Thursday, January 26, 2006

A Voice of Sanity in a Mad World..

Yesterday the ISG (Independent (but they are not) Scientific (debatable) Group (no conflict there) gathered in London to present the latest update on the RBCT 'Krebs' trial. A voice of sanity they are not. For that please see later in this post.

At the ISG jolly, Professor John Bourne outlined his victims (badgers) and villains (cattle) and ensured his survival and place at the public trough Defra call the TB budget for .... as long as it takes the statisticians to numbercrunch his 'trial'. He dismissed PCR technology, (well there's a surprise) and outlined improvements to the Gamma Interferon blood test which allegedly has been 'refined' to exclude at least some of the false positives. However under OIE and EU inter trade disease monitoring the skin test is supreme. Anything else is supplementary to it.

It was only 3 years ago, when a leading light at VLA (Veterinary Laboratories Agency) told a contributer to this site, 'Don't go there, you'll lose half your herd!'. the Gamma Interferon blood test measures antibodies to a challenge from m.bovis in the bloodstream of the candidate animal. So if a cow has had exposure - and her immune system has fought it off, the gamma interferon bloods would identify her as a positive when in fact, in another world, she may be classed as 'vaccinated'.

Dr. Rosie Woodruffe described how she assessed the numbers of badgers around to be captured in the RBCT. She went out at night with a lamp - and counted them.

Bourne blamed the badger activists for the peturbation effect experienced in the RBCT. "They released my badgers" he explained. Well they said they would, what did he expect? And the meeting was told that a free running badger (one excluded from the social group?) at about 4/5 years old but not yet in the emaciation stage of advanced tuberculosis, was the most dangerous for onward transmission of Tb. As a 'disperser' with no social group, his range was immense and although outwardly he appeared 'healthy' in that his body weight was normal, horrendously infectious he most certainly was.

The meeting could have been described as more entertainment value than 'science', with Thornbury's 100 percent clearance of tb in cattle dismissed out of hand by Professor Bourne.

That was depressing. Predictable but still depressing. More on this can be seen at:
http://www.farmersguardian.com/story.asp?sectioncode=1&storycode=1378

This site receives several comments but one received today we felt deserved a more prominent posting and we show it below in full entitled 'A Voice of Sanity':

Sorry I have to remain anonymous, as I'm a civil servant, an officer with State Veterinary Service - MAFF/Defra/Ministry, whichever you prefer.Yes a vaccine against bTB is the ideal, but before a vaccine can be used on animals, it has to be guaranteed 100% effective. Once an animal has been vaccinated it will show as a Reactor if tested, due to the antibodies generated, the whole point of a vaccine. The BCG vaccine used in humans is less than 90% efficient. If humans get TB they will react to the Heaf test, and if a clinical case, will be treated, and usually cured, with antibiotics. Cattle aren't, why not? The extortionate cost of the drugs, plus the animal would test as a Reactor at any future tests.

The Tuberculin test is in fact, a very good test, and certainly the best we've got at present. We actually get an extremely small number of false negatives (animals that are infected with TB that don't show as Reactors) and they're usually found to have developed TB extremely badly, affected by BVD, or other conditions which damage or destroy the immune response of the animals. The fact that an animal reacts to the test, does not necessarily mean the animal is clinically infected - it has the antibodies to the disease, hence the reaction.

The fact that we don't find Visible Lesions does not mean the animal isn't infected. A bovine is a large animal to PM, and we're only allowed around 5-8 minutes for performing a PM, so the most common sites are targetted, using (palpation) manual feeling of the lungs, and knife to cut organs and lymph nodes open for examination by eye. A TB lesion in a cow can be the size of a grain of sand - using the Mark 1 eyeball - not easy to spot and easily missed. Culturing TB by VLA is to say the least rather hit and miss. An animal will react to the test if it has been exposed to TB and developed the antibodies.

