"Less virulent': Buffer zone established around Otago poultry farm after bird flu find

Biosecurity New Zealand has placed strict movement controls on a commercial rural Otago egg farm, after testing confirmed a high pathogenic strain of avian influenza in chickens that has likely developed from interactions with local waterfowl and wild birds. 

“Tests from the Mainland Poultry managed farm have identified a high pathogenic H7N6 subtype of avian influenza. While it is not the H5N1 type circulating among wildlife around the world that has caused concern we are taking the find seriously,” says Biosecurity New Zealand Deputy Director-General Stuart Anderson. 

 “Our testing shows it is unrelated to a H7 strain that was identified in Australia earlier this year and we believe this case may have happened as part of a spillover event, where laying hens who were foraging outside of the shed were exposed to a low pathogenic virus from wild waterfowl.

 “Low pathogenic viruses are present in wild birds here, especially waterfowl like ducks, geese, and swans and the virus can mutate on interaction with chickens.

 “It is important to note that the strain found on this farm is not a wildlife adapted strain like H5N1, so we believe it is unlikely to be transmitted to mammals.”

There were no reports of other ill or dead birds on other poultry farms and there are no human health or food safety concerns. It is safe to consume thoroughly cooked egg and poultry products.

Mr Anderson says quick action was taken in co-operation with Mainland Poultry and a restricted place notice issued.

 “Test results late last night confirmed the strain, but we already had restrictions in place and expert biosecurity staff on site, with more arriving today.  Mainland Poultry took the right steps by reporting ill birds in one shed on the property and locking that building down as testing continued.

 “We will move quickly, with Mainland Poultry, to depopulate birds on the remote property and we’ve placed a 10-kilometre buffer zone around it alongside the restrictions preventing movement of animals, equipment, and feed.

 “We aim to stamp this out like we did with infectious bursal viral disease that affected chickens in 2019,” Mr Anderson says.

“We have put a lot of effort in with the poultry and egg sector, the Department of Conservation, and Ministry of Health to prepare for H5N1 and that puts us in a good position to deal with the less virulent H7N6 strain found on this farm.”

 John McKay, chief executive of Mainland Poultry, which manages the free-range farm says it is committed to taking quick action.

 “We have been preparing for an event like this for some time knowing that low pathogenic avian influenza is already present in New Zealand wild birds. Fortunately, this is not the H5N1 type that has caused concern for wildlife in other parts of the world. International experience with avian influenza has shown us this particular strain (H7N6) can be eradicated quickly and successfully."

Speaking at a media briefing, Food Safety and Biosecurity Minister Andrew Hoggard confirmed the site in question was in Moeraki, adding 40,000 chickens, scheduled for destruction, had been quarantined at a shed on the property.

"Firstly, I'd just like to say really well done to the MPI staff involved for really getting onto this so quickly, particularly over a weekend and coming back so fast with the information and putting measures in place so we can contain this.

"Rapid response is what is needed in these situations to prevent spread. And so we've done a good job here. Just also, you know, I really feel for the farmer involved. Being a farmer myself, it's a huge stress whenever you've got any sort of animal health issue on farm. The whole industry should be grateful for this farmer for reporting and enabling us to get on top of this early."

Minister Hoggard said there was no concerns for the wider food industry, nor was there any fear of an egg shortage.

The immediate concern was to ensure tracing of people and gear from the property, he said.

"We've got measures in place to be trying to get on top of that spread if it was to spread to other sheds and prevent it from moving to other farms.

"At the moment there's been two other sheds or farms that are viewed as potential risks and another, probably four others was due low level medium. So measures are in place in testing or is happening around those other farms."

Main image (supplied / RNZ).