Sunday, July 20, 2014

An epitaph to the demise of common sense.

From today's Sunday Telegraph - [link] a thoughtful piece from Owen Paterson, the former Secretary of State at Defra, whose 538 parliamentary questions on 'bovine' TB posed a decade ago, form the basis of this blog.
"I leave this post with great misgivings about the power and irresponsibility of – to coin a phrase – the Green Blob.
By this I mean the mutually supportive network of environmental pressure groups, renewable energy companies and some public officials who keep each other well supplied with lavish funds, scare stories and green tape.
This tangled triangle of unelected busybodies claims to have the interests of the planet and the countryside at heart, but it is increasingly clear that it is focusing on the wrong issues and doing real harm while profiting handsomely."
We described much the same situation, in this post - [link] and this one, earlier this year - [link] as Defra's various quangoes accompanied by Queen May's guitar, circled for the kill.

Thanks for trying Owen, we wish you well.

Sadly, the winner of this particular battle is not David Cameron, but zoonotic Tuberculosis. And in time, that pyrrhic 'victory' will affect us all.

Photo from Sunday Telegraph article : origin AFP and The Farming Forum - [link]

Monday, July 14, 2014

From Russia with love - the saga continues.

The saga of Russia's sabre rattling allegedly because of levels of TB in cattle, continued today as the Irish Independent - [link] reports a ban from Russia on imports of beef offal:
"Suspected traces of Tuberculosis (TB) prompted Russia to impose the highly damaging blanket ban on imports of beef offal from Ireland, the Irish Independent has learned.

The discovery of characteristics of the disease is understood to have alarmed Russian authorities who have cut off the supply of offal from Irish factories.

Officials from the Department of Agriculture are now involved in negotiations aimed at getting the ban lifted.

The sanction was imposed last month following a series of visits from Russian vets to 12 food processing facilities in Ireland."
This is not the first time that Russia has rattled Ireland's cage about high levels of the disease in its cattle population: in 2004 - [link] together with Poland and the UK, The Russian sabre was raised and threats issued. And so serious was this, that the European Commission drew up an inter-community Veterinary certificate - [link] which, if implemented, was another Beef Ban.
And just because that certificate has disappeared into the labyrinth of Defra's website archive, it doesn't mean it isn't lurking in a European drawer, just waiting to be signed. And we have it.

Other postings in 2004 described the process - [link] which led up to this situation, and the frantic diplomatic cartwheels -[link] executed to avoid it. Anything really, except control of the problem in the first place.

When we were reporting this in 2004, with around 5,200 herds under restriction during the reporting period, ( 5.6 percent of the 93,489 herds registered) the UK had half the levels of TB in its cattle, which we now enjoy. And still the mandarins were blissfully unaware of the possible cascade effect - [link] of a possible ban on UK beef products.

 Roll forward ten long and, frustrating years and what have we achieved? The roll out of the new computer system (SAM) no longer gives the number of herds registered, together with the number of herds having TB problems, preferring to concentrate on new outbreaks - a substantially lower figure.

But in 2011, the number of registered herds in GB had fallen to 80,454 and of those, the number with a restriction due a 'TB incident' was 8,108. So 10.07 per cent - or almost double the figure ten years ago.

As the polemic deepens with an unhealthy concentration on cattle votes v. badger votes, and tuberculosis the disease is all but forgotten, just how long can GB keep shoving this particular problem under a diplomatic carpet?

Sunday, July 06, 2014

Figures can Lie and Liars can figure....

A swift response to the recent Cull the Cows - [link] computer generated guff, came on Thursday from farming Minister, George Eustice. Speaking at he Livestock Event, and interviewed for BBC's Farming Today - [link] programme, the Minister was pretty scathing about the modeler's efforts.

Co author, Dr. Ellen Brooks-Pollock of Cambridge University described how the team had entered data into their model of potential TB bacterial transmission of:
Cattle to cattle infection, Cattle infections into to the environment and Cattle movements.
Which is pretty amazing when you realise that up to 52 per cent of badgers in areas of endemic zTuberculosis are carrying this disease. But we digress....

 Dr. Brooks-Pollock went on to explain that her work centred around 'idealised control measures'. Not if you're a cow about going to be shot on the back of a University's half baked theory it isn't: that's not 'idealised' at all. It's terminal.