By far the majority of VLs that are found are what we refer to as "closed" cases - not getting to the outside world, less than 5% (probably nearer 2%) of PM'd cattle are "open" cases, in Lungs, Kidney, Liver or Udder, where the infection can spread to the outside world and cattle to cattle, or cattle to wildlife (ie the Holstein/Friesian foxes). Cattle moving from the west country were blamed for introducing TB to Cumbria and other places post FMD, but spoligotyping (strain) of the TB showed to be different to the west country type - therefore home-grown more locally. Look at the number of closed herd animals that become Reactors. Cattle are tested so frequently that very few are badly infected with TB. Unfortunately B&W foxes are not tested...........Badgers are extremely susceptible to bTB, but don't die of it very quickly, once infected they produce huge amounts of the organism, which they spread as they move along, constantly dribbling urine as they go, and in their faeces and saliva. They gradually get sicker and sicker, eventually being forced out of their sett and have to go elsewhere.

Farmers are criticised for their lack of bio-security, yes you can keep cattle away from known badger dung pits; but you can't tell where they've been dribbling, and you certainly can't keep badgers away from cattle, and out of their housing in any practicable/affordable way. Feed and drinking troughs are an absolute Mecca for B&W foxes - who's going to refuse a free meal! Maize clamps are a huge attraction to badgers, which get driddled on and infected.

Cheeseman and Bourne have lost all credibility in my eyes. The Krebs trials - what a farce, and a misinterpretation of the scientific facts. Wildlife Unit staff in Reactive trapping areas, only allowed to put traps out for 8 days - the badgers don't get the chance to get used to the traps, so yes there's bound to be disturbance - a sett with 6 accesses would have 12 traps - badgers aren't that thick they know something's different! Many setts have many more entrances. It is not possible to trap out 100% (apart from being illegal under the Berne Convention), 50 -75% at most. Unless a sett is cleaned right out and kept completely empty for at least 3 months - probably nearer 12, the TB organism will still be present and waiting to infect any clean badgers. This is why the ring culling by gassing in the 60s/70s actually caused a decrease in TB incidence.

Where do you find TB in the human population? In heavily or over-populated housing, especially in warm damp conditions - any similarities with a badger sett are purely coincidental!SVS staff on the ground are as frustrated as the farming community - NO-ONE wants to see the badger exterminated - just a HEALTHY and CONTROLLED population, so they can exist in harmony with cattle. There is no natural predator of the badger - they top of the line - where there's a high badger population, there's very, very few hedgehogs, ground-nesting birds or hares - they live and breed above ground, and hence, are easy Take Away mobile food for badgers! Any mammal can become infected with bTB, and there's no doubt that deer population is becoming seriously infected and another reservoir of infection. Where do deer pick up the infection? The same way most cattle become infected - grazing or eating infected feed.

It is no good just taking and killing cattle, the wildlife reservoir has to be tackled. Some farmers have lost more than 50% of their stock, and in some cases the last of blood-lines that have been bred by their forefathers. Come on Bradshaw, bite the bullet (not much chance of that though) and order a proper, efficient cull of the wildlife reservoir as well as cattle - oh, but I forgot, that's not politically acceptable.

To quote the proverb, "Don't shoot the messenger".

As we have said, 'the messengers' of tuberculosis are cattle that react to the skin test, like the canary in the coal mine. But Defra appear quite happy to pile up dead cattle without listening to the song they're singing. And when herds like those belonging to 3 of our contributers to this site go down, with a confirmation from the Cattle Movement Service (BCMS) that ' No bought in cattle have entered the holding', contamination of the environment has reached a point where overspill into other species is inevitable.

5 comments:

Anonymous said...

"voice of sanity" - more like a disgruntled civil servant. If you look hard enough in any large organisation you will find someone who disagrees with the corporate line.

The disgruntled civil servant clearly isn't a vet or a scientist or anyone with any practical experience of this awful disease.

Matthew said...

I think you are wrong 'Anonymous'.

Everything the comment said was in our experience, factual and certainly not sniping from a disgruntled employee. In fact to be 'disgruntled' about a 'corporate policy', assumes that the employer had a policy in the first place, and clearly Defra do not.

You said: "The disgruntled civil servant clearly isn't a vet or a scientist or anyone with any practical experience of this awful disease."

Define practical experience.

After 5 years of continuous 60 day testing, one could say that the 'practical' side of herds under restriction, (especially herds where cattle have been specifically excluded as the source of the tb breakdown) is well covered by our farmer contributers. The epidemiological side is defended by our co-author.

But cattle postmortem details? Vaccination and the Heaf tests?
Site of cattle lesions and their relative infectivety for onward transmission?
Badger habitat and behaviour?
The weakness of Krebs protocol?

