U-turn on phase out? Defra to consult on 100% badger culling.

Eleven years of intensive badger culls in England have left over a quarter of a million mostly healthy badgers, dead using cruel methods. This has been justified on the back of a hypothesis that any infected badgers frequently spread bovine TB to cattle. There is very little science to back this up, and no credible evidence that culling badgers has any effect on cattle TB.

Badger culls aimed to reduce infected and uninfected badger numbers by 70% within cull areas, but population numbers are not known, confounding the basic assumption of the theoretical benefit. Badgers may be wiped out or bounce back quickly, but nobody is monitoring with any accuracy and reporting. This current policy of intensive culling is due to finish at the end of  January 2026. But what happens after that? We may see an attempt to set something up very soon to take over, as the ruins of the current pro-cull government crumbles away with a shockingly bad record on nature protection.

Public consultation on the next phase of Defra’s bovine TB eradication policy has been attempted for over a year, rowed back on, and is now thought to be imminent. The 2020 ‘Next Steps’ bovine TB policy suggested that the follow-on policy would aim to phase out intensive (70%) badger culling, but allow 100% culling (as in the failed Cumbria culling effort) but only in ‘exceptional’ circumstances.

What will these ‘exceptional’ circumstances be?

It seems likely that to qualify as exceptional, a farm or defined area will need to have found a dead badger within an unknown distance which has tested positive for bovine TB or have been found with the same strain of bTB present in the local cattle. However, this proves nothing as the directionality of transmission is not known. You could cull badgers anywhere on this basis. It is not rational. We know that once a strain is introduced by cattle it can rapidly pollute the countryside with TB bacteria for considerable distance.

Such culling attempts have been termed epidemiological culling, or ‘epi-culling’, which is a contradiction as it breaks many epidemiological principles and discredits the veterinary profession.  Already the APHA Risk Pathways approach has been discredited following the successful independent report on the subject in 2023. The reasoning behind epi-culling sets a low bar in simplifying the implication of badgers infecting cattle, when presence of disease in badgers does not prove causation of disease in cattle. It never has done. The problem of undetected bTB in cattle is due to poor sensitivity of the tuberculin (SICCT) testing over decades. Poor testing and unwise cattle movements, coupled with residual infection remain by far the most likely cause of all herd breakdowns. The knowledge of the last ten years points directly towards the paucity of testing, while some researchers twist the evidence to bolster government policy.

It is almost as if this is a pre-planned effort to enable badger culling to become a free-for-all, and this has  been suspected by some, from the beginning. Removal of badger protection by stealth, not science. The licensing method of future culling is unclear and if it is ‘farmer-led’ as the Godfray Report (2018) suggests, what will that mean in practice? Without cull companies and detailed veterinary supervision, the approach could be even more of a shambles than it has been thus far, particularly in terms of welfare. Details of the new plans are about to be made public shortly it would appear.

What will ‘epi-culling’ look like?

Since 2018 APHA have been experimenting crudely with ‘epi-culling’ in Cumbria and Lincolnshire. This new style culling aims to kill 100% of badgers within designated areas but of unclear size. This pilot has failed to eliminate bovine TB however, (see Chapter 5 of ‘A bovine tuberculosis policy conundrum in 2023′ ) and simply served to highlight recurrent infection in a handful of farms and how concentrated testing effort can remove bTB from a few dozen herds. Clearing of these herds by intensive effort will still leave the Cumbria Area 32 a full failure in terms of demonstrating that badger culling can reduce bTB in cattle. This is no model for the future.

Badger vaccination?

Vaccination of badgers may be offered after epi-culling from year 3 as in Cumbria Area 32. This is a massive operation that the NFU may have agreed to in some kind of deal enabling more culling. The entire Edge Area may potentially be available, with cluster areas already having been prepared. Wildlife Trusts and others may, if not careful, become obligated to support and justify the process of culling with the offer of vaccination follow-on. An unwise route, supporting the pretence that vaccinating badgers will help reduce disease in cattle. This is unproven and effectively a unsubstantiated deception that will be a cover for more badger culling, both licensed and illegal. Badger vaccination is likely to be offered for the HRA with possibly more culling – this is the biggest worry of all. We hope not. Badger Groups need to be aware of the risk of being manipulated to promote vaccination projects to farmers under false pretences, which will in effect facilitate more culling to 2038 and beyond.

Is badger culling scientifically justified & has it worked?

The science behind culling is uncertain & becoming unevidenced. A peer-reviewed paper, Langton, Jones, and McGill (2022) failed to find any association between the industry led badger culling 2013 – 2019, and either the incidence or prevalence of bovine TB in cattle herds.

The paper has two main findings. Firstly, data show the slowing increase, levelling off, peaking and then decrease in bovine TB in cattle in the High Risk Area (HRA) of England during the study period, all well before badger culling was rolled out in 2016. This suggests that the cattle-based measures implemented from 2010, and particularly the introduction of the annual tuberculin skin (SICCT) test are most likely to be responsible for declines in disease.

The second finding came from a look at the amount of cattle bTB in areas that had undergone a badger cull and compared it with the amount of disease in areas that had not had culling. This was done over a six year period 2013-2019, so before and after culling was rolled out. Multiple statistical models checked the data on herd breakdowns over time and failed to find any association between badger culling and either the incidence or prevalence of bovine TB in cattle herds. Models that most accurately fitted the data were those that did not include badger culling as a parameter, suggesting that factors other than culling (time, cattle testing etc) were likely to be the cause of the reduction in disease in cattle.

Defra does not accept the findings of this peer-reviewed study but have not produced a credible peer-reviewed rebuttal to it, and (following the change of DEFRA leadership from Richard Benyon to Robbie Douglas-Miller) they still refuse to engage on the matter. They also refuse to release their ‘secret’ and withheld data, and thus-far have not produced their own published science to show that badger culling is effective in reducing bTB in cattle. A preprint (Birch et al 2023) by APHA staff is discussed here and here.

Following on from Langton et al, a pre-print looking at the original RBCT analysis has found that alternative & more appropriate analyses of the data found no effect of badger culling (Torgerson et al. 2023). This is important, because the RBCT has been used as the basis for all culls since 2013. If badger culling during the RBCT produced no measurable disease benefit, the justification for badger culling has no scientific rationale.

What about the ecological impacts of 100% badger removal?

Under Judicial Review of their decision to licence badger culling, DEFRA undertook in 2018 to monitor the ecological impacts of 70% badger removal. This has not happened, with some vague fox count numbers used as a smoke screen. There was cheating and disgraceful behaviour in court in 2022.

So what will be the ecological impact of trying to remove entire populations of badgers, in patchy ways? What will be the licensing requirements for epi-culling and how will species and habitat impact assessments be provided?  How will Tony Juniper at Natural England continue to support culling? Will he keen to keep saying that there is nothing to see?

Despite the frailty of the science behind badger culling, despite the lack of monitoring of the ecological impacts of culling, despite the financial cost and the cruelty, it looks as if the government is about to proceed with yet another ugly and ill-conceived badger culling consultation for its disastrous bovine TB policy.

 

Key badger scientist reviews recent badger culling science

Professor David MacDonald, founder and Director of the Wildlife Conservation Research Unit at the University of Oxford has reviewed the latest science on badger culling in a new report, ‘A Commentary on Current Policy’ for the Badger Trust charity. 