But George Eustice was having none of it. He pointed out that despite epidemiological evidence to the contrary, the model had ignored badgers completely, focusing on cattle and making many false assumptions. Including one that the disease dies out naturally in the environment in 34 days.
For the pedants, badgers can sustain this disease, maintain body weight, breed and rear cubs for up to 8 years. Reactor cattle are shot - which Dr. Brooks-Pollock had in fact noticed, pointing out that 90 per cent of 'infected farms' posed no risk whatsoever. Quite correct. They are locked down, facing daily [in some cases] visits from infected wildlife and tests every 60 days with anything reacting to such 'visits' slaughtered.

Mr. Eustice stressed that computer models were only as good as the assumptions entered into them, and if those assumptions were wrong (as in this case) then the results were flawed. He also pointed out that a team of experienced Defra vets, and the Chief Scientist - [link] were exposing these flaws and that although the aim of this model was laudable, its assumptions were wrong.

 We can't take credit for the title of this posting: it appeared here - [link] with another succinct quote:
 'correlation does not imply causation'. 

Thursday, July 03, 2014

Cull the Cattle - Simples

Once again we can thank mathematical modelers for some hair raising conclusions - [link] obtained from the latest load of guff data entered, together with a generous sprinkling of mathematical symbols, into their new toy. The Guardian -[link] gleefully explores the story with the headline, Mass Cull of Cattle is required to control TB.

That sort of carnage was tried in 2001 for FMD, again using a rampant computer model if we remember correctly - but let that pass.

And we do not propose to remind readers of past efforts - [link] to control zTB with cattle controls alone. Or the effect on the incidence cattle disease if the maintenance reservoir -[link] of disease is removed. Or even the amount of bacterial contamination a single badger - [link] can generate, and how little of that 'contamination' is required to provoke a skin test reaction in cattle.

 Having relied so much on the 'rough assumptions' contained in models developed by the ISG, we won't remind the authors of this work -[link] which cost an eye watering £2.8 million, but failed to get any samples from salami sliced reactor cattle to provide evidence of onwards transmission of zTB.

And we will we do no more with this paper than point to this paragraph which describes its data input - or lack of it.
The role of badgers in the maintenance and spread of bovine TB is a matter of considerable scientific, political and public interest5, 25, 26. Owing to the absence of necessary spatial and population level data on badgers, our model does not explicitly include their role in transmission. The environmental reservoirs play a comparable function, although the contribution of reservoir species and contaminated pasture cannot be separated. The environment is essential in maintaining local infection and may be implicated in up to 80% of all herd breakdowns (Fig. 2b, green hashed area).
We have no computer model set up to ignore badgers, so we will stick to the basics.  Not of mathematical models, but epidemiology and disease control.

No disease control program in a target species can be successful if a maintenance reservoir in an interacting species is left to re infect. That is indisputable. Just as the self sustaining nature of zTB in the badger is indisputable. And ignoring it does not make it disappear.

Friday, June 20, 2014

Con tosh

From the Conservative home webpage - [link] comes a rather spiteful  and loaded piece which implies that farmers want to kill badgers for fun. And because (allegedly) AHVLA's newly published partial statistics show an apparent drop in incidence, then there is really no need to as cattle controls (many yet to hit the farmers concerned) are obviously working.

 Without going too deeply into the minutiae of SAM, the new computer system which is supposed to calculate these things, suffice to say his data are not comparable with the figures of old. Neither is it reliable.

New herd breakdowns are important and for sure, figures for those were the ones which Defra lobbed periodically into Brussels. But they hid the rump of registered herds stubbornly under restriction with zTB outbreaks, which testing cattle and killing reactors failed to clear. And that was far, far higher. In fact the last time those figures were available, over 10 per cent of GB's herds had experienced TB restriction in the reporting period.

Thus the difference between cleaning up an epidemic in a single species and eradicating it in more than one is quite simple.  If you shoot one and not the other, eradication will not happen.

That is the difference between 'incidence' and 'prevalence' of disease.
 Figures for zTuberculosis can be argued ad infinitum, with each side wheeling out an 'expert' complete with his mathematical model and predictably  conflicting view. But published data, based on actual AHVLA risk assessments - [link] put TB outbreaks attributed to badgers in area of 'endemic' TB at around 80 per cent.

