Monday, June 25, 2007

Stitch-up, revisited

A comment on our posting a year ago, where a Somerset landowner, who is also a MRVS veterinary surgeon gave his views on the execution of the RBCT dispersal trial, made us sit back and think.

Not ususally supporters of 'conspiracy' theories - we tend to err on the side of egos and their associated and inevitable cock-ups - but could the RBCT been done any differently? Why was it so designed to inflict on groups of badger the very methods which would give a known result? It was certainly not as Krebs originally intended. But now, a convenient airbrush has diluted that all important 'Cull all badgers' in a Proactive area, and 'Cull all badgers in response to confirmed Tb in cattle' to a mere 'population reduction'.

We re-post both the article from John Cohen, BVetMed, MRCVS and today's comment on it.

"As a landowner in one of the 'trial' areas, I had the dubious pleasure of being invited and attending Professor Bourne's meeting to explain the aims and implementation of the Krebs trial to landowners. His presentation was fluent, forceful and full of spin. During the presentation, he pontificated on some events in the history of badger / bovine TB in Dorset. Unbeknown to him, these were events that I had been personally involved with and knew full details of.
It was very educational to me.

I realised that he was describing the facts in a strictly accurate - yet totally misleading - way, so the impression given was the opposite to the truth."

That the trial is severely flawed - in my opinion, fatally so - is self evident to any objective scientist. A sound experiment, for that is what the 'trial' purported to be, depends on knowledge of, and control of, all the variables. This trial had no control.

In the 'proactive' areas no culling took place during the lactating periods, and 20 percent of the babgers were left behind. It would seem that there was, effectively, not a great deal of difference between proactive and reactive areas.If one allows for the unofficial culling that took place in the no treatment areas, these results are skewed. No matter how the statistics are applied the conclusions drawn can be challenged by a competent sixth former.

Over the past 25 years or more, many veterinary officers have diligently collected masses of data on thousands of breakdowns, and have had their work scrutinised by a sceptical mini panel. All that work, together with that of the veterinary investigation officers, has been effectively been ignored by both Krebs and Bourne. The results of the inquiry and the trial appear to have more to do with egos of eminent men, than science or truth. Bourne's insulting personal response to the points raised by Paul Caruana is no less than I expected from this most arrogant of men."


That broadside, with which we fully agree, was launched by John Cohen, BVetMed, MRCVS of Chard, Somerset, and printed in Veterinary Times, June 12th. 2006

And a comment on this from one of the Wildlife team operatives (we guess) working with The RBCT, came the following insight :

"Well, you've really been stitched up by John Bourne and his scientific report this time !

As one of the staff working on the Krebs Trial, we all knew John's views before the trial really got underway. He had always said, as he does now, that the problem lies with cattle. "It is a cattle disease and it has to be treated this way" is what he has always subscribed to. Both he and Chris Cheeseman clearly wanted the result that they have now delivered - kill infected cattle, leave infected badgers alone !

Were the results made to fit their theories? It does make you think !

How can that possibly be a way forward ? The source has to be removed, or we had all just as well give up cattle farming once and for all ! The article written by Paul Caruana, one of the Wildlife Unit's more sensible and realistic field officers, said it all- but where did it get him? ( he was disciplined for those who didn't know) before he left Defra last year. After he submitted his article, both he and the majority of the wild life Unit's managers were summoned to meet with Ben Bradshaw. They unanimously agreed what a waste of time the trial had been, and that things should have been done much more efficiently and effectively. None of them gave credence to the results that came out of the trial. If that doesn't tell you what a farce the Krebs Trial was, nothing will.

There is a way forward for all concerned. PCR technology, coupled with Government paid pre/post movement testing will do the trick. Target sick badgers, sick cattle, have the reassurance of the gamma interferon test behind you and , hey presto, things will surely improve ?! Clearly, to all of us, there is no political will to get on top of this disease, as has been shown by the sacking of all of the Wildlife Unit staff before Krebs was even finally reported. They do not want any part in the culling of sick badgers, and that is unlikely to change without some fierce and voiciferous lobbying from the farming community, the NFU and all other interested parties.

