Times reported, the virus was detected at a commercial egg farm near Moeraki and is believed to have been picked up through interactions with local waterfowl and wild birds. RNZ reports this morning that the virus has spread to a second shed at the farm, doubling the number of chickens that will need to be killed. Crucially, the strain identified on the farm is a high pathogenic H7N6 subtype of avian influenza and not the H5N1 type circulating among wildlife elsewhere in the world, meaning transmission to mammals is “unlikely”, according to Biosecurity NZ’s Stuart Anderson. Nevertheless, officials are taking the presence of the virus seriously with a a 10-kilometre “buffer zone” around the farm and restrictions on the movement of animals, equipment, and feed.

As Reuters reported, we’ve suspended all poultry exports until a point at which it’s believed the strain has been eradicated – at least 21 days. “Until we’ve cleaned up the situation on this farm, and assuming no other issues pop anywhere else, then we will be able to export again,” primary industries minister Andrew Hoggard told RNZ.

Humans not at risk

In an interview with RNZ’s Lisa Owen, virologist Jemma Geoghegan said that the H7N6 subtype can be found in many different wild birds and often doesn’t cause disease – meaning it is low pathogenic. However, when it jumps across to chickens, “it can be highly pathogenic which means they have disease and they can die quite rapidly. It can also spread quite quickly between chickens,” she said. But humans are not at risk from this variant of the flu and it will be safe to continue eating chicken and eggs, so long as proper cooking methods are followed. Andrew Hoggard urged people not to “go out and stockpile eggs”.

In comments to the Science Media Centre, public health expert Nigel French said there was a good chance this outbreak could be contained since the affected farm was found early. However, “vigilance and raised awareness for avian influenza is needed, whether it is for the globally circulating H5N1 strain, or locally evolved strain”.

The bigger picture

This outbreak is clearly cause for concern, but it’s not the strain of avian flu that has had officials here on high alert. So far, New Zealand has evaded the H5N1 subtype of bird flu. That’s despite it spreading from birds to mammals, as explained here by The Conversation, though the risk to humans is considered low. Just a week ago, a child in California became the first American minor reported with a case of bird flu – with 55 infections in humans recorded across the United States this year.

Should it make it into New Zealand, there is concern about the devastation it could cause to our native wildlife, as Virginia Fallon looked at in an excellent feature for the Sunday Star-Times over the weekend. “If the virus gets into our taonga, our treasured wildlife in our captive breeding flocks it would be ruinous,” said Kent Deitemeyer, co-founder of Pacificvet. “We have 245 kākāpō, 300 takahē, and that’s it. It’s taken years and years to bring the numbers up; we cannot lose them.”

The vaccine race

It’s understandable that any mention of a potentially dangerous virus will bring back Covid-19 flashbacks. And much like then, the race is on to get our native bird population vaccinated and ready for the probable arrival of H5N1. As RNZ reported in August, the flu has even made it to Antarctica – probably through the arrival of migratory birds – meaning it is almost inevitable it will eventually make it to our shores. As Michelle Duff wrote for The Guardian, New Zealand is currently in the second phase of a vaccination trial on native birds and early results are highly positive. A small group of birds from five critically endangered species – the takahē, kākāpō, tūturuatu, kakī and one type of kākāriki – were given two doses of the vaccine a month apart, starting in late January.

But some, like Kent Deitemeyer and Jemma Geoghegan, are worried the rollout is too slow – yup, another Covid flashback there. “For the species that will be vaccinated, obviously, it’s a great thing, but use of wider vaccination, not just in wildlife, but in poultry and other animals would help us prepare,” Geoghegan told the Sunday Star-Times.

The current outbreak is a timely reminder that New Zealand isn’t immune and the consequences of a more deadly spread could be devastating. This time it’s chickens, but next time it could be our native birds.