M bovis programme director Simon Andrew said the latest property to have the infection confirmed was inside the controlled area notice announced in Wakanui, near Ashburton, last week.
The notice was a precautionary measure to restrict the movement of cattle around the infected properties in an effort to stop M bovis circulating in the area.
In May, the government announced that after working to rid New Zealand of the disease, the ANZCO feedlot in Ashburton was the only infected property remaining.
However, five properties have since been confirmed to have the disease, and culling of livestock on the ANZCO property began last week.
It was signalled last month that this new farm would likely test positive.
The fifth property was in the controlled area so the farm had been under movement restrictions since August, Andrew said.
"We continue to make progress in ensuring that we're providing support to the farmers that are affected in the wider community itself.
"That area will be free of cattle from essentially mid-January through to mid March and that will give us the best possible chance to make sure that we remove the infection from the area and enable the community to get back to farming without M bovis."
Andrew remained confident the disease could be eradicated from New Zealand.
