Sunday, November 29, 2009

A parallel?

We have mentioned PCR (Polymerase Chain Reaction) technology many times and will continue to do so. But reading again correspondence from Dr. Roger Breeze, formerly of the US Plum Island facility and a developer of PCR, rang more than a few bells.

The jobs dependent on keeping this stunning technology firmly in its box, are described by Dr. Breeze in this mail of 2007 when he was pioneering RT-PCR as a fast diagnostic tool for controlling FMD:
"FMD diagnostic technology of the late 20th century depended upon tests that involved live virus or reagents to perform the tests that were derived from live virus and thus were confined to biological safety level 3 (BSL 3) diagnostic laboratories for biological safety reasons to prevent accidental escape of live virus contaminating the reagents (no one bothered to safety test the reagents to show there was no live virus contaminant so they could be moved out of biological containment). These tests could have been moved out of BSL3 labs like Pirbright or Plum Island but there was no incentive: APHIS were the only ones who would use them in the US, they had them in BSL3 at Plum and did not want to move them out to the mainland."
There is a parallel here with the control Defra exercise over the reagent DNA assay from m.bovis which is also a Grade 3 (BSL3) pathogen. Dr. Breeze explains how PCR development was stymied by this self interest group, dedicated to blocking progress:
"The world of diagnostics was a small and traditional club in which people talked only to each other in a circle of mutual assurance and mutual congratulation. There was certainly an element of job protection in this internationally in that these were labs that governments could not easily privatize - nor could governments transfer the test reagents to private companies outside the physical limits of the BSL 3 labs. Reviews of one country's capability were performed by club members from other countries. The idea that these labs might all use the same tests and reagents prepared for the group was unthinkable.

We have heard from top officials in Defra that PCR technology 'will never be used in bTB diagnostics'. And one may be entitled to ask, why not? In whose interest is it to keep this disease circulating, its casualties increasing and becoming more varied by the day?
Dr. Breeze explains how PCR broke up 'this cosy arrangement':
Development and testing of PCR tests would not have been possible without people knowledgeable of FMD etc and with access to viruses in BSL 3 - there is clearly a continuing vital need for BSL 3 national facilities and skilled foreign animal disease scientists, it's just that the diagnostic role of central government labs has changed from test performance to quality control and quality assurance of a distributed system of laboratories that can respond very quickly.

Many FMD viruses representative of all 7 serotypes were genetically sequenced by Dan Rock's team at Plum Island and the sequence information was transmitted electronically to Tetracore in Maryland. Rock and Tetracore worked together to compare the complete sequences of many different viruses simultaneously to find regions of the sequence that were identical between all the different viruses - these common regions would be targets for PCR tests. Tetracore have some proprietary software that eases this comparison. Having identified likely targets, Tetracore made reagents to these targets and Rock tested these with real viruses at Plum Island. From this, the ARS Tetracore FMD PCR test was developed, and this did not require any materials that had ever been in contact with live viruses.."

Thus with a degree of co-operation between the people who held live assay, the PCR manufacturers enabled a PCR assay to be developed which did not depend on live components and as such was not subject to 'scientists' defending territory or playing politics.
The key factor was that electronic information was sent to Tetracore from Plum Island - this information did not require an APHIS permit. The reagents were made without BSL 3 containment off Plum Island and sent back for testing. Certainly, had it been necessary to send any piece of the virus or any reagent derived from virus to Tetracore, APHIS would have denied a permit to do this and this generation of tests would not be available today. But the computer technology of sequence and transmission over the Internet overcame the longstanding APHIS barrier ."
We have said many times and will continue to say, that this technology has more than a small place in bTB diagnostics. Whether that is to speed up positive diagnosis in cattle lesions after slaughter (as the US were doing 8 years ago), supporting positive identification of bait marked infected badger setts, or refining the blunt instruments of less than specific current diagnostic tests, ahead of slaughter.

For many of the cattle, farmed deer, alpacas and other animals now suffering continuous testing and slaughter, the wildlife reservoir now awash with infection and its inevitable spill over victims, that day cannot come a moment too soon.

Wednesday, November 25, 2009

'Our' terrier, becomes official.