MacDonald, is one of a group of senior scientists at Oxford who advised on and helped instigate the Randomised Badger Culling Trials (RBCT) from the mid 1990’s, work that has been used to inform government policy on bTB ever since. From 2010, this policy has been to carry out  intensive widespread badger culling in the west of England, and it has resulted in the (often inhumane) death of around an estimated  250,000 badgers starting in 2013.

Macdonald who informed but did not take part in the controversial experiments reflects in his commentary, “…it was ‘interesting’ that exactly the same scientific evidence was used to decide, on the one hand, for a badger cull in England, but, on the other, against a cull in Wales”.

Until now, no senior academic has written publicly about the single large-scale published analyses (Vet Record, March 2022) that looked at badger culling outcomes, or about the new uncertainty over the long-accepted analyses of the RBCT highlighted in a scientific preprint by Torgerson et al. 2023 (now published, Torgerson et al 2024). Usefully, MacDonald does both, and has also had a close look at another pre-print by The Animal and Plant Agency (APHA) (Birch et al. 2023), which considers the efficacy of what it calls the ‘badger culling policy’, which is actually a wide programme of cattle testing and movement control measures, of which badger culling was one, rolled out gradually from 2016.

What are the most important points from this new inciteful commentary? Here are several important views that he has expressed:

Walking his way through the publication of Langton et al (2022) in Vet Record, MacDonald recounts the immediate rejection by Defra & the Chief Veterinary Officer of the conclusions of the paper, the subsequent admission of by Defra of their own errors, and the resulting impasse.

Of the Torgerson et al (2023) preprint, MacDonald writes They found that the conclusions of the 2006 analysis are sensitive to the method of analysis used. Indeed, the analytical approach that Torgerson’s team judge to be the most obvious for the purpose, provides no statistical evidence for a culling effect, whereas a model comparison method aimed at selecting a model with the best out-of-sample predictive power indicates that the best model does not include the treatment effect of killing badgers. According to those statistics, killing badgers during the RBCT made no difference to the herd breakdowns, whether measured by either OFT-W or by OFT-W + OFTS.”

Importantly and from a practical governmental perspective he adds:

“Policy-makers reflecting on the statistical merits of these findings should hold in mind John Bourne’s quote (above) about the practical usefulness of badger culling even when the ISG accepted their statistical robustness.

Of the Birch et al (2023) preprint, MacDonald says that the APHA “… do not claim to have measured the consequences of badger culling, and indeed they have not”, and, “there is still no clearcut answer regarding the impact of this approach to badger culling on controlling bTB in cattle or, more broadly, whether it’s worth it.

David MacDonald’s new commentary is, therefore, a welcome review of the latest developments in badger culling science and well worth a read alongside a much longer general report on badger culling produced by the Badger Trust, ‘Tackling bovine bTB together‘. Both reports are available from the Badger Trust website.

Badger scientists at Oxford University who dominated the badger culling review, planning and experiments between 1995 and 2007 have been reluctant to speak out in a comparable way since the 2016 cull roll outs, some because they moved away, others perhaps because they remained involved. The controversy surrounding badger culling may be the reason some steer away from engaging on various elements of the science and the destructive mass killing of Britain’s favourite sentient animal and its young cubs, most of whom are completely healthy. It would be great to see more of the scientists who were involved in the RBCT engage in a similar open way, acknowledging the uncertainty and new learning that suggests badger culling was always irrelevant and unnecessary.

Looking at the big picture, it is worth noting that Defra still have no simple explanation of their concerns about the published 2022 study that showed that badger culling did not reduce bTB in cattle between 2013-2019, let alone a peer-reviewed rebuttal. Following the change of DEFRA leadership from Richard Benyon to Robbie Douglas-Miller (in November 2023), they have again written (January 2024) refusing to engage on the matter. Perpetual secrecy and lack of engagement that bears similarity to the sub-postmasters scandal. Defra still refuse to release their ‘secret’ and withheld data, and thus-far have not produced their own published science to show that badger culling is effective in reducing bTB in cattle. Meanwhile, government Ministers bandy about unpublished percentages of so-called benefit.

Defra’s consultation on the 2020 ‘Next Steps’ badger culling policy

In recent years Defra have made no secret of the fact that they aim to continue badger culling after the current intensive culls finish at the end of January 2026. The 2020 bovine TB policy outlined the intention to continue badger culling in ‘exceptional’ circumstances. APHA have been piloting a new ‘reactive’ style culling policy that aims to kill 100% of badgers, otherwise known as epidemiological culling or ‘epi-culling’ in Cumbria and Lincolnshire. This pilot has failed to eliminate bovine TB however, (see Chapter 5 of ‘A bovine tuberculosis policy conundrum in 2023′ ) and simply served to highlight persistent infection in a handful of farms.

‘Epi-culling’ has been licensed by Natural England since 2018 despite its ongoing failure. Badger Trust was told by Lord Richard Benyon (Minister of State at Defra) in written correspondence, and by Eleanor Brown (now deputy Chief Veterinary Officer) at a meeting, that a consultation on this new epi-culling policy would be launched this year. This now seems not to be the case. In this recent article in VET Times, a Defra spokesperson was asked whether the anticipated consultation would begin before Christmas. The reply was “we are working to provide further detail at the earliest opportunity.”

Initially it was thought that the consultation would be in winter 2022 or Spring 2023. This was delayed to Summer, then Autumn, and then the middle of November. It may yet appear, perhaps this winter, but indications are that Defra are rethinking.

The National TB Conference in Worcester on 29th November might have been an opportunity to set out Defra’s intentions going forward. The programme for the event listed senior speakers/participants including Lord Benyon (Defra Minister), Christine Middlemiss (CVO) and James Wood (Head of Department of Veterinary Medicine at Cambridge), long-time supporter of badger culling. But Lord Benyon did not even turn up, & it was left to a few of the pro-cull vets to make statements on their personal ‘views’ about the success of badger culling. Perhaps they had hoped that APHA’s pre-print on the effects of badger culling might have been published by now. But there are serious issues with this analysis, see here and here.

So why has the consultation on epi-culling been delayed? Are Defra beginning to realise that badgers are not a significant player in bovine tuberculosis after all?

Three possibilities………

  1. The epidemiology of bovine tuberculosis science does not support their position on epi-culling, (see this independent report). APHA’s latest epidemiology report has changed its method of assessing attribution of disease, (see here).
  2. The science behind culling is uncertain & becoming frailer. A peer-reviewed paper in 2022 failed to find any association between the industry led badger culling 2013 – 2019, and either the incidence or prevalence of bovine TB in cattle herds (see Langton et al 2022). Following on from this analysis, a pre-print looking at the original RBCT analysis found that alternative & more appropriate analyses of the data found no effect of badger culling (Torgerson et al).
  3. There will probably be a General Election next year. Pushing out a consultation on a scientifically fragile badger cull policy, that is also cruel, potentially ecologically damaging and economically unsound is not a vote-winner for a political party. A majority of the public remain opposed to badger culling.

Meanwhile, in the House of Lords on December 12th, Conservative peer Lord Colrain, asked “What progress they have made towards identifying a vaccine for eradicating bovine tuberculosis?” Labour peer Lord Granchester took the opportunity to quote a reduction of 51% in herds under restriction in Cheshire, appearing to claim this as a win for badger culling, and suggest  that it would make sense “to allow all areas of England to undertake a cull to control disease in cattle, disease in badgers and stress in rural communities before introducing vaccination?” He failed to mention that Cheshire has actually had more gamma testing than any other county in the country as shown in the bar chart below. It is the increased use of gamma testing that is most likely responsible for the observed decline in herd breakdowns. 