So read and learn Tory toddlers at ConHome. If every cow in GB was placed in a hermetically sealed box for the duration, the disease hosted by badgers would continue to upspill into other mammals, and from them to their owners -[link] and vets. As it has started to do already. - [link]

And no amount of 'managing' statistics - [link] rather than the disease, a Grade 3 zoonotic pathogen which governments have a statutory duty to eradicate, will alter that.

Tuesday, June 03, 2014

As easy as ABC?

We have long held the view that any sort of zoning - [link] or 'risk based trading' of cattle would be bureaucratic, divisive and always running behind the problem - especially if you were unlucky enough to farm in a 'dirty' area.

That's 'dirty' as in rampant with infected wildlife, which Defra would rather not touch with a very long pole, rather than anything whatsoever to do with cattle.

But having carved the country up into dirty, High risk, Edge and clean  Low risk areas - rather too late for some areas, it seems - [link] - we wondered if an animal based certification scheme for the whole country may not be a more workable idea.

In another life, and contributing greatly to MAFF staff pensions, many of us joined the voluntary EBL (Enzootic Bovine Leukosis) eradication scheme. The country eventually became EBL free so these schemes were no longer needed, but the way they worked was to issue the farm with a certificate of compliance which accompanied any cattle sold.

 The certificate was an official State Veterinary Service document, having the farm name and holding number on the top and then a gap for animal details.. Any animal sold from the farm was accompanied by a copy of this document, and to keep its EBL status, wherever it was, it had to be retested by the date on the paperwork which is this case was three years from it's clear blood test. In effect an MOT for cattle.

 So, would this work for TB?

The result of the last TB test is important, but the due date of the next one is crucial.

 Rather than divide up historically affected areas, assuming but not really sure that 4 year testing areas are clear of the disease, why not issue an Animal Based Certification of TB testing after a clear test, with the date of the next due test on the paperwork?

This would not penalise or stigmatise any farm unlucky enough to have experienced a breakdown, but would ensure that cattle traded into 4 year testing areas were tested on the consigning farm's regime, at least once. It would also be a reminder to people buying from farms in these so called 'clean' areas, who may be  dispersing cattle just before a herd test is due.

 The 'due date' could be flexible enough to include the animal at a routine test - within reason. But should farmers not comply with this requirement to test, then if the animal concerned was subsequently found to be a reactor, compensation could be affected.
(Steers due for slaughter could be exempt as abattoir surveillance would pick up any problems. )


Tuesday, May 27, 2014

Predictable, inevitable and avoidable.

Norway is said to have been TB free in its cattle since 1963.

 The last confirmed case of 'bovine' tuberculosis was in 1986, when the disease was found in a dog.

 That is until now, when Internet site The Cattle Site -[link] report an outbreak thought to originate in alpacas imported from England.

"A shipment of British Alpacas is behind a rise in bovine tuberculosis in Norway.

Bovine tuberculosis (TB) has been spreading through Norwegian alpaca herds following the arrival of 28 Alpacas from southern England, the Norwegian Veterinary Institute has announced.

Twelve Alpaca herds are now infected with bovine TB after the batch reached Norway in the autumn.

Prior to this, Norway had been TB-free since 1986."
The Norwegian Veterinary Institute reported the 'problem' on 22nd May - [link] with added information that the animals were being subject to further serological testing after failing skin tests. Direct translation thus:

In a importisolat for alpaca in Eastern Norway is suspected of storfetuberkulose. There are positive reactions on skin test (intrakutantest) as well as complementary serological tests on several animals that are the background for suspicion.

28 Animals were imported to the appropriate isolatet from Southern England in autumn 2013.

In England is a comprehensive tuberkuloseepidemi on herds.

In addition is detected at the dozens of nysmittede alpakkabesetninger annually.

It has not been demonstrated storfetuberkulose in Norway since 1986.

This translation implies that this consignment of British alpacas at least, is held in quarantine after positive skin tests and pending further serological testing. The comment also points out that England has a comprehrensive 'tuberculosis epidemic' and detects dozens of infected alpaca herds annually.

Norway has been officially TB free since 1986. More on this, as and when we receive it.

And we won't say "we told you so".

Yes we will.