Mycoplasma bovis nearly eradicated – Expert Reaction

The cattle disease which arrived in New Zealand nearly five years ago has been reduced down to a single farm.

It comes after a world-first eradication campaign involving the culling of thousands of cattle, which MPI has described as one of its biggest-ever biosecurity responses. However the Minister for Biosecurity and Agriculture says he can’t rule out occasionally finding M. bovis elsewhere in the country.

The SMC asked experts to comment.

Fiona Doolan-Noble, Senior Research Fellow in Rural Health, University of Otago, comments:

“It is a real positive that Aotearoa has managed to eradicate this disease over the last five years. There is always a downside to these programmes and in this case, apart from the culling of thousands of healthy animals, the human cost has been significant. We are hopeful that recommendations we have made to the Minister and in our publications would help to mitigate the stress to farmers of incursion management.

“Chances of M. bovis returning are definitely a possibility as we have seen with Covid-19, however, there is much greater appreciation across the sector regarding biosecurity we would be hopeful that it would be easier to detect should it return and therefore contain and manage.

Regarding what needs to be done going forward to continue to keep the disease out of New Zealand – the research team I am a part of are not biosecurity experts – but one good thing to come out of reflections on way the outbreak was managed is that government has realised how important local knowledge (farmers and veterarians) is for detecting and managing disease.”

No conflict of interest.

Professor Richard Laven, Production Animal Health and Welfare, School of Veterinary Science, Massey University, comments:

“Undetected spread of bacteria already here is clearly a possibility as not all outbreaks have been definitively linked. However as most have been linked, it would seem to be unlikely. In regard to the disease returning from offshore: as we still do not know how it came in, it is difficult to determine the risk of it coming back. The evidence suggests that it came in via a very low risk pathway, so either our understanding of the risk of those pathways was (and is) wrong or we very unlucky.

“The evidence from the outbreak shows that disease is very rare so if we want to keep out the bacteria, we cannot rely on identifying a disease outbreak (we were ‘lucky’ that diseases occurred early on in the spread). This means we will need to continue surveillance permanently – who will pay for that?

“In any future eradication programme, social science (working with people and approach) needs to be as important if not more so than veterinary science.

“There are other diseases present in livestock New Zealand where the economic return associated with elimination would be far higher than it will be for M. bovis. We should look at putting more effort into eliminating those diseases.”

No conflict of interest.

Dr Helen Beattie, Director, Veterinarians for Animal Welfare Aotearoa, comments:

“I am cautiously delighted to hear that provisional absence of M. bovis has been declared in Aotearoa. The M. bovis Response and then Eradication Programme has faced some enormous challenges along the way, not only due to the nature of the organism itself, but also due to a steep and sometimes bumpy response and then eradication journey.

“Many people across the supply chain, from government to industry leaders, to farmers and their families, to veterinarians, truck drivers, meat workers, and to those developing testing and structuring the response and programme, have been deeply involved and affected by the introduction of this organism.

“Despite some challenges along the way, enormous credit must go to those behind the scenes that have contributed to bringing us to this point – that includes the MPI M. bovis team, those at Wallaceville, and all the amazing social support services that rallied to support what was always going to be a remarkable outcome, should it be achieved.

“It’s important to acknowledge also, the extreme distress, and the emotional and financial challenges that have been part of this eradication, and the loss of many animals for a greater cause. On an individual level, that is extremely difficult to reconcile and accept, and our thoughts should remain with those affected. Reports (e.g. Roche; Paskin) along the way outlined difficulties with the Response that latterly have been addressed by the MPI M. bovis team. Their ability to rally and respond to these criticisms has undoubtedly enabled today’s provisional announcement of successful eradication.

“M. bovis is a difficult organism to eradicate – it’s hard to find in an animal due to intermittent shedding, it’s found in different locations within the animal, it doesn’t always produce obvious disease, and before New Zealand’s response, robust testing methods were not available.

“Widespread surveillance testing via bulk milk and within the beef herd allows cautious optimism that Aotearoa has achieved a world-first. However, given the nature of the disease, and that it is known to be on a feedlot currently, we must remain cautious until such stage as the final farm is cleared of disease, and long-term surveillance confirms a “freedom-from” status.

“To remain free of this disease, scrutiny of biosecurity across our borders is critical. Robust Import Health Standards for animals, equipment and semen are needed that allow New Zealand to protect its imminent M. bovis-free status.

“With challenge, comes growth and learning – included in this category “post bovis,” is a much better understanding of on-farm biosecurity for many famers, and the wider supply chain in Aotearoa. Lessons learned about engaging the local community and their expertise and local knowledge, and having the right people In the right roles, will serve Aotearoa well should such a challenge come our way again. My congratulations to everyone on this remarkable (provisional!) achievement.”

Conflict of interest statement: Dr Beattie is Director of Veterinarians for Animal Welfare Aotearoa, a veterinarian-led group of animal welfare advocates which aims to create better lives for animals by creating influence through advocacy, submissions, education, consultation, and collaboration.

Note: Dr Beattie previously commented on M. bovis in her past role as Chief Veterinary Officer at the NZ Veterinary Association.