It is still a bit unclear what Labour will do with bovine TB policy if they are elected to government in due course, with their messaging inconsistent at present. Shadow Defra Minister Steve Reed recently told journalists at the Countryside Land and Business Association conference that there is enough reason to believe that badger culling is a way of preventing transmission, so “in the short term we have to continue with that”. Sue Hayman (former Shadow Environment Minister) meanwhile said at the launch of a Wildlife Link report recently, that badger culling would be brought to an immediate end. Current Shadow Environment Secretary Daniel Zeichner was quoted in The Guardian (here) in October saying “I’ve spent a long time looking at this…….We’re going to make England bovine TB free by 2038, but with a range of measures that do not include culling.”

None of this is satisfactory. Secrecy cloaks every move, and stakeholders remain outside what should be an open and careful discussion of the various technological and economic options. It is in no one’s interest to let factional lobbying and secret deals continue with the wasteful and cruel outcomes seen over the last ten years.

We have now reached the point where a handful of pro-cull lobbyists are promoting their ‘views’  on the success of badger culling and making statements that are simply not borne out by the facts. Dick Sibley (a vet who has worked on alternative bTB testing approaches), in a recent letter to Vet Record, comments on “the unfortunate paucity of scientific evidence” that currently underpins current advice, and concludes that “the effect of the mass killing of hundreds of thousands of badgers has been disappointing, to say the least”.

The latest government epidemiology summary shows that half of breakdowns are now herds with embedded disease, herds breaking down for a second, third or more times. Why? Because infection is not being caught by conventional testing. It is not that hard to work out why public money has been frittered over the last ten years on a policy with no end point. It has been deemed just too tough to grasp the nettle and get on with the difficult and expensive job of better testing and some herd depopulation, with farms left fallow for several years. This reality cannot be put off any longer and the economics of a new campaign need to be clear for all to consider, with relevant measures to achieve prompt bTB control, not decades more of subsidised nonsense.

Has APHA finally seen the TB light?

A shift of emphasis

Was it the damning April report on the failed Cumbria badger culls that has led to the clear change in the way that APHA’s is now attributing source of bTB infection in cattle? Have the crazy proposals for the so-called ‘epidemiological culling’ policy been recognised for the epidemiological nonsense that they are?

Or is it simply that the raft of Whole Genome Sequencing (WGS) results clearly indicate cattle movements as the main distributor of bovine TB? Either way, the new epidemiology report for England published this November shows a dramatic shift of emphasis in the attribution of source of infection.

While previous APHA reports have laboured to claim that around half of cattle bTB infections are attributed to badgers, the analysis for 2022 of the results of ‘bovine tuberculosis epidemiology and surveillance in England and Great Britain‘, published earlier this week (20th November) (read here) tells a different story.

Outrageous attribution

It looks like the death knell for the perpetually dodgy and unscientific ‘Risk Pathways’ approach that was so heavily slated in the April report by independent scientists earlier this year. Risk Pathways was introduced in 2017, as evidence to cull badgers across the whole of west England and more. Every APHA ‘epi’ annual report since 2017 has contained a table with the consequence of condemning badgers to more culling.

Now, with the speculative nature of the approach well exposed, APHA have no choice but to do what they should have done before badger culling began – shift emphasis to the necessary cattle testing and herd management. These are the only measures that will actually move bovine tuberculosis in cattle towards elimination using the right cattle tests from the cattle testing toolbox.  

See below in the 2021 analysis: the first column claims outrageously high attribution of source of infection to badgers, at over 50%.

In this years table for 2022 (see below), the column has gone, and the switch to uncertainty is complete.

Compare the pies

Compare also, the pie chart of disease sources from 2021 (below) with that for 2022 (below that). Where once badgers were getting 52% of the blame, 56% is now shown ‘blank’ – effectively showing as uncertain.

What is concluded from this welcome, but far too late in the day revision? The ridiculous blaming of badgers was just too unevidenced, too ridiculous. APHA can no longer deny that evidence now points to the source of bTB infection being all but totally from livestock and livestock infected pastures. And it can only be addressed by livestock measures.

APHA’s hopeless Disease Report Form (DRF) to coax vets into naming badgers as a cause of new cattle infections was heavily criticised by a Derbyshire Wildlife Trust veterinary report in 2019. In their supplementary file, also recently released, APHA now say:

 “A new Disease Report Form (DRF), for recording cattle TB incident investigations, is under development. This aims to enhance data capture and review the methodology around how we assess source attribution to improve understanding of TB transmission pathways and the evidence base for biosecurity advice.”

Whole Genome sequencing can now be used to better understand transmission routes. There is no excuse for anything but bringing all badger culling to an immediate and permanent stop.

Setting out the truth about badgers in black and white

The Northern Ireland Badger Group together with the USPCA has published a new factsheet on dispelling the myths on the role badgers play in the spread of Bovine TB (bTB).  This follows a recent court outcome which has stopped a proposed badger cull in Northern Ireland.

Last month, both organisations welcomed the ruling from a judge that a badger cull proposed by the Department of Agriculture, Environment and Rural Affairs (DAERA) as part of its drive to tackle bovine TB, would now not proceed.

This new factsheet provides dispels the myths on the role badgers play in the spread of Bovine TB.  It adds to a growing evidence base that culling badgers is not the answer to bTB.

Nora Smith, Chief Executive of the USPCA said:

“Last month, we welcomed the court’s decision as a positive step in protecting Northern Ireland’s diverse wildlife and badger population. The unnecessary killing of helpless badgers by free shooting will do nothing to address the problem we have faced for years with bovine TB.

“We have full sympathy for our farming community who have been devastated by the impact of bovine TB on their herds and who have been led to believe a cull of badgers will play a leading role in solving the problem. It will not.

“The latest evidence reaffirms the highest rate of transmission is cow to cow. There must be a new conversation around how we eradicate bovine TB and the focus must be on cattle movements, testing and biosecurity. In Wales, which has a more robust strategy to protecting both cattle and badgers, they have seen a marked reduction in bTB, while their badger population remains intact. 

Mike Rendle, Northern Ireland Badger Group commented:

“The recent court ruling has forestalled the pointless killing of large numbers of badgers in Northern Ireland. It is now beyond any doubt that cattle to cattle infection is driving bovine TB in herds. There is no credible evidence that badgers play a significant role in disease spread.

“The problem lies with the reservoir of undetected infection in cattle. The current skin test, which may detect as few as half of the infected animals in a herd, is not fit for purpose. Farmers and cattle deserve better.

“I hope that by dispelling misconceptions about badgers and instead following the latest scientific evidence, we can all work together to develop an effective evidence-led policy to deal with the disease while protecting farmers’ livelihoods as well as our badgers.”

Read the new factsheet here.

What next for Northern Ireland’s bovine TB strategy?

As Northern Ireland’s Department of Agriculture, Environment and Rural Affairs (DAERA) considers the fallout from the recent court judgement quashing their plan to shoot badgers in Northern Ireland, what does the future now hold for their bovine TB strategy?

DAERA’s current policy carried forward the main elements of the strategy proposed in 2016 by the government-appointed TB Strategy Partnership Group (TBSPG). The TBSPG was a government-industry partnership which included senior industry figures and former civil servants. Notably, no member of the group had any expertise or background in badgers or wildlife.

