Tests have confirmed the virulent strain of the kiwifruit vine disease PSA has spread to an orchard in north-western Bay of Plenty.
The orchard, at Waihi, is outside the area in the Bay of Plenty where the disease had previously thought to have been confined.
The tests found the PSA-V strain had infected several vines in the orchard.
Terry Richards of the disease management organisation Kiwifruit Vine Health says the orchard has been fenced off as a separate priority zone and the infected vines have already been removed.
Further tests are under way to determine how the disease got there and how extensive it is.
Mr Richards says that, at this stage, his team is looking at the possibility that contractors had spread the infection, or that it may have rain- or wind-borne.
Growers in the region are encouraged to be extra vigilant in their checking of vines.