Something has to happen, and soon. Ten years have been wasted on the Krebs trial, with outcomes that have affected us all. More badgers, more TB, more financial hardship, worse morale in the whole of the farming community- what has to happen before somebody in Government has the guts to make the decision that is needed ?
I am in total despair over it".


This comment rang some disturbing bells. In 1997 one of our contributers heard Dr. Cheeseman of CSL's Woodchester Park, tell shell shocked cattle farmers at a Cheshire meeting that they could not separate Tb infected badgers from the cattle herds on which they depended. "Where you are farming cattle, you are essentially farming badgers; they predate on cattle habitat." And answering the question of biosecurity, Dr. Cheeseman delivered the bombshell: "You can't " he said, "you get rid of your cattle".

That was after describing the effects of peturbation on diseased communities of badgers, the levels of infection they carried and possible transmission opportunities. Which is why we say the RBCT told us nothing we didn't (or Cheeseman et al didn't, know before). We are told that Dr. Cheeseman repeated his "Get rid of cattle" blast at an October meeting in 2006.

And that is a most extraordinary statement for a government advisor to make.

21 comments:

Anonymous said...

John Cohen writes "there was, effectively, not a great deal of difference between proactive and reactive areas"

So why were the results different between those two arms?

The trial, which *is* a trial according to dictionary definitions so none of these silly scare quotes please, has told us that this type of culling will be at best ineffective and at worst counter-productive. Yes of course it is possible that an alternative policy would have a different effect, but do not pretend that you can do anything other than speculate about that.

Matthew said...

Anon:9.58
You ask: "So why were the results different between those two arms?"

We cannot speak for Mr. Cohen, but from personal experience of the RBCT, if the 'cull all badgers' methodology had been carried out effectively, then the results should have been similar.

We know from PQ's that the Proactive areas were given priority, particularly after the lay off in 2001. Reactive culls were years behind - if they happened at all - and then they were abandoned in autumn 2003.
But both were subject to only 8 night cage trapping which bagged the scent markers and the strongest, (if they bagged anything at all) leaving behind a shattered group of the weaker members, to reassert their territory.

"The trial ...., has told us that this type of culling will be at best ineffective and at worst counter-productive."

Quite right. It has.

But outside the Krebs triplets, which 10 years ago were the worst hotspots for TB, and right across to west Wales where there was no RBCT badger dispersal, the situation after a 10 year moratorium on dealing with infected wildlife is far worse. I think one can asuume that in these areas badgers were left alone, courtesy of a tweak in the law of the land. And we don't think even John Bourne would claim his 'edge' effect extended for hundreds of miles - or maybe he has.

Anonymous said...

uh?

I find this very hard to understand indeed. The comment by matthew does not respond to the original post.

And the comment re the experience outside the triplets is also irrelevant. The situation here could have got worse for all sorts of reasons. It is mere speculation as to which (as the original poster pointed out), because there is no control. Contra Mr Cohen, there was a control arm in the RBCT.

Yours (a different) anonymous

Matthew said...

We find it most confusing with all these different 'Anonymouses' or is it anonymi?' But thanks for the comment, different 'anonymous'.

Did you mean 'original post' or the Anon. comment on that?

When we post letters and comments from other sources, we cannot, nor will not attempt to answer for their writers. If appropriate, we may give an overview of our own experiences at the sharp end of the RBCT.

We beg to differ re the areas outside the Krebs triplets. If Bourne is correct then his efforts within the zones and the so-called 'edge effect' outside them are extremely relevant to what has happened, and what is in store, for the rest of the country. We watched as colleagues across the country now do, as Tb adavanced on their herds at 3 - 6 miles/ year.

As we have said, a line on a map is a heroic gesture but only for today.
Infected animals do not read or adhere to such deliniation, and very soon (as with verroah virus in bees) that line has to be moved, to take account of the onward march of a diseased population, unable to comply with political directives.

Mr. Cohen also pointed out the Krebs 'control', for many reasons was weak, a point with which we agree. And the point of both quotes was for the writers to question why the methodology of the RBCT was watered down from that which had been sold to participating landowners at its inception meetings.

Many have commented of the trial, that "it told us nothing we didn't know before". So one has to question why that knowledge of peturbation, badger ecology and everything else painstakingly gathered over 30 years was not used and acted upon.