Soon after its appointment, the TBSPG met with stakeholders to ‘seek their views’. Even at that early stage, the TBSPG made it clear that they thought a badger cull was necessary. There was a clear impression that they had already decided on a badger cull before any evidence-gathering or engagement, meaningful or otherwise, had taken place.

The TBSPG was succeeded in 2018 by another industry-led group, the TB Eradication Partnership (TBEP), under the same TBSPG Chairman. Similarly, the TBEP exhibited equal enthusiasm for a badger cull, with apparent little regard for the views of the badger/wildlife side. You can read about the TBEP membership in this Protect the Wild blog.

Following the recent successful Judicial Review taken by Wild Justice and the Northern Ireland Badger Group, any further attempt by DAERA to progress a badger intervention will require a new public consultation. Given the shambolic nature of the last consultation, any new proposal will require root and branch revision to have any chance of succeeding.

Meanwhile, two major pieces of significant and highly relevant new research have emerged.

Firstly, a comprehensive analysis of bovine TB data by Langton et al. failed to identify a meaningful effect of badger culling on bovine TB in English cattle herds. Instead, reductions in cattle TB incidence and prevalence showed a strong correlation with the introduction of cattle-based disease control measures.

Secondly, a study carried out by scientists at the Northern Ireland Agri-Food and Biosciences Institute (AFBI) found that cattle-to-cattle transmission was by far the most common form of disease spread. Cattle-to-badger transmission was considerably more common than badger-to-cattle transmission, and no badger-to-badger transmission was detected.

The science makes it increasingly clear that ineffective herd testing and the two million cattle movements annually are driving the persistence and spread of bovine TB in Northern Ireland, not badgers. As the body of evidence exonerating badgers builds, DAERA will surely struggle to justify any new badger removal proposal.

As it turned out, DAERA’s (now defeated) decision to implement an indiscriminate and cruellest possible badger cull was a spectacular own goal and a decisive setback to their bovine TB strategy. The responsibility for this debacle lies squarely with the architects of the strategy and those in the industry who supported and enabled it.

Perhaps predictably, the decision to inflict unacceptable suffering on large numbers of healthy badgers served to galvanise the conservation and animal protection sectors in opposition to the plan.

For its part, the badger side has seen its good faith and willingness to engage thrown back in its face. Confidence and trust in the process have been seriously undermined. The government has squandered yet another opportunity to make meaningful progress.

This is a watershed moment for DAERA and the industry. They can choose to embrace the science and tackle the reservoir of undetected infection in cattle, or they can continue to scapegoat badgers and face further legal challenges and delays.

APHA, evidence and distortion – the badger blame game continues

A new analysis of Bovine TB data by the Animal and Plant Health Agency

“Difference in Differences analysis evaluates the effects of the Badger Control Policy on Bovine Tuberculosis in England”, by Colin P.D. Birch, Mayur Bakrania, Alison Prosser, Dan Brown, Susan M. Withenshaw, and Sara H. Downs.

This new analysis was posted as a pre-print on 6th September, on the ‘bioRXive server. You can view it here, although there is no access to the data to check it.

With the current programme of intensive badger culling winding down and coming to an end in 2025, up to a quarter of a million largely healthy badgers have now been killed. A new consultation on Defra’s intentions going forward under the 2020 “Next Steps policy is expected on or after 16th November. This new scientific paper has therefore been constructed at an important moment for the future direction of new bovine TB policy.

Both Therese Coffey (Secretary of State for Environment Food and Rural Affairs) and Lord Richard Benyon (Minister of State for Biosecurity, Marine and Rural Affairs) have said in public and in correspondence that badger culling should continue. Mark Spencer, (Minister of State for Food, Farming and Fisheries), has been using the Birch et al pre-print in parliament to claim large disease reductions from badger culling.

But how certain is the science behind these claims of disease reductions, and the stated intentions to carry on culling badgers?

In a 30 minute presentation available to view on YouTube here, Tom Langton talks through recent scientific pre-prints and publications that have analysed bovine TB in cattle herds and badger culling. Inevitably it is a technical presentation as the issues and the statistics involved are complex. But at this critical moment, as bTB policy is further revised, the controversy and uncertainty surrounding the science of bovine TB control needs even closer scrutiny.

Defra’s last stand?

APHA show a little bit of their hand at last

In March 2022, a peer-reviewed analysis of badger culling data was published in a top veterinary journal. It used all publicly available data.  It showed no detectable difference in bovine TB breakdown between badger culled areas and unculled areas since 2013 (1). Now, after a government information black-out following their look at the data up to 2017, the Defra’s Animal and Plant Health Agency (APHA) have at long last posted a pre-print of their own creation looking at their secretly held data up to 2021.

It is not clear why it has taken so long to release this new analysis, a draft of which was presented at a conference in August 2022 (2).

Cynics might say there has been a search for obscure statistical methods to get the results needed to try to show a badger culling has not been a 100% failure. And of course, it supported the pro-cull rationale to hold data secret and keep quiet about any weakness in policy. This served to enable the 2022 and 2023 killings of over 50,000 mostly healthy badgers, planned and executed by the willing and obedient hands of Natural England (3).

The new pre-print, posted 6th September in ‘bioarchive’ (bioRxiv), is by six members of APHA staff. It tries to use an obscure technique: “Difference in Differences analysis evaluates the effects of the Badger Control Policy on Bovine Tuberculosis in England” to look at Bovine TB breakdown incidence (Withdrawn herds: OTFW) between 2009 and 2020 (4). There are many aspects of this new analysis which are problematic, but here are a few of the more obvious.

A new statistical method of analysis – ‘Difference in differences’ (DID)

This is the first time the DID approach has been used in badger cull analyses and it is simply inappropriate. DID compares the changes in outcomes over time between a population that is enrolled in a programme (a group subject to an intervention) and a population that is not (the control group).

The attempt here is to use the same areas in a ‘before and after’ way. There is no clearly defined control group, it is just the fragmented cull areas before they are licensed to cull. The 52 cull areas are surrounded by and influencing each other during a wide range of tightening testing interventions. They are, therefore, not adequately discrete in space and time, breaking a fundamental DID requirement. So not only is this (DID) an unorthodox approach, but it does not follow the basic rules of the unorthodox approach. It is looking a bit desperate already.

Notably, in the period 2016- 2020, pre-cull and cull areas closely juxta position. Pre-cull and cull cattle testing interventions of course influence changes in adjacent pre-cull and cull areas in an irregular and unpredictable manner, via the constant movement of cattle with different testing and control histories. It’s a mess, and surprising that this has been presented as an appropriate statistical method, considering the subject and the epidemiology involved.

Analysis does not distinguish between different causes of disease decline.

Does the analysis decisively link badger culling to decline in bovine TB in cattle? Not at all. Any possible effect of badger culling is confounded with the continuous multi-faceted and complex tightening of cattle testing that took place in an uneven manner over different and irregular time periods. Some of the very important bTB testing controls used, and the timing of their introduction, are incorrectly described and some of the most important ones are not even mentioned.


The Badger Culling Policy invention

There are places in the manuscript where a claim is made for a link to badger culling, ‘The effect of badger culling…’, but then later this is adjusted to ‘However, this data analysis cannot explicitly distinguish…….’ APHA have stated more than once in their recent epidemiology reports that the cattle breakdown data alone are insufficient to show an effect of culling.

