MPI says it “strongly suspects” the third farm is positive for the disease, identified for the first time in New Zealand on first one then a second farm in the Morven area, near Oamaru, in mid-July.
Both farms are part of the 16-farm Van Leeuwen Dairy Group. The third farm is also in the Oamaru area and has a direct connection with one of the infected VLDG farms, having received some animals from it before the discovery of the disease.
MPI’s director, response, Geoff Gwyn, said that as a result the property is now under a restricted place notice, controlling the movement of animals and other risk materials off the farm.
Gwyn said the new development is not a sign the disease is running rampant in NZ but is evidence of the extensive surveillance and testing programme working.
“This is not a game changer for us. Along with the animal industry bodies we remain committed to continuing the biosecurity response, finding any infected properties, controlling the disease and, if possible, eradicating it from the country.
“The disease is being well contained on the known properties and we are confident our control measures are sufficient to contain it there. Our surveillance programme continues to investigate whether the disease had been spreading around the country before it was discovered in South Canterbury,” said Gwyn.
In a stakeholder update email, MPI said movement tracing from the farm showed that before the response animals had moved to 14 farms. MPI had already contacted and taken samples from many of those farms and was contacting the others urgently to arrange testing.
MPI was aware of persistent rumours of other infected properties but was tracing all reports and emphasised that there were only three positives, as of August 23.
Federated Farmers biosecurity spokesman, Guy Wigley, said it was always anticipated there might be more positive tests. The stock movements had occurred before the disease was identified and so were legitimate.
Quite a number of other farms were on the same pathway and also needed to be tested, he said.
“At this stage it still looks as though it is containable. It’s not out of containment because all these properties are in their sights. There are a known number of properties, so I’m still optimistic we can contain and eradicate this disease.”
Wigley said the positive result on the third farm did not make the task harder, but meant the tests were working. All-negative tests would have been a bonus, but further positives were to be expected.
Wigley praised the response of MPI and the vet, Merlyn Hay, who originally raised the alarm.
“MPI came in after the disease had been cycling for perhaps six weeks at least before the penny dropped that this was a new organism that hadn’t been seen here. So all credit to the vet involved who managed to join the dots, because it’s a very difficult disease to identify unless you apply the specific test looking for it. And if it’s not a disease that’s already here it’s not a test that you apply, is it?
“I think when we look back in hindsight we might say the testing should have started earlier or that we should have had the testing equipment on hand,” said Wigley, “But can you have testing equipment on hand for every exotic disease that’s overseas and not here already?”
MPI has estimated that 33,000 tests will have to be completed before they can know the extent of the outbreak; it is getting through them at a rate of about 3000 a week.
“They know the mountain that’s in front of them,” said Wigley.
Gwyn said there was no need to name the third farm concerned.
“The farmer has been in regular contact with us and has voluntarily kept stock and risk goods on the farm for more than three weeks while our testing has taken place.
“No animals have left the property since July 20. However it is understood that before this some animals were moved to a number of other farms. MPI is contacting those properties and is testing animals with urgency.”
Gwyn said there is no clear evidence that disease is on these other properties. MPI was considering whether the farms would need to have specific controls placed on the movement of risk goods.
