Farmers are on high alert after the first case of Mycoplasma bovis in the Bay of Plenty has been confirmed on a Waiotahi farm.
Federated Farmers Bay of Plenty president Darryl Jensen said the Ministry of Primary Industries (MPI) was investigating after the disease was found from a bulk milk test on the farm near Ōpōtiki.
The farm was being depopulated at the moment, meaning all cattle on the farm were being culled, he said.
He said once that was done there would be a 55-day "decontamination" period, where the property was completely disinfected.
"One case is one too many when it comes to this.
"It's a really horrible thing to happen to any farmer ... the community will embrace and look out for the affected farmer."
Jensen said the disease was mainly spread from animal to animal and likely originated from the infected cow coming from a different farm where the disease was present.
He said MPI would be helping the farmer and putting in hefty protocols to ensure no other farms were at risk.
Neighbouring properties will have been notified and will be keeping their cattle away from the infected property, he said.
A Ministry of Primary Industries (MPI) Mycoplasma bovis Programme spokesperson confirmed a dairy herd in the in the Eastern Bay of Plenty had been infected.
As of late last year, a process was started to depopulate the infected animals on the property, they said.
The risk to neighbouring properties was very low, and they had not seen across the fence transmission in New Zealand.
"There is no reason to believe that because it has arrived on one farm in the Bay of Plenty that it is more widespread in the region, or that it will spread further."
The disease was currently on 30 properties around New Zealand and 196 properties that had the infection have been cleared to return to farming.
As part of the ongoing effort to eradicate Mycoplasma bovis from New Zealand, 130,000 animals have been culled across the country, they said.
The disease first arrived in New Zealand in late 2015, early 2016.