Two further properties in Waimate and Southland have been confirmed with Mycoplasma bovis, bringing the total number to 20.
The number of properties under restricted place notice, which effectively placed them in quarantine, has risen to 35.
There are now six farms confirmed with the bacterial cattle disease in Southland, 11 in the Waitaki/Waimate districts, two in Mid Canterbury and one in Hawke's Bay.
About 5000 cattle were culled last year from properties in the Waimate district to prevent further spread of the disease.
That operation was completed at the end of December and the Ministry for Primary Industries has deferred a decision on the need for further whole-herd culling until a more thorough picture of the disease's distribution in New Zealand was built.