Anonymous said...

matthew 6.50 said "When we post letters and comments from other sources, we cannot, nor will not attempt to answer for their writers.". However, in your original post, at the end of the quote from Cohen you say "..with which we fully agree", either you've agreed with something that you don't actually agree with (or don't understand) or you do understand it and can answer the question from anonymous 9.58am - if the proactive and reactive arms were supposedly so similar, why did their results differ so greatly?

Matthew said...

Anon 10.36
We said;
"We cannot speak for Mr. Cohen, but from personal experience of the RBCT, if the 'cull all badgers' methodology had been carried out effectively, then the results should have been similar"

Similar as in the sentinel cattle tests should have shown similar results. As the methodology of the RBCT was so compromised, neither area gave the results of previous policies or trials for reasons well described on this site by those involved with both, which was to be expected.

Anonymous said...

So far as I can see from this thread, the prevailing logic (if one can call it that) seems to be: some people say the RBCT was compromised, therefore it must be, and therefore it is possible to claim absolutely anything with no need for evidence or consistency. You either agree with cohen, or you don't. You have claimed to do both.

This is clearly no sort of useful forum for debate, when one side insists on such shoddy standards. Whatever criticisms can be levelled at the ISG the scientists involved can construct a coherent argument. Which is more than can be said for the majority of traffic on this blog criticising them.

Anonymous said...

Anon 4.02 (the third response on this page) raises the good point that Cohen has said there was no control when there clearly was (in fact it was one of Krebs' recommendations). It is very difficult to conduct a trial completely without flaw but the important point is: do the flaws make any difference to the conclusions? Now I think Cohen's point about the control was that it wasn't a perfect control because some farmers were illegally culling. Now if they were then this would have been very piecemeal and would have produced an overall increase in incidence (from the perturbation effect). By comparing the BENEFICIAL proactive effect with an actual DETRIMENTAL effect in the control areas, we are in fact INCREASING the apparent beneficial effect in the proactive areas. So if the controls were imperfect for this reason, this would imply that perfect controls would have shown a even smaller beneficial effect in the proactive area, supporting the proposition that culling is unlikely to help overall.

I also have to agree with anon 9.31, many of the arguments put forward by the matthews lack logic. Also interesting that Cohen claims that "the conclusions drawn can be challenged by a competent sixth former". One of the good things about the peer review journal system is that, not only do papers get peer reviewed prior to publication (and not by the authors themselves as you've claimed at least twice on this blog) but once a paper has been published, many journals are very happy to publish criticisms and the exchanges that follow. If you have genuine arguments against what happened in this trial (and can manage to put your points coherently), Nature (for example) would be very happy to hear them. They would then send them to the authors (i.e. the ISG) and the debate could be had in public in the pages of Nature. People who do this are more likely to be taken seriously than those who grab at anything that says what they want to hear and put it on a blog as though it is fact.

Matthew said...

To the last Anons.
We started this site with our experiences as cattle farmers of extensive Tb breakdowns, and in many cases, no bought in cattle.. End of.

Four of us have been involved in the RBCT and have similar stories.
As you quite rightly say "we are nobodies" - just cattle farmers.
However that does not negate our observations of Krebs' protocol, of RBCT methodology or its chaotic and entrely predictable results, but it does preclude the editors of Nature, Science, Vet times etc., from publishing.

Our experience of the RBCT is now mirrored in statements to EFRAcom from wildlife team mangers (Paul Caruana) vets and ex SVS personnel and comments on this site from WLU operatives which we are happy to post. That the RBCT dossier has passed into the realms of 'science' is a matter of speculation as the true meaning of the word, as Dr. Gallagher pointed out in his 'Opinion' piece.

The point of this thread was to muse on the way badger epidemiology and social group habits already researched and published, were so disregarded by the ISG as to make such a predictable result of the RBCT.
And for that we may have to revisit the very beginnings in 1997, when Bourne told a practising veterinarian that 'No way was Government going to cull any badgers, so the trial would centre around cattle to cattle transmission'. In 1997, before it started?