In June we received a sorry tale of a little Patterdale terrier, who was found doing what terriers do and mauling an almost-dead and decidedly manky badger. This resulted in wounds to his nose and his eventual death from 'bovine' Tb. ( Please note: the Patterdale in the pic, is for illustration only, and is not the terrier in question. Patterdales are described as 'feisty and fearless' and used for 'hunting vermin'.)

Our terrier's story and that of two other dogs recently positively diagnosed with bTB, is now told by VLA staff and veterinary surgeons attending the animals, and is published in this week's Veterinary Record.
We would like to report on three recent cases of tuberculosis (TB) in dogs caused by Mycobacterium bovis, following bites from wildlife.
The most recent case concerned a healthy seven-year-old pet/working, male entire Patterdale terrier that went rabbit hunting in March 2009 in an area of Worcestershire recognised as a hot spot of bovine TB. The dog went missing and was found chewing the neck of a very thin, moribund badger. The terrier had incurred multiple bite wounds on and around its muzzle during the fight with the badger. The badger carcase was not examined. At the time the private veterinary surgeon alerted the dog's owners to the risk of TB, especially because there was a young child in the household. Antibiotics were prescribed to treat the bite wounds on the terrier's muzzle. After several weeks the dog became listless, weak and started showing respiratory signs and weight loss despite a good appetite. These clinical signs became progressively worse, and on advice from the vet the dog was euthanased in early June. Postmortem examination showed multiple granulomatous lesions in the lungs, pleura, liver, kidneys and lymph nodes.
The paper describes how cultures from affected organs were positive for SBO263 (VLA type 17) which is the predominant molecular type in the area where the terrier lived, and where the badger was found.

The second case is that of a Jack Russell terrier, who lived in inner city Glasgow and had a close encounter with a squirrel. This little chap was luckier than the Patterdale, and after treatment, has appeared to recover. The spoligotype isolated in 2008 after a biopsy on a non healing lesion, was Type SBO140 or VLA 9. Scottish VLA staff comment thus, on the strain type and their findings:
This was unexpected because the dog lived in Glasgow, an inner-city area with a very low historical incidence of bovine TB and had no reported contact with any livestock. The dog had reportedly not travelled to an area with endemic bovine TB infection. The skin lesion eventually healed and the dog returned to apparent good health
. The third case detailed in Vet. Record occurred in 2007 in Wales, where a three-year-old terrier was suspected of being bitten by a fox or badger while hunting.
He developed nodular, calcified, hugely enlarged submandibular lymph nodes. The bite wounds did not heal despite treatment. The dog was euthanased and M bovis spoligotype SB0140 (VLA type 9b) was isolated from one of the lymph nodes that showed granulomatous lesions with acid-fast bacteria.
The authors of the paper indicate that "in all three cases the local Animal Health office and local public health authorities were notified and health and safety advice was given to the dogs' owners". Although in the case of the Patterdale, we understand that this was sketchy and slow, especially as there was a child involved who had had close contact with the dog.

The authors also comment that in all three of these documented cases, there was no known contact with cattle or other livestock. And they mention increasing numbers of cats, dogs, South American camelids and goats as spill-over hosts of 'bovine' TB.

They conclude with an observation about TB in domestic pets in general, and cats in particular :
In cats, many cases of confirmed M bovis infection involve lesions in the skin or superficial lymph nodes, suggesting a cutaneous route of infection. As with these three canine cases, some of the owners of M bovis-infected cats have reported that infection followed a bite by native wildlife.
And finally, a plea to their fellow veterinarians, who may be unaware of the extent of environmental' 'bovine' TB pollution to which any mammal is suceptible:
We would like to raise awareness among small animal practitioners to include M bovis infection in the differential diagnosis of bite wounds that are unresponsive to antimicrobial treatment, develop nodular lesions and associated lymphadenopathy and/or cases of general undiagnosed malaise where there is a history of bite wounds. Undiagnosed TB in pets poses a particular zoonotic risk due to the often close contact between these animals and their owners and family.
We understand that Defra have approved this article ahead of publication. It is to be hoped that the implications set out in it, are clear to them as well.

