August 2024
In life generally people crave the truth, learn from the truth and act on the truth. Truth is the universal source for learning, where trust develops, and where solutions to tackle the myriad of challenges that life throws at us are fostered.
Yet, we all know that absolute truth is a fickle thing. As time passes, new insights evolve, things change. Gradually we may find that what we thought we knew is conditional on certain things, right only some of the time, or even wrong for a clever reason.
So care is needed, especially with the big decisions where large amounts of money, time and effort are employed to address a particular issue or problem.
Take for example the culling of badgers. A Government expert [1] concluded 20 odd years ago that a very small trial study [2] suggested badgers might spread bTB to cattle, especially if frightened away from the setts where they live, and shooting them would help.
Sounds ridiculous? The entire livestock industry eradication policy in GB and Ireland has been based around ‘badger blame’ for the spread of Bovine tuberculosis among cattle herds for two decades. There has been over £2 Billion of subsequent spending and hundreds of thousands of badgers have been culled around a truth that is now uncomfortable to lose, because so many people have enthusiastically believed and embraced it. They own it, and accepting it is wrong messes badly with what they have said and done over the last 20 years.
The matter came into sharp focus in March of 2024, just weeks before the general election was called, with a Government Agency staff academic paper on badger culling effort [3] in England since 2013. This, followed shortly by a DEFRA Public Consultation [4] aimed at extending badger culling for a decade or more, over further huge areas, but with even fewer constraints on when, where and how.
To the general public this is all a mystery. Surveys show that the public largely think that badger culling ended in 2020 when Government said it was ‘phasing it out’, and the new government’s election manifesto view [5] that it has been ‘ineffective’ means it will stop for good. But actually, in the cold night air, from Cornwall to Cumbria, guns with silencers are steadily slaughtering tens of thousands of badgers each autumn. As harvest 2024 is concluding, the culling is now ramping up yet again.
So what about the truth? Well Steve Barclay MP, the old Defra Minister, one of the few seniors to keep his seat during the Labour landslide, had claimed in an ebullient foreword to the March consultation, that a 56% benefit has been gained after four years of culling badgers down to under 30% of their numbers.
So let’s unpack the truth in that. Firstly, the key time marker in all this is 2016 when the first of ten large cull areas were all up and running and followed by around 60 more at a starting rate of around ten a year. Unfortunately for unpicking science and truth, this was also the time that more intensive cattle testing began ramping up. So telling between the effect of culling and testing is not possible, despite what Barclay claimed.
‘Ah’, say the boffins at the Government Agency for badger culling. ‘But without killing badgers, the cattle tests wouldn’t work so well.’
At this point most people switch off….’ I dunno…suppose it’s possible…I’m not that interested actually….’ It’s one of those speculation moments that is only so interesting given that the facts and alternatives are beyond the non-specialist’s reach and require weeks of fact-checking. This is indeed a complex issue, even for interested parties to consider.
So where did Barclay’s view come from? Well, back in 2012 the coalition government encouraged an academic paper in 2013 [6] that was timed to support badger culling, and that printed its truth, as a part of the justification for mass badger culling. The paper said a few things that we now know were right and wrong thanks to good old Captain Hindsight.
Right, was that the old small study had been rendered meaningless by a horrendous Foot and Mouth disease outbreak in 2001 [7] that mucked up the experiment’s need for ‘stable countryside’ to be able to monitor change in three of the ten areas – enough to spoil the results. The hapless NFU encouraged rapid restocking with untested TB infected cattle, firing up the bTB epidemic.
Wrong were the calculations that rested upon a belief that cattle do not give bTB to badgers. It was thought to be TB moving all one-way, from badger to cattle, that Defra believed in those days, something that was always suspicious and that modern studies now show is wrong [8-11].
And questionable too was a theory, to try to make the numbers add up in a way no one has ever explained and that looks implausible. That theoretical infections going from badger to cattle are somehow passed on more rapidly than those originating from cattle. Baffling?
Lost already? Well to make the old small study work, the boffins believed that while around 94% of disease was the result of cattle-cattle infection, around 6% was down to badgers. Unfortunately, wildlife groups have believed and utilized these figures, despite warnings, not realising it is part of a dubious study that blames badgers and the king pin in justifying the badger culls since 2013. The so called ‘onward transfer’ of infection from badger to cattle is akin to a biblical myth with no scientific legs, yet it became the truth that key people in Government believed. It was held up as the science to believe in, forming and promoting the badger cull policy. Most cull objectors had realised this by 2016.
Back to Barclay’s 56% and the boffins new paper in March 2024. Despite elaborate graphics, this was a pretty rough-and-ready analysis, looking at before and after culling and substantial cattle testing improvements in the first few years of application, and attributing the decline in herd TB breakdowns to a combination of badger culling and herd testing. It stated (twice) that it is not possible to say which factor caused the change. Yet in a discussion of the results it also said the results were consistent with effects of badger culling seen during the small study, and studies using the small studies assumptions, and this speculation found itself in the paper summary (abstract) at the front. This now gives an opportunity for apparent disease benefit to masquerade as fact or truth. Hence Barclay and the National Farmers Union ramped up the rhetoric on ‘Badger Culling Works’, and quoted the 56% benefit as a function of badger culling. Not bTB control – the better description of the mix of things being tried. Without evidence. Sunak picked up the mantle and did the same in a shed with farmers shortly before he lost office at the general election.
