Despite the growing number of properties testing positive for the cattle disease Mycoplasma bovis the Ministry for Primary Industries (MPI) remains adamant it has the disease contained.
MPI on Wednesday confirmed three new infected properties, two in Southland and one at Ashburton, bringing the total number of properties testing positive to 17, including one in Hawke’s Bay.
The number of restricted place notice properties is 34 and the number of properties for casing is 206.
MPI incident controller David Yard said he still expects more properties to become positive as the tracing and testing programmes ramp up.
“From one Ashburton farm alone we anticipate tracing some 30 additional properties,” Yard said.
All three of the latest properties were closely connected with previously infected properties and were identified through tracing of animal movements.
Because of the increasing number of infected properties MPI would now be publicly notifying infected properties only when there were significant developments such as a positive property in a new region, Yard said.
MPI would continue to update figures on its website and in weekly stakeholder updates.
“When any properties go positive we strongly encourage the owners to notify their neighbours.
“These properties are very obvious to locals as legal restricted place notice (RPN) signs are placed on the entrance.
“Any risk from these properties is mitigated by the RPN they are served with under the Biosecurity Act and this essentially places the property in quarantine lock down.”
Yard said MPI continues to work on the assumption the disease entered New Zealand reasonably recently.
“We are tracing properties from the original cluster (van Leeuwen Group) as well as performing more general surveillance.
“Based on analysis of the likely entry onto the first infected properties we have performed forward and backward tracing of properties which have sold to and/or received animals from the initial infected properties.
“As we find more IPs, we perform the same analysis using NAIT and personal interviews to locate properties sending to or receiving animals from the new IP within the past six to 12 months at the discretion of our tracing team.
“With ongoing developments, including the detection of new infected properties, decisions on future management are currently dependent on the assessment of the emerging picture.”
That included the culling of infected herds.
“The controls in place are adequate until the situation is more clearly understood,” Yard said.
While MPI would now roll out national bulk milk testing in February, six months on from the start of the response, it remained confident its surveillance and testing approach had been appropriate from the start.
“At the outset of the response it (bulk milk testing) was considered secondary in importance to tracing and checking out from the known infected farms, which was the primary goal of the first months of the response.”
In defence of the van Leeuwen Group’s challenge to the MPI claim all infected properties linked back to their initial source, Yard said as the web of infected properties continued to be traced and the understanding of the connections between farms evolved, there were animal movements substantiating MPI’s claim
However, he acknowledged that could change.
“The web of connections between farms in NZ is very complex, therefore, as new connections become clear, our understanding of the situation may change,” he said.
MPI continued to believe it had the disease contained.
“We do not believe the recent positive finds are new spread, rather they are the result of arduous tracing activities which have uncovered animals previously infected by movements from known infected places,” Yard said.