Frankly there is no such thing as the ‘Badger Culling Policy’ (BCP) as framed by this report, beyond just killing badgers. It is an invention trying to characterize extensive cattle testing and movement control measures as just a part of the badger culling bolt-on, rolled out six years after testing control measures had been continuously tightened year on year. To pretend the extensive suite of testing and movement control measures is somehow a part of a whole is just a repeat of the ‘all tools in a box’ nonsense and it deceives. True, some of the more essential measures were increased from the first year of badger culling, but most of them were independent of it and ramped up gradually. So trying to pull them apart in a post-facto try-on will not impress the independent scientist, even if an obliging journal prints it, and industry and Defra promote it with their coterie of academic cheerleaders. Badger culling has just been a pointless distraction to cattle surveillance and control measures to address rampant cattle-to-cattle transmission.

So again, no, the analysis is not able to show causation by badger culling of any change in disease, and Defra and APHA’s judgement could be seen ill-judged by trying to convince anyone that this is credible. It is as clumsy as the Chief Vet’s apologies and efforts on Radio 4’s Farming Today in 2022. Defra boss Richard Benyon has been claiming big figures for badger cull benefits for years, but this does not provide any evidence for them.

What is the ‘true burden of disease’?

The new analysis has a surprising and unconventional interpretation of the ‘true burden of the disease’ or disease ‘prevalence’ in a population. It suggests that ‘incidence’ is the better indicator of true burden, which they must surely understand flies against first principles. It is ‘old thinking’ based on the out-dated views of farm vets who claimed that only visibly lesioned cows are infectious.  Yes, incidence  has been one unit of disease measurement, and it was the unit used by the RBCT to claim a benefit for badger culling. But science has moved on, and this is a strange attempt to live in the past.

The interpretation contrasts with APHA’s reports and understanding of disease controls if you look closely. It contrasts with the conclusions drawn from better comprehension of the SICCT (skin) test sensitivity and specificity, which has been clarified in recent years. Gamma IFyN testing has revealed a very significant reservoir of undetected reactors (diseased animals) in bTB infected herds, pointing towards undisclosed infection in undetected herds too. This ‘hidden’ reservoir in cattle that remains is what really matters for disease understanding and control. The true burden is bigger than the known breakdowns and identified reactors, why else would the disease persist? Both here and in Republic of Ireland where badgers have been relentlessly persecuted and SICCT and Gamma testing has failed for decades.

So why exactly did APHA attempt this clumsy redefinition of the ‘true burden of disease’. Perhaps because it needs to try to defend the original RBCT analysis which by controversial statistical modelling (5), managed to suggest a relationship between incidence and badger culling, having failed to find a relationship with disease prevalence. The effort applied to carry on killing badgers is deeply disturbing.

But wasn’t bovine TB already reducing before badger culling began?

Levels of Bovine TB were falling in many areas soon after annual SICCT testing was introduced in 2010. And well before culling started in most areas. However, the new APHA analysis reduces the analysis of pre-cull data to one data point. This conveniently helps to conceal the significant pre-cull decline and masks the true disease trajectory and results. A logarithmic scale is also used to distort visual effect. Not unlike methods used in the earlier Brunton and Downs reports.

Recent Edge Area data added into the analysis for what purposes?

The new analysis mixes data from 46 High Risk Area study areas with 6 from the Edge Area. These have very different epidemiological and disease control history profiles and the reason for mixing them is not explained. It looks like a deliberate attempt to manipulate the data. Pre-cull gamma testing was intense in the Edge Area. While the manuscript mentions additional gamma testing from 2017, gamma testing was erratic between areas and over time. There were considerable numbers of gamma reactors in many of the cull areas in cull years 1 and 2 of culling with similar disclosures levels to years 3 and 4, but pre-cull use in the HRA was generally low. Mixing them may give you a result you like, but it can be seen through for what it is.

In both HRA and Edge areas, bTB incidence was declining when many of the additional disease control rules were intensified, and badger culling introduced. The addition of this extra data makes it even more impossible to distinguish effects of badger culling and disease control measures that are known to drive down bTB.

Attempt to dismiss peer-reviewed 2022 study published without mentioning it

A comment in the text of the new pre-print says that it is not possible to match badger culled and control areas. This is not only incorrect but unevidenced, with unsubstantiated claims. The 2022 published and peer reviewed study that used this methodology effectively has not been cited. There is no mention of the even more obvious alternative to their complex DID approach, which would be to simply match a series of individual farms in culled and unculled areas. This approach is only available to APHA, which holds all individual farm records confidentially. Such simple monitoring could and should have been an expected outcome of a High Court ruling that required the government to ‘adapt and learn’ from badger culling. Why has it not been done? Perhaps it has been done but gave the wrong results?

Distinct lack of clarity

There is a definite need for clarity in the analysis presented, including the Appendix. This does not seem to be the output from the constrained DID analysis, but something else that is not fully described in the methodology. Analysis uses the lesser known system called STATA (nearly all analysts use R-code).  The data is not supplied, and the Stata code is not supplied, so no one can replicate what has been done here. An author, when contacted, said these would be available following publication of the paper. Too late for others to comment on?

Does this draft show that badger culling has reduced bovine TB In cattle?

No, it doesn’t. Because the methods are inappropriate, the results are flawed, and so the conclusions are wrong. There is no way to distinguish between different interventions and change in herd breakdowns since 2013 with the approach taken. Might these results be misleading and deceive if published? Yes. Why has such a flawed analysis been produced now? Is it a try-on to justify Natural England’s new autumn badger blood-fest? Will Defra contractors, grant recipients and a friendly journal whisk it through peer review with recommended friendly reviewers? Probably.

A consultation on culling all badgers over wide areas is being cooked up despite previous policy promises. One could speculate that APHA have been told both by bosses and lawyers that they need to produce evidence that the culling policy has not been a complete waste of life, public funds, and other resources including masses of police time. They are desperate to do this, and get it out right in front of the move to ‘carry on culling’. This preprint aims to be the new truth about badger culling, but it’s all smoke and mirrors.

References

  1. Langton TES, Jones MW, McGill I. Analysis of the impact of badger culling on bovine tuberculosis in cattle in the high-risk area of England, 2009–2020. Vet Rec 2022; doi:10.1002/vetr.1384
  2. DEFRA called out over flawed bovine TB claims at international vet conference
  3. Bovine TB and Badgers: a weakened link
  4. PREPRINT: Colin P.D. Birch, Mayur Bakrania, Alison Prosser, Dan Brown, Susan M. Withenshaw, Sara H. Downs Difference in Differences analysis evaluates the effects of the Badger Control Policy on Bovine Tuberculosis in England.  bioRxiv 2023.09.04.556191; doi: https://doi.org/10.1101/2023.09.04.556191
  5. PREPRINT: Paul Torgerson, Sonja Hartnack, Philipp Rasmusen et al. Absence of effects of widespread badger culling on tuberculosis in cattle, 13 December 2022, (Version 2) available at Research Square [https://doi.org/10.21203/rs.3.rs-2362912/v2]

Post-Normal Science – Fact, Fantasy and the BBC (again)

A quick look at the BBC farming media and sociology, touching on ‘tribalism’, the BTB Partnership and ‘avoiding the facts’. The result: a perfect storm to confuse bovine tuberculosis control.