And cattle/cattle is what the RBCT report has centred on. But with the greatest of respect to Professor Bourne et al, it does not answer our questions as to where did pernicious and persistant Tb infection in our herds come from, if no bought in cattle are involved? And if the other side of that know and acknowledged Tb reservoir is not removed, how on earth do we get the cattle clear?

But Dr. Cheeseman has already answered that, and Bourne's report sneaks it in. You get rid of your cattle.

That doesn't help the badgers and will not prevent the inevitable spillover into other mammalian species - a situation already on the rise and documented in cats, camelids, pigs, sheep and dogs.

The other uncomfortable (from the point of view of Defra) consequence of this prevarication, are the high profile challenges of people who farm a few Dexters or companion cattle, often organically, and are not prepared to conform to a rigid Tb protocol of killing them out, only to be reinfected by an untouchable source.

Anonymous said...

I have not read anywhere on this site anyone saying that you are nobodies - that would be a ridiculous thing to say, the whole point of this is to reduce the breakdowns and help the farmers!!

Second point, you said "it does not answer our questions as to where did pernicious and persistant Tb infection in our herds come from, if no bought in cattle are involved?" - stop implying that the ISG have denied that infection comes from badgers, of course they don't, their results clearly show that it does but that culling won't work (and don't bother with the old 'but they didn't do it right' - methods have to be proven to work before they will be implemented as national policy so anything you propose is still just speculation).

Third point is, being farmers does not preclude you from having your opinions voiced in Nature or any other journal, that's not a valid reason for not using that route. It's a rather more professional method of getting what you want then petty digs at respected scientists on a blog where you know you have an audience of farmers keen to hear *your* spin.

Matthew said...

Anon: 11.31
Re 'nobodies'. Some comments have implied far worse. You are quite correct to say the whole point of 'this' is to "reduce the breakdowns and help the farmers"

But would that 'this' be the ISG report, or the information - particularly PQ's - archived on the site + our own experiences of biosecurity in action?

Yes, you are quite correct. The one thing the ISG has confirmed is that some "infection comes from badgers". Up to 95 per cent the CVO said in the 1995 report. Of course a cow carrying Tb is not going to have a miraculous cure when she enters a cattle lorry, and farmers have a responsibilty in that direction too.

Your next comment we aren't clear on - except that we shouldn't repeat that the way the ISG carried out 'their' cull was not executed in a manner likely to obtain optimum results.
".. culling won't work (and don't bother with the old 'but they didn't do it right' - methods have to be proven to work before they will be implemented as national policy so anything you propose is still just speculation).

If we feel that badger social behaviour and the experience of those involved in the trapping, was ignored, thus giving a predictable result, then we reserve the right to say so. We've been saying it since 1997.

We do not accept that walking away from this will any way make it better, either for cattle farmers attempting biosecurity measures which Defra admit will not protect their cattle, or for badgers in whose groups this filthy disease is being allowed to fester.

We favour a targetted type of 'clean ring' cull of badgers implicated in cattle breakdowns, as described by Andrew Proud, BVetSc, MRCVS and exDVM in a previous posting. This to be brought up to date using gamma interferon bloods to check badger health as the ring moves out, and careful oral vaccination of healthy badgers to prevent them contracting latent diease as they move inwards. Probably an infected sett would benefit from destruction too, as infection is known to lurk for up to 2 years.
The intradermal cattle skin test we are happy with - having been on the receiving end of so many. And with no wildlife reservoir, test and slaughter of any cattle reactors has worked elsewhere extremely successfully.

Any tag-ons to cattle testing will not have the slightest effect on herds like those of contributers to this site, unless and until the wildlife reservoir is tackled. Most of the ISG recommendations have been tried before. They have failed - more on that later this week.

Editors are responsible for their publication's output. If media was unbiased or it was easy to get lay ideas published, then blogs such as this and that of our senior partner, would not exist.

Matthew said...

Correction - typo.
"95 per cent of herd breakdowns attributed to badgers in CVO's 1995 report" should read 90 per cent.

Jim said...