But the truth, as pointed out by other senior academics observing, is that these public statements were untruthful. Change might or might not have been assisted by badger culling – the very question the small RBCT study 20 odd years ago was supposed to resolve when it came up with a split answer – it possibly does and it possibly doesn’t. Flip a coin. And the real truth is that badger culling could be having some effect or it might all be down to tougher testing and movement control. Saying badger culling helped from 2013 or was pivotal or a catalyst is a bit like any of the innumerable causation arguments that created problems in science before they were recognized for what they were during the 1960’s [12]. Association is not the same as causation. Would anyone propose that Donald Trump being elected as President in 2016 caused bovine TB to start to fall? Well it happened at the same time, and bTB has come down since………..Or was the fall in TB the result of a general switch to tougher testing?
The problem for truth in this case is that Governments need to make decisions, and where there is uncertainty they need to have a plan. But Government scientists presenting their opinions as fact, for politicians and stakeholders to believe and to repeat, is a deception. A dangerous step and something that needs weeding out by journals employing peer-reviewers. And hopefully not by mournful inquiries years later, charged with working out how it all went wrong. The problem here is that there are few people experienced enough to understand and judge boffin science, and so you find your mate reviewing your work, and you review your mates work, and bad habits develop. Bovine TB science is plentiful and this syndrome sees awkward material published quite often; it provides a good exemplar of the issue called the reproducibility crisis [13]. All the Government scientists need to say is we ‘think’ it might be working because…. that is a long way from saying it ‘is’ – think snake oil salesman. It matters, it matters a lot when lots of lives and money are at stake. It matters because lying to the public is undemocratic and wrong.
So if someone asks you about badger culling, you might just say – ‘well its complicated and I don’t know.‘ But if they pick up a gun to shoot a badger, you might just say ‘hang on – I think you might be breaking the law’. Which requires evidence, and sufficient clarity that mass killing badgers to prevent the spread of bovine TB can be justified. And after 20 years there is no truth to suggest it does, only guesswork. However, cattle testing and movement control has worked in England and Wales without badger culling, so using that proven remedy is justified with some confidence and is an honest approach, if truth be told.
References
1. King, D. 2007 Bovine tuberculosis in cattle and badgers. A report by the Chief Scientific Advisor, Sir David King, to the Secretary of State for Defra on 30 July 2007.
2. Donnelly, C. A. et al. Positive and negative effects of widespread badger culling on tuberculosis in cattle. Nature 439, 843–846 (2006).
3. Birch, C. P. D. et al. Difference in differences analysis evaluates the effects of the badger control policy on bovine tuberculosis in England. Sci Rep 14, 4849. https://doi.org/10.1038/s41598-024-54062-4 (2024).
4. DEFRA 2024 Bovine TB: Consultation on proposals to evolve badger control policy and introduce additional cattle measures. A consultation exercise contributing to the delivery of the government’s strategy for achieving bovine tuberculosis free status in England..
5. Labour Party manifesto https://labour.org.uk/change/
6. Donnelly, C. A. & Nouvellet, P. The contribution of badgers to confirmed tuberculosis in cattle in high-incidence areas in England. PLoS Curr. 10, 5 (2013).
7. Private Eye 2001 Special Report. Not The Foot And Mouth Report. London
8. Biek R, O’Hare A, Wright D, Mallon T, McCormick C, Orton RJ, McDowell S, Trewby H, Skuce RA, Kao RR. Whole genome sequencing reveals local transmission patterns of Mycobacterium bovis in sympatric cattle and badger populations. PLoS Pathog. 2012;8(11):e1003008. doi: 10.1371/journal.ppat.1003008. Epub 2012 Nov 29. PMID: 23209404; PMCID: PMC3510252.
9. Crispell J, Benton CH, Balaz D, De Maio N, Ahkmetova A, Allen A, et al. Combining genomics and epidemiology to analyse bi-directional transmission of Mycobacterium bovis in a multi-host system. Elife. 2019;8
10. Akhmetova, A; Guerrero, J; McAdam, P; Salvador, LC; Crispell, J; Lavery, J; Presho, E; Kao, RR; Biek, R; Menzies, F et al. 2021. Genomic epidemiology of Mycobacterium bovis infection in sympatric badger and cattle populations in Northern Ireland. bioRxiv 2021.03.12.435101; doi: https://doi. org/10.1101/2021.03.12.435101
11. van Tonder AJ, Thornton MJ, Conlan AJK, Jolley KA, Goolding L, Mitchell AP, Dale J, Palkopoulou E, Hogarth PJ, Hewinson RG, Wood JLN, Parkhill J. Inferring Mycobacterium bovis transmission between cattle and badgers using isolates from the Randomised Badger Culling Trial. PLoS Pathog. 2021 Nov 29;17(11):e1010075. doi: 10.1371/journal.ppat.1010075. PMID: 34843579; PMCID: PMC8659364.
12. Hill, Austin Bradford. “The Environment and Disease: Association or Causation?.” Proceedings of the Royal Society of Medicine 58 (1965): 295.
13. Baker, Monya, 2016, “1,500 Scientists Lift the Lid on Reproducibility”, Nature, 533(7604): 452–454. doi:10.1038/533452a