In 2022 DEFRA took steps, but failed, to try to stop published peer-reviewed science being published in the Veterinary Record (here, here, here and here), disgracefully interfering in the scientific process. Fourteen months later, DEFRA are still unable to produce data or analyses to substantiate their claim that badger culling has resulted in any disease benefit, or indeed has not failed completely. The Minister Therese Coffey now talks about badger culling continuing if the science is good‘ (see here).  Last year, the Chief Veterinary Officer Christine Middlemiss on Radio 4s Farming Today, blamed others in DEFRA for the withholding of data on badger culling (listen here). If such data were released, it would quickly  allow the use of a wide variety of analyses to check for the efficacy of badger culling. Surely the BBC’s influential Radio 4 flagship farming programme Farming Today, with its one million listeners, would wish to be first to get to the bottom of what is really happening in the badger cull, which is after all, such an important subject. But recent events suggest that they are perhaps, more than hesitant, and might even prefer confusion over clarity?

This month, following enquiries to Farming Today about a misleading story on badger culling by David Gregory Kumar (a BBC reporter from the West Midlands), a follow-up piece was promised by the BBC’s Dimitri Houtart, their ‘Environment, Food, Rural Affairs & Natural History Executive Editor & BBC Rural Affairs Champion’. He said: ‘I have asked my Farming Today team to ensure we mention your complaint and highlight your main points’  On the offending programme on 4th July, Gregory Kumar had played a clip where James Griffiths, a livestock farmer from the Gloucestershire Pilot 1 badger cull area had said ’badger culling has undoubtably made a difference, no one can deny it.’ With Gregory-Kumar then adding, ‘the latest data seems to support this.’ Which it does not. The latest data shows bTB falling generally as it has since around 2015, but the role of badger culling, unseparated from the increased use of better disease tests, is not known. The only published science, checked by a large raft of independent experts, suggests that it has not worked (read here).

Oddly, Gregory Kumar had mentioned the apparent inability of Defra to show badger culling works in an online article that day (see here), reporting a Defra line that analysis of the cull data was not possible due to a lack of comparison sites. This is misinformation because there are many ways to compare Defra’s secret data inside and outside cull areas each year since 2016 to give valid comparison analyses. Is it that Defra don’t get the results they want, or is it that for some reason they are incapable of doing the statistics in question? At least the Secretary of State is referring to ‘if’ the science is good. But the apparent delay in producing good scientific evidence of the benefits of culling is curious. Meanwhile, the government tries once again to bundle a further raft of badger killings through in August to perpetuate the miserable fiasco. Thousands and thousands of completely healthy adult and cub badgers will be killed for no good reason while farmers and the public are misinformed.

Sadly, in this recent episode of media confusion, history was repeating itself, with Gregory Kumar grossly overstating the case for the badger cull working and providing misleading information in the same way on a BBC outlet.  Back in 2014 the BBC Editorial Complaints Unit (ECU) partly upheld a complaint against an article that Gregory Kumar wrote on BBC NEWS online, as follows: here is a part of the ruling on Gregory Kumars work:

The committee began by looking at what data there was to support the belief that a badger cull had led to a reduction in TB in cattle.

Given that both the statistics and scientific studies about the link between badger culling and bovine TB levels were inconclusive, the Committee examined whether the article had used clear and precise language to make this apparent to the audience. In doing so, it observed that the badger cull had become a highly divisive issue with those for and against the cull using the findings of different trials to bolster their respective causes and so it was essential that the BBC provided the greatest clarity possible on the subject.

In this context, the Committee believed that the language used in the article had not been sufficiently precise as it suggested that the badger cull might be a factor in helping control the disease when this was scientifically unproven. It considered that, while the data did show a decline in the number of cattle infected with TB in Ireland, there was no conclusive evidence to show that the badger cull had been categorically responsible for any of this decline and so it was inaccurate to say that, along with other measures, it can help control the disease.

On July 4th 2023, misleading information was again given out suggesting that badger culling had worked in Gloucestershire and England, with bTB policy in Wales (without culling) not working so well. However, the epidemiology reports (here) show an influx of diseased cattle into north Wales from Shropshire and Cheshire, providing a simple explanation for this. Local trading is still around 50% of cattle movements in Wales.

Here is the data from Gloucestershire where James Griffiths farms:

There has been an increase from 22 incidents in 2013 when badger culling began to 28 incidents in 2022. It is not hard to spot that badger culling shows no sign of working.

So, Defra persist in withholding data that could tell us if badger culling is working, and continue to allow exaggerated claims for efficacy to be made. And what did Farming Today do to clarify the situation? They got in touch with DEFRA, and on 17 July played bits of an interview with a member of its secretive BTB partnership, Professor Gareth Enticott of the Human Geography Department at Cardiff University.

The bTB Partnership Group was set up in 2021, with the aim ‘to encourage shared ownership, coordination, and decision-making surrounding England’s 25-year bovine TB eradication programme’. In 2022, its chairman John Cross (who has just been given an OBE) when asked its view on a new scientific analysis, said that the group does not have the capacity to consider scientific evidence. This was a surprise as it counts a professor of epidemiology amongst its membership. Other members of the group are largely farmers and vets who believe that badgers should be culled. Wildlife and nature conservation experts are not well represented.

Disappointingly, rather than addressing the point of contention in the previous Farming Today, i.e. whether or not the latest bTB data support the thesis that badger culling is reducing disease in cattle, Prof Enticott introduced the concept of ’post-normal science’. This did not really feel like an appropriate response to a factual and statistical matter concerning real data and the withholding of it for simple analyses. Enticott contended that Farmers may not be keen to wait for data to show that badger culling is effective – was that deemed acceptable?  He said words to the effect:

“ …science is never definitive on anything, and that’s how science progresses, that there’s always debate about what works and what doesn’t work. In terms of the badger cull and TB policy as a whole, what you’ve got really is a debate about values which are in contest with each other, so the evidence which has been collected around badger culling reflects a set of different values about what constitutes appropriate evidence, and those values represent or are reflective of the times in which the evidence was collected.

So if we go back 20 – 25 years, you know there was a real hope that the randomized badger culling trial, very scientific approach – that form of evidence seemed to be the kind of the highest level of scientific evidence would provide the answer, and would also convert people into believing that badger culling would work. Now it turns out that that wasn’t actually the case and it wasn’t the case because they’re always these kinds of uncertainties around badger culling. But you can look at that in a number of different ways and always challenge it. So there’s never really going to be a definitive answer.”

This is simply misleading. The RBCT, as a scientific exercise, was aimed at finding out it culling could provide any disease benefit, rather than trying to ‘convert people into believing that badger culling would work’. The recent learning curve from better understanding of testing efficacy is that the ‘all-reactor’ set of results should be used in the analyses; these show no relationship between badger culling and herd breakdown. These comments reduce the conversation to confusion with a jaded view of the science process.  Enticott went on:

“The answer really is what kind of science do you want to have. So, in other another environmental controversies people talk about the need for what’s called kind of post-normal science. You often have an issue where the facts are uncertain, values are disputed, the stakes are high, but people need to make a decision quite quickly. Waiting for the evidence of the randomized control trial or whatever, is not going to be appropriate.”

