An animal expert says Mycoplasma bovis "can probably'" be eradicated by 2025, but it won't be easy.
This follows the government announcing it is confident that the cattle disease M. bovis can be eradicated in New Zealand.
Richard Laven, from Massey University's Vet School, told Mike Yardley he agrees, but it will be hard to confirm that it has been eradicated.
"The difficulty is always going to be making absolutely sure that it's not there. That's the issue. The tests are not designed to identify that absence of Mycoplasma bovis, so to be absolutely sure that we haven't got it we are going to have to do a lot of testing, repeat testing and have a lot of testing where it is negative."
"By 2025, if it all progresses as it looks like it's going to, we should be nearly sure that we have eliminated the disease."
He said most infected farms have already been identified.
"Every single dairy farm in the country has been tested six times for Mycoplasma bovis using various tests and the results have come back better than anyone expected, which is that they have not identified any farms, that they weren't already suspicious of, being infected with Mycoplasma bovis."
"So the numbers are looking very good in terms of the total number of farms infected, which means it's likely that there aren't many more out there that haven't been picked up, which means we are probably going to be able to eliminate it."
He said they only picked up three cases of M. bovis, and it was on farms they were already aware of.
"All of those three farms were farms that MPI was already interested in because they had links to farms that were already infected."
"They were identifying those farms through other means so they didn't identify any new farms as being infected."
Laven said it is unlikely that we will see a surge in infected farms following this testing.
"Testing in spring is when we are going to pick up the Mycoplasma in the milk. It's not 100 per cent, even doing 72,000 tests across all the farms in the country you're still not absolutely sure that there aren't farms out there. But what you can say is, it's highly likely that the number of farms is not going to be anything like the 30 or 40 or 50 that people were worried about, so we can say yep from looking at the data I think probably the worst we can expect is another 10 farms being infected that we missed."
Agriculture Minister Damien O'Connor told Tim Dower monitoring of the National Animal Identification and Tracing system has improved significantly since the outbreak.
"We have been following up, we have been sending notices to the farmers who haven't taken the actions needed. They seem to of got the message."
The Government announced a massive response in May after the disease was detected on cattle and dairy farms.
O'Connor says the numbers of farmers affected in some way by the disease is unprecedented.
"There are about 1000 farmers in total who have been tied up in this, a number of farmers and their families have been in the firing line and this has been very tough on them."
Two testing programmes to work out the spread of M.bovis in New Zealand have returned no undetected clusters of disease, and O'Connor believes finding the source may be impossible.
"The report basically says we may never find the source, there are still investigations going on but we we may never absolutely know how M. bovis came into the country."
So far around 180 farmers have received almost $37 million in compensation.
M. bovis, which is not harmful to humans, can cause lameness, mastitis and abortions in cattle.