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Prof Malcolm Bennett, Professor of Zoonotic and Emerging Disease, University of Nottingham, said:
“It must be good news for everyone that a review of bovine TB control in England is to be undertaken. It should be uncontroversial that a better understanding of the role of various host populations, including cattle, badgers and deer, plus the role of the non-animal environment (slurry, mud, vehicle tyres, boots etc.) in the transmission of bovine TB, is essential if the infection is to be controlled. There is a range of new evidence, from molecular studies of who-infects-whom to the effectiveness of vaccination of both cattle and badgers, and surveys of TB in badgers (which I have been involved in), that answer at least some of the questions raised in Professor Sir Charles Godfray’s 2018 very thorough review, and so can contribute to policy.
“But many other important questions remain unanswered. Some examples are, how many badgers there are, and where, and for that matter deer of various species (and perhaps other possible hosts?), as well as their infection rates. It’s good to see these mentioned in this statement. Another question, not mentioned, however, is diagnostic approaches in cattle and other hosts and how these might be interpreted in different situations; surveillance without an understanding of the validity of the diagnostics tests in the population being considered, is at best difficult. This question was highlighted in the recent BBC documentary with Sir Brian May.
“For policy, there may lessons to be learned from covid as well, for example in comparing the costs (in terms of human, animal and environmental health as well as economics) of the disease with those of the various control options, and how one size policies (in this case, different host species in different places and environmental contexts) might not fit all. An open debate about these questions would be useful, even if we don’t all agree with its outcome – as the statement points out, bovine TB is currently very expensive for everyone concerned, so understanding why money is spent on different aspects of control is pretty fundamental.
“On the subject of openness, the promise of more detail in the already very useful ibTB online resource is good to see. More openness with the badger population data produced both in the past and in the proposed study, would also be welcome, although there are, unfortunately, obvious issues with making all the details generally available.
“My final comment, of course, is on the meaning of the footnote, ‘existing cull processes will be honoured to ensure clarity for farmers involved in these culls whilst new measures can be rolled out and take effect.’ What does ‘processes’ mean practically? Does this mean new culls will continue, or only existing culls, and for how long? Other than ‘clarity for farmers’, what is the evidence-base for this and what is the evidence base against continuation? Will these questions be looked at early in the review process?”
Prof Lord John Krebs FRS FMedSci, Emeritus Professor of Zoology, University of Oxford, said:
“The new TB strategy recognises that culling badgers is not going to eradicate bovine TB, because most new cases of TB arise from cattle to cattle transmission. This is a welcome shift in policy.
“Accelerating the development of an effective cattle vaccine that allows vaccinated and infected animals to be distinguished will provide a long term solution and was recommended in my 1997 Report. At that time it was thought that it would take about 10 years to develop a vaccine. 27 years later the Government hopes it will take less than 5 years.
“An important missing piece in the press release describing the new strategy is an explicit plan to use more sensitive tests for TB in cattle to help to eliminate the hidden reservoir of infection in cattle.”
Defra press release – Government to end badger cull with new TB eradication strategy
Declared interests
Prof Lord John Krebs: Chair of the 1997 Krebs report on bovine tuberculosis in cattle and badgers.
Prof Malcolm Bennett: Malcolm Bennett studies and teaches infectious diseases, and particularly those of wildlife and that cross species, including to humans. Particularly relevant to this statement is that he supervised a pilot study of bovine TB in badgers in Cheshire, led a DEFRA-funded study of found dead (mainly road-killed) bovine TB in badgers in the Northern Edge, and recently completed a post-mortem study of road killed badgers in the Southern Edge, led by APHA and funded by DEFRA. In addition he has participated in several smaller TB projects involving found dead and culled badgers and other wildlife. All these projects have involved collaboration with a range of farming, badger and conservation groups across England, and in addition to DEFRA have benefitted from funding and in-kind support from those collaborators, charities and the University of Nottingham.