Firstly, the facts are not uncertain (although the interpretation certainly is), and the normal science process is open for business, it is just Defra don’t want to let go of data, talk about analytical procedure or publish results because they just want to carry on killing badgers. There never was any hurry, everyone knew that bTB was spread long distance in lorries and the skin test was not clearing herds properly. The reality was a conscious policy choice to carry on ‘trading dirty’ rather than lock down, while blaming the badgers. Enticott continued:

You need to develop different ways of collecting information and doing science, and people refer to that as post-normal science. Now one of the ways in which you might do that is by kind of accepting that you know different forms of evidence are limited and there are problems with them.”

Well, anyone interested in post-normal science is welcome to Google it. It looks like a bit of a neo-liberal mandate to make it up as you go along. Promoted by an ‘International Society for Ecological Economics’…… While it can be appreciated as a kick-back on the current trend to twist data with dubious modelling, it looks like the kind of rationale that could be used to help reduce the planet to dust.  You must wonder if Farming Today’s million listeners were given a clear insight into the concept and its application to bovine TB control.

This must be an example of the BBC at its worst and you have to wonder what Gregory-Kumar and Dimitri Houtart are up to.  Do they know what they are doing or are they just two more of John Krebs sticky people (see here)?

Gareth Enticott articulated that farmers hold their own views on the effects of badgers on biodiversity and would be keen to take control of badger numbers for that reason, which is very revealing but not very helpful. Any move towards farmer-led/informed manipulation of the ecosystem remains illegal because of the barbaric treatment of wild and domestic animals by a range of sadistic people. The legal protection of badgers was a move that reflected the wishes of the public in the 1970’s who had witnessed decades of sickening abuse. Animal welfare, like science, progresses by careful process. It marks out some measure of human progress and humility. The role of badgers in the ecosystem would be much better understood if Natural England and DEFRA had done what they promised a High Court Judge they would do in 2018 and monitor the ecological consequences of removing hundreds of thousands of them. But that has been strongly resisted, and substituted with feeble ‘rule of thumb‘ assumptions.

The effectiveness of badger culling as a disease control measure remains unproven, and this is what needs to be communicated to the farming community effectively. Then they can stop wasting their own, as well as public money on a badger culling policy that is expensive, and ultimately has not had, and never will have, any measurable or actual impact on bTB in cattle.

Back in 2012, ‘Bourne’s carrot’ was the phrase developed from the rumoured whisper in a Westminster corridor, to John Bourne, who ran the RBCT. The metaphorical carrot offered killing badgers to help incentivise farmers to test and remove infected cows. We have had a long era of Fake News and ‘winner takes all’ mentality.  Can the truth prevail? Not with post-normal science one suspects.

Since 2011, there have been books exposing government incompetence in livestock disease management (1) and the jumping to conclusions by social analysts on the advice of vested interests (2). There has been the cautioning by an exiting Chief Scientist on ‘tribalism’ and its drug-like ability to bring civil servants into conformity (here).  The farming and veterinary sectors, alongside vested academia still struggle to come to terms with the reality that badgers are not implicated in any significant spread of Bovine TB in cattle herds.  Which players will be the first to accept the wickedness (here) of the situation, and will the media finally spot what is ultimately in the best interest of farmers, cows and badgers? Has post-normal science been hiding in plain site since 2011 – it looks decidedly possible. Will BBC Farming Today and other farming media be able to cope? Probably not on current form – we will see.

A full transcript of the Farming Today piece from 17th July is available here.

(1) Why were you Wicked to Badgers?, May 2022.
Book Review:  A History of Uncertainty – Bovine Tuberculosis in Britain 1850 to the Present,  Peter J Atkins, 2016, Winchester University Press
(2) Book Review: Vermin, Victims and Disease. April 2020.  British Debates over Bovine Tuberculosis and Badgers, by Angela Cassidy

What is going on with bovine TB in north Wales?

Some observers may have noticed bovine TB breakdowns figures for Wales have levelled-off in recent years. For the first time in a long while they are showing a divergence away from the progress of herd breakdown trends that until recently was largely parallel with England.
See the data here

And here:

Since 2021, north Wales has experienced an uptick of bovine TB breakdowns in two areas in north Wales, which is causing a levelling of national decline. Looking at the genomic (spoligotype) data indicates that this upsurgence of disease originates from cattle movements from the English border counties of Shropshire and Cheshire, dating back to 2017. Radiating local movement of disease (local trading) within the ‘Low’ and ‘Intermediate’ TB Areas North, in Wales, has pulled down the overall progress compared with England.  Wales introduced enhanced measures and increased testing sensitivity several years before England, resulting in its downward trend. But this has now been held back and it has nothing to do with badger culling.

While bTB control has been compromised in two areas of Wales, in 2022  England saw a welcome steeper decline in 0TF-W  breakdowns as the use of 6-monthly SICCT testing and gamma interferon to better identify infected cattle began to take effect. Gamma testing raises herd testing sensitivity from around 80% (of the SICCT test) to perhaps  90% or more, halving the numbers the tuberculin test misses but has around 4% false positives. This is one reason why 6-monthly SICCT testing has been preferred as it also detects more than a single annual SICCT test. The additional 6-monthly SICCT tests were introduced in Shropshire and Staffordshire from March 2021 and in the rest of the HRA from January 2022. Defra have had issues updating their data recently, but it now appears that  in the HRA cattle tests increased from around 4.61 million 2021 to 5,44 million in 2022 an increase of approaching 20%. 

However, APHA data shows how, alongside, gamma testing bit into the main  driver of disease – persistent herds, often with large numbers of cows and cow sales each year and infecting many new herds each year through local and auction sales. The big breakthrough came in 2019 with over a quarter of a million gamma tests across the HRA and Edge with a 30% drop in persistent herds across the HRA and Edge. 

Further, for 2019, Defra followed the example of the Welsh Government and applied a 50% reduction in compensation for animals moved into a TB breakdown herd that were subsequently removed as TB reactors or direct contacts before the herd regained OTF status. Gamma testing was used in England at considerable levels from 2018-2022 in the HRA, and the disparity became more visible from 2020 as Wales became infected from the English Edge Area.

Peer-reviewed analyses show that in England  there is no sign of benefit in the HRA from badger culling. The rate of decline of bovien TB disease prevalence in England’s High Risk Area (HRA) now matches the level of fall of 20% per year seen in the 1960’s, when the disease was quickly brought under control using cattle based measures. Had gamma testing been introduced earlier as in Wales and the Republic of Ireland, the English epidemic would have been well under control by now.

Six-monthly SICCT testing and use of Gamma testing will disclose more infected cows that escape the testing system and bring bovine TB down, but may not finish the job. A more sensitive and specific  blood test such as Actiphage will be needed to do that. Cattle vaccination may also play a role too but with a disciplined approach to testing, may be avoided.

Is APHA’s approach to bTB control negligent?

The annual bovine TB epidemiology reports (1) for England and Wales, both compiled at APHA Weybridge, have historically had authors in common. More recently however, the reports no longer publish the identity of the authors. Why might this be? What we see now is a definite disparity in approach, presentation and implication.

The emphasis on wildlife and Risk Pathways Analysis (RPA) in the England reports is noticeable, compared to the Welsh versions (Table 1) which barely mention them. So whilst bTB is clearly the same disease in both countries, the attribution to wildlife, cattle movements and residual infection differs very markedly as you cross Offa’s Dyke.

