Biosecurity New Zealand has continued to work closely with Mainland Poultry following the detection of a high pathogenic strain of avian influenza, H7N6, at one of its commercial egg farms in rural Otago.
"Testing has confirmed further cases of an H7N6 subtype of avian influenza in chickens in a second shed at the farm," said Biosecurity New Zealand deputy director-general Stuart Anderson.
"The remote farm remains under strict biosecurity controls to restrict the movement of birds, poultry products, feed, and equipment on or off the property. Detecting further positive cases on the farm is not unexpected given the nature of the virus."
Anderson said the birds in both sheds, which total about 80,000 layer hens, would be humanely culled with the farmer’s cooperation, and this has been planned to start on the 4th of December.
This is expected to take around two to three days using existing industry standard practice of CO2 containerised gas, which farms regularly use to euthanise chickens. There will be no major impact on egg supplies as New Zealand has about 3.9 million layer hens annually.
Once the sheds have been depopulated, they will be thoroughly cleaned. It will be some time before those sheds can be safely repopulated.
“We have Biosecurity New Zealand response staff on-site in Otago, and they are providing advice and guidance, including logistics and planning with depopulation and disposal of the birds."
Testing of other sheds on the property has continued. If necessary, Biosecurity New Zealand will impose more restrictions. However, there have been no further reports of chickens showing avian influenza-type symptoms in any other poultry farm at this stage.
Anderson added that the risk to human health remained low, with no food safety or wildlife concerns.
The property, managed by Mainland Poultry, was placed under a restricted place notice on Sunday after results from testing confirmed an H7N6 strain in chickens from one shed on the property. The virus has likely developed from interactions with local waterfowl and wild birds.
"We acknowledge this is an extremely difficult time for the farm’s operator, but we commend their actions. Mainland Poultry took the right steps by notifying us of sick and dying birds. The farm has strong biosecurity standards.”
Three specialist veterinarians from the Ministry for Primary Industries (MPI) are on site. They have been carrying out further investigations, taking samples from birds in other sheds on the farm, and tracing work to six other poultry farms in the area linked to the affected property.
"We are also tracing all movements to and from the farm over the past week. We will place biosecurity controls on any property if we need to manage any biosecurity risk."
The next steps include continuing to collect samples for testing. The virus incubation period is usually 3 to 14 days, with a possibility of up to 21 days so that testing will continue over the next few weeks.
"Biosecurity New Zealand has a comprehensive surveillance programme of all poultry properties in the area, where we are testing birds on those properties for any signs of avian influenza."