Matthews all - I'm not sure where all these Anon.'s are coming from, but I just wanted to say as a farmer that we owe you a large debt of gratitude for this site, and for bringing some clarity to the debate (as opposed to the spin and disinformation that emanates from some quarters). I'm still ploughing my way through the ISG report, armed only with a calculator and a maths O level, and hoping that I'm the sort of "scientifically-informed individual" whom Prof Bourne rather loftily referred to on Farming Today last Saturday. If not, then apparently I won't be able to understand it, so presumably will be expected to submit meekly to the same sort of mathematically-modelled culling which FMD witnessed (and which has been comprehensively debunked since). What I do understand very clearly is that the way the RBCT culling of badgers was carried out was worse than useless so, even though the ISG's sums may all add up, the premise on which they are based is false - so the ISG's conclusions tell us nothing of any value. I don't see why I have to be a Prof before I'm allowed to say that. It was interesting to hear Prof Woodroffe getting so defensive when challenged by John Gallagher on the same Farming Today programme, incidentally. Sorry for the rant but it seems some people in their ivory towers have no idea what this problem is like on the ground.

Matthew said...

Jim, your overview:
".. even though the ISG's sums may all add up, the premise on which they are based is false - so the ISG's conclusions tell us nothing of any value"

is exactly what we've been trying to say. We have heard it called 'torturing' data.
With thanks.
Matt 1 & 3

Anonymous said...

and how is ranting incoherently on a blog going to help the situation? don't you think there just might be better ways of helping yourselves??

Anonymous said...

"So far as I can see from this thread, the prevailing logic (if one can call it that) seems to be: some people say the RBCT was compromised, therefore it must be, and therefore it is possible to claim absolutely anything with no need for evidence or consistency.....

This is clearly no sort of useful forum for debate, when one side insists on such shoddy standards. Whatever criticisms can be levelled at the ISG the scientists involved can construct a coherent argument. Which is more than can be said for the majority of traffic on this blog criticising them."

Couldn't agree more.Particularly when so many of the matthews, jos etc.are so obviously ignorant of some of the most basic facts about badgers.

And how's this for a parliamentary question/answer?
"80% of bTB transmission is cattle to cattle" (Ben Bradshaw)

Amazing how those PQs can elicit info that certain parties would rather not publicise isn't it? Or perhaps you feel that this was inaccurate whereas all the ones you use are perfectly reliable ?

George said...

Well said Jim.

Never forget that mathematical models are only as good as the assumptions they are based on.
Since there are a very large numbers of variables affecting this disease, some of which are probably unknown at present, this makes accurate model building very difficult.
Statistical analysis is pretty tricky too, for the same reason. Especially if they are based on dodgy estimates.

Incidentally, contributions to a blog like this, particularly at present, could be very important. You never know who is reading it.
Obvioulsy you did...

Anonymous said...

Perhaps it is helpful to include the whole "80%" statement

Mr. Drew: To ask the Secretary of State for Environment, Food and Rural Affairs what the incidence of bovine TB caused by cattle-to-cattle transmission was in the latest period for which figures are available. [33813]

Mr. Bradshaw: The evidence in this area is complex. It is difficult to pinpoint sources of infection for individual herd breakdowns, particularly when infection by wildlife is a possibility, and the regional variation in the incidence of the disease complicates the overall picture. It is, therefore, not possible to put a precise figure on the number of cases of bovine TB (bTB) that can be attributed to cattle-to-cattle transmission (or to any other source of infection). It is clear, however, that "cattle-to-cattle transmission is of critical importance" (Independent Scientific Group on cattle TB, 3rd report, p41) and in low bTB incidence areas there is evidence that it could be responsible for around 80 per cent. or more of cases.

The evidence from work recently submitted for publication does suggest that cattle-to-cattle transmission is the main cause of TB spread in areas currently free, or relatively free, of cattle TB.

But the situation is quite different in the high incidence areas of the country where 85 to 90 per cent. of all confirmed breakdowns occur. Some herds in these areas are also infected by purchased cattle, but wildlife is a major source of new herd infection and in some counties it may be a more important source than cattle.

12 Dec 2005 : Column 1591W

Jo said...

'Whatever criticisms can be levelled at the ISG the scientists involved can construct a coherent argument.' says one of your anonymous contributors. I beg to differ. It is their lack of a coherent argument that has most surprised me.