Your authors have pooled their respective knowledge of the situation on the ground backed up by Parliamentary Questions on this site, but this post contained an enormous amount of valuable information that we hadn't been aware of.

We have no idea of the author's identity, but the value of its content indicated that a deskbound theorist or disgruntled civil servant it was not. And we are most grateful for its contribution to the debate.

Anonymous said...

As somebody who has worked on various culling methods/strategies over the past 13 years or so, including the Krebs Trial,I feel qualified to add to this debate. Krebs has proven one thing, and one thing only- that there is a proven link between the spread of TB in cattle and that in badgers. If you accept the theory that the Reactive culling operations caused the perturbation(dispersal) of badgers, which made the TB situation even worse elsewhere, you have to accept that the link does indeed exist. We have over 100 staff with literally a thousand years of hands on experience between them, who have a clear view on what must happen to reduce/eradicate the disease- that is, break the cycle by slaughtering the infected cattle and do the same in the wildlife population. It might be unacceptable for the general public to accept that 1000s of badgers might die in the process, but that will have to be the bitter pill to swallow ! All of the fieldstaff working on Krebs have felt the frustrations of having to carry out their operations to a very prescriptive method. It does not allow for any common sense approach to what is often a practical problem that could be easily solved if only.......common sense could be used !!

The way forward now, is to try to get ahead of the disease. Playing catch up has never worked, due mainly to the red tape and bureaucracy attached to the policies that were in force at the time. There were/are some utterly ridiculous restrictions/limitations on what is allowed or not allowed when catching infected badgers.This has frustrated the hell out of who are/were( they are now being made redundant) very willing and able field staff.
PCR machines, on the face of it, could prove to be very usefull. Testing setts, determining the TB status of it, as a precursor to a removal licence being issued is surely an acceptable way to move forward ? If common sense is allowed to rule, we have a chance to move ahead with the battle against this disease. If we leave it to those who think they know the best way forward, we had just as well give up on the whole thing right now and allow nature to ruin the cattle industry totally. Financing trial after trial, review after ereview, is wasting valuable time. Cull infected badgers, close down their infected setts, slaughter infected cattle, use pre/post-movement testing and the answer is theer for all to see- a clear way forward that will soon produce acceptable results. Why are we waiting ??

Anonymous said...

You will all be aware that Defra has all but disbanded their Wildlife Unit. Approx One hundred operatives have taken voluntary/compulsory redundancy, with only management and Admin staff left in their present roles. With those staff departures, went any chance of the farming community fighting the TB epidemic. If anybody thinks that the farming community, as committed as they are to fighting the disease, can cope with any future culling policy, they are misled ! The only chance they had was to fight the disease using the expertise of the Wildlife Unit staff. Now they have gone, I fear that the only chance they had has gone with it. Statistics and number crunching is what you can all look forward to, with those at the top using data to prove whatever theory they are trying to push at the time. We all know what a farce Krebs was, yet we are using their data information to evolve a future policy on the eradication and control of TB. Using their data, aligned with their very biased and one eyed views, there is absolutely no chance of ever getting on top of or ahead of TB. Indeed, if my suspicions are correct, the farming community are going to be stuck with cattle based control methods with no chance of ridding the countryside of infected badgers. Unless the cycle of disease is broken, you are going to have a reservoir of infection in the countryside forever. Thsoe of us who have worked on the culling trials knew the best way forward- cull infected badgers, cull infected cattle, pre and post movement testing, improve the diagnostic tests and then the Holy Grail- vaccination(withing 15 years of course !)

As an ex-Defra employee, I have no axe to grind with the Department. They are excellent employers. My gripe is with the way the Krebs trial was executed and the subsequent dat collected and the results gathered are being used. They are not reflective of what is really happening in our countryside. Until our Minister has the courage to front this epidemic robustly, you will all have to suffer as you have done for the past 10 years. Pessimistic or realistic view ? Believe me, it is the realistic one !

Matthew said...

Unfortunately, we all agree with you here. Defra have absolutely no intention of touching this one with a ten foot pole - and that's despite (or perhaps because) of the sundry and varied little bTb hamsters, beavering away on their respective wheels. Going absolutely nowhere, but using job opportunities as they arise.
The losers are the badgers and a heap of dead cattle.