*Wales not yet reported

Table 1. Mentions of the risk pathways approach and badgers and wildlife as a source of  bovine TB infection in APHA reports for Wales and England 2016-2021. Note near absence of mention for Wales, while England has a growing obsession over wildlife involvement.  Will attempts be made to force Wales to follow England’s scientifically unreferenced pathway?

These differences have occurred due to the use in England of un-evidenced data to support a policy that culls badgers in England, whereas in Wales no such policy exists (2).  RPA was introduced in 2015 by APHA on a trial basis by vets using the newly updated Disease Report Form (DRF), and with the stated aim of identifying the source of bTB breakdowns, defined as ‘hazards’. In this trial, the pathway by which disease entered the bTB infected herd was to be decided by the investigating vet. The DRF provided a list of epidemiological hazard options to select; the option of attributing disease to wildlife was the default where attribution to a cattle source was not immediately obvious. The trial was quickly hailed as a success and expanded in 2016 with a few changes. In 2017 it was adopted by APHA as a standard recognised procedure for identifying the source of an infection, training vets to routinely misdiagnose.  

Risk Pathways; a process hijacked by pro-badger cull advocates

APHA have not been able to provide scientific citation to validate the use of RPA protocol. Despite claiming since 2019 that they have a supporting paper in preparation for peer review and publication in a scientific journal, over three years later this has not appeared. It could perhaps be argued that RPA has all the hallmarks of being constructed by APHA to facilitate and support widespread badger culling, because that in effect is what it has done.

Since 2017 RPA has become the primary tool to implicate badgers as the source of the majority of incidents in England (2,3). Wales, in contrast, cites cattle movements, residual cattle herd infection and poor cattle purchasing decisions as the primary sources of bTB herd infection.

A trawl through recent APHA English County bTB reports reveals a plethora of statements about badgers which are not supported by qualifying scientific evidence. Many of these are stated as if they are settled science (they are not), or with descriminatory language. Below are a few examples from the Executive Summary of the APHA England 2021 epidemiological report (4) :-

“Eradication of bovine TB requires control of infection in both cattle and the main wildlife reservoir (badgers).”

“In 2021, as in previous years, herds located in the HRA (where there is high infection pressure from cattle and badgers),…….”

“For England, the source of infection with the highest weighted contribution was badgers (49%), followed by ‘Other or Unknown’ sources (17%). The most frequently considered sources of infection in the HRA were badgers (52%) and ‘Other or Unknown’ sources (16%). In the Edge Area, badgers constituted 52% of the considered source, followed by cattle movements (17%).

The existence of local reservoirs of M. bovis shared by cattle, badgers and other species; wildlife reservoirs of M. bovis are more common in the HRA and the western and northern parts of the Edge Area.

Compare this with the extracts from the Executive Summary Wales Bovine Tuberculosis Surveillance Report 2020 (5), where there is not a single ‘wildlife’ reference.

The risk of a herd becoming infected with TB is associated with factors such as herd density, herd size, production type, TB history and location. These factors contribute to the spatial pattern of TB in cattle herds across Wales. Dairy herds had a significantly higher TB incidence rate compared to beef herds, with this effect remaining after adjusting for herd size and location. Similarly, herds with more than 300 animals have the highest incidence rates, with this effect remaining after adjusting for herd type and TB Area.”

“The increase in recurrent infection (a TB incident occurring within the last two years) in cattle suggests this remains an important driver of infection in Wales.

Use of antibody blood tests increased by 85% in 2020 compared to 2019, with 11-13% of tests disclosing reactors in the high TB areas, west and east, intermediate TB area mid Wales.”

From 2017 onwards, the England epidemiological report has a map illustrating the areas of England where badgers are considered by (what is described as) “informed veterinary opinion” to be the source of bTB infection. This is veterinary opinion that has been informed by APHA’s flawed briefing of vets.The map suggests that badger contribution far outweighs that of cattle. Combined with DRFs, from which the map data is derived, it offers no evidence to support this veterinary judgement. There is a clear bias towards blaming badgers. It even references “infected badgers” within the text, with an admission from APHA that no badgers have been clinically tested.

There have already been 10 years of intensive badger culling in England, and there appears to be some intention to continue with so-called ‘epidemiological culling’ into the future, despite a lack of evidence as to efficacy (6). APHA’s epidemiological assessments try to justify this new style epidemiological culling, by ‘finger pointing’  badgers as the source of breakdowns.

Unscientific perpetuation of wildlife involvement persists

The unscientific claims of wildlife involvement in bTB persist. They are being pedalled via epidemiology reports that lack scientific evidence and backed by vested industry and veterinary interests. The speculative blaming of badgers as a source of bTB infection in cattle, without scientific evidence or justification, seriously undermines the whole bovine TB eradication policy.

APHA pride themselves on being a world class science establishment, supported by such statements as :

Science continues to be fundamental to everything APHA does and we are committed to high quality science-based evidence for decision making and policy development. We will deliver this strategy over the next five years.

The new model for epi-culling is not quite the model of scientific rigour APHA aspire to. Is it more a clear case of confirmation bias, remoulding and manipulating information to support a government policy that has tried to normalise removing large numbers of healthy badgers from the English landscape, contrary to high quality science based evidence and to correct handling of uncertainty and precautionary principles.

It has to be asked, has this manipulation been intentional? Is incompetence or even negligence the right perspective? Will public opinion continue to be ignored? Who exactly is pushing biased procedures? What level of pressure is being exerted from vested interests, and who is routinely interfering with government science?

References:

1. APHA 2022 Bovine Tuberculosis in England in 2021 Epidemiological analysis of the 2021 data and historical trends November 2022.

2. Griffiths, L.M., Griffiths, M.J., Jones, B.M., Jones, M.W., Langton, T. E. S., Rendle, R.M., & P.R. Torgerson. 2023. A bovine tuberculosis policy conundrum in 2023. On the scientific evidence relating to the Animal and Plant Health Agency/DEFRA policy concept for ‘Epidemiological’ badger culling. An independent report by researchers and      veterinarians to Defra and the UK Parliament.

3. Critical evaluation of the Animal and Plant Health Agency report: ‘Year End Descriptive Epidemiology Report: Bovine TB Epidemic in the England Edge Area – Derbyshire 2018, E. Wright BVSc Cert VA Dip (AS) CABC MRCVS & S. Mayer BSc BVSc PhD MRCVS.

4. APHA 2021. Science Strategy 2021-26.  Expertise with Impact. Online strategy.

5. APHA 2020. Epidemiology of bovine tuberculosis in Wales. Annual surveillance report
For the period: January to December 2020.

6. Langton TES, Jones MW, McGill I. Analysis of the impact of badger culling on bovine tuberculosis in cattle in the high-risk area of England, 2009–2020. Vet Rec 2022; doi:10.1002/vetr.1384

Bovine TB and Badgers: a weakened link

A new article in the May issue of British Wildlife magazine provides an overview of the current state of affairs with badger culling in England, and a welcome update on the science surrounding the issue.

It looks at new work that questions the role that badgers play in bovine TB in cattle, and what the most likely reasons behind the perpetuation of the disease are.

It also looks at the problems that badger culling is likely to be causing to the ecosystem in general, and whether or not this is being adequately monitored or mitigated.

There is a potted history of legal challenges to the badger cull, and a view on the insight and benefits that this difficult work has provided.

It looks at where the current government intends to take the badger culling policy next, and what ‘epidemiological culling’ could mean for our badgers in the future.

You can access a copy of the article here, for a charge of 99p.