To quote F J Bourne:
'Scientific findings indicate that the rising incidence of disease can be reversed and geographical spread contained, by the rigid application of cattle-based control measures alone.) (ref. his letter to Miliband).

‘The ISG also conclude that rigidly applied control measures targeted at cattle can reverse the rising incidence of disease, and halt its geographical spread……….Having shown that the main approach to cattle TB control should be rigorously targeted to cattle, we hope that the overwhelming scientific evidence we have provided to support this view……..’(ref. the ISG press release of 18th June 2007.)

‘Our modelling work indicates that implementation of cattle control measures outlined in this report are, in the absence of badger culling, likely to reverse the increasing trend in cattle disease incidence that has been a feature in GB for decades. It is also possible that more effective cattle controls will lead to a decline of the disease in badgers, although the timescale for this is likely to be slow.’ (ref. Chairman’s overview, section 12.)

‘ Analysis of a simple mathematical model suggests that rigorously enforced movement testing would halt the epidemic and indeed produce some steady decline in incidence…..’(ref. Recommendations and Conclusions. Section 31.)

I read all the above before reading the main body of the report. I admit, I was surprised at these conclusions, but I read the report with an open mind, ready to be reluctantly convinced. What I wasn’t expecting was such a lack of scientific rigour in the arguments. A full analysis is not possible here, so I will concentrate on the mathematical modelling that seems to be the basis of the ISG’s ‘overwhelming scientific evidence’

‘7.24 The effect of changes cannot be assessed directly from available data but simple mathematical models, combined with the large amount of data now assembled, do allow some very tentative predictions. The infection rate concerns all sources of infection for cattle, local infection for example across farm boundaries, infection from animals bought, in particular but not only, from high incidence areas, and infection from wildlife, especially badgers. All these are important but their relative importance, and that of cattle-to-badger transmission, cannot be estimated directly’ (my bold and underscoring).
So far, so good. The predictions are tentative, indeed, very tentative, and the relative importance of the most important data is unknown. So what scientific or even logical explanation can there be for the next sentence? ’In the following calculations we assume all three sources to be roughly equally important.’
If there is available evidence to show that that assumption is a reasonable one what is it? We know that Bourne does not believe there to be such a thing as a closed herd ‘People claim to have a closed herd, but they simply do not exist’ (Bovine TB seminar for MPs September 14th 2004). There is overwhelming evidence that closed herds do exist, so there is one piece of evidence that he is not taking into account at all.
From section 7.19 there is some discussion of the mathematical model , and towards the end of that section the report says:
7.29 These conclusions are subject to substantial uncertainty and should be taken as broad guidance only.

That is the conclusion I would expect a reputable scientist to come to. There are too many uncertainties and unknowns, and the model is too simple. Substantial uncertainty is not overwhelming scientific evidence. As Kitching et al say (Use and abuse of mathematical models: …..Rev.sci.tech.Off.int.Epiz.2006.25910, 000-000) ‘It is not necessary to be mathematically literate to appreciate that no model will produce the right output when fed the wrong input. In the future, care should be taken to ensure that lessons are learned – a bad model is like a bad x-ray because it invariably results in erroneous conclusions and a wrong course of action.’ (Incidentally, I would very much recommend reading the whole article. There is much more that is very relevant.)

So where does this come from? ‘Analysis of a simple mathematical model suggests that rigorously enforced movement testing would halt the epidemic and indeed produce some steady decline in incidence…..’(ref. Recommendations and Conclusions. Section 31).

There is much more in the report to criticise, on similar grounds of inconsistency, and I will be writing to Mr Miliband (or to his successor, if he is no longer the relevant Secretary of State next week).

Jo said...

I wrote the above in 'word' and find bold and underscored does not work on this blog.
I also forgot to give the web link to Kitching et al. It is at http://www.oie.int/eng/publicat/RT/2501/PDF/23-kitching293-311.pdf

The full title is 'Use and abuse of mathematical models: an illstration from the 2001 foot and mouth disease epidemic in the United Kingdom'. Christl Donnelly, vice-chairman of the ISG, worked on the mathematical model for FMD.

Matthew said...

Anon:12.44
Many thanks for the insight and context of the 80 per cent quote.

George; Agree.

Jo. We'll post that link later. Thanks