The authors of the paper are : G.M van der Burgh,(VLA Luddington, Warwicks.,) T Crawshaw,(VLA Starcross, Devon.) A.P Foster,(VLA Shrewsbury. ) D.J.B. Denny,(B.VET.MED. MRCVS, Worcester.) and A.Shock, (VLA Lasswade,International Research Centre, Midlothian, )

Saturday, November 21, 2009

Alpacas - TB inter herd spread.

It was only a matter of time before 'bovine' TB, now entrenched in a well protected but exploding population of badgers, spilled into non-bovine species. And if our Minister for (some) Animals' Health does not turn a hair at the slaughter of thousands of cattle annually, he may just have a fight on his hands with owners of some extremely highly valued alpacas, which when they do contract TB, appear to be more than capable of spreading it between themselves.

We have returned to this subject several times since the first alert in November 2007, after a west country llama farm was decimated by disease. The case was later described in the Veterinary Record, from which we quoted in this posting. Today we received data from another alpaca stud, with a similar story to that of the Devon breeder whose females returned from stud in Sussex, carrying a Shropshire strain of TB, from which they subsequently died.

A Gloucestershire breeder has sent us the following snapshot of his experiences. His story started in early September, after visiting shows with 3 young stud males during the summer. No other disease problems were found throughout intense veterinary investigation; but within a week, three of these animals were having breathing difficulties and had measurable weight loss. Wide spectrum antibiotics failed to give results. By mid September the first casualty was euthanased and his post mortem revealed lesions on lungs and liver. Two weeks later, a second alpaca died with similar post mortem results and the third was euthanased, again with the same pm results.

The owner takes up the story:
My spoligotype has been confirmed as type 10. My Defra veterinary officer has confirmed that there have been no type 10 outbreaks near to me, which confirms their and Animal Health's initial suspicions that my herd had contracted this disease at a show. All of the three initial cases were in my junior male show team.
But as has become apparent with other cases of alpacas with bTB, inter-herd spread, often before owners have a clue what is going on, had already begun:
We lost a 40 month adult female recently (she had been in the paddock alongside the junior males for some months. As is the way with these things, she is also a show winning alpaca). I currently have three others in isolation. Two other junior males and the 12 week old cria of the dead female.
The veterinary attention these animals have been offered (banned in the case of cattle) extends to specific anti-tuberculosis drugs, used in the treatment of humans:

One of the boys appears to have responded well to Isoniazid (anti-tuberculin drug) and is back to normal weight and breathing normally. Balthazar, a multi show winning grey male, is the most recent to go into isolation and is now on Isoniazid. The drug isn't cheap but, since I was offered £8,000 for him I'm not giving up - apart from the value, I had hoped to keep him as a member of my stud team. Oriel, the cria, seems okay at the moment but, as his mother died of bTB there's a reasonable chance he could get it.

Alpaca owners have lobbed a string of correspondence in the direction of Defra's window-box over their problems with camelids. And the frustration of owners of animals infected with this devastating disease when they are met with little advice, no support and condescending pre-programmed platitudes, only increases their anger.

Like the Devon animals, (who contracted Shropshire strain 35 TB from a visiting female while in Sussex), this alpaca owner has delved into the source of his outbreak. As he points out, no alpaca has presented to VLA at this time, exhibiting Type 10 bTB. This is unlike the Devon case, where although the Shropshire female died at stud, another animal from the Shropshire farm did subsequently come within Defra's radar. He explains:
Some alpaca studs have dozens of these visiting females - so you can see the potential for spreading bTB and other diseases/parasites to the four corners of the country. As far as I have been able to find out, there is no other alpaca stud/farm with spoligotype 10 known to Defra. This makes one think that there has to be someone out there that has had animals die but, has not had any post-mortemed. Given the attitude of some of the larger commercial breeders to the bTB issue and to those of us that are making a "fuss", they probably don't want to find out as it would be too damaging to their businesses. However, if left to fester, none of them (whether currently infected herds or not) will have a business left within a couple of years.
Quite. TB in camelids is a killer, and although the intradermal skin test is regarded as the primary test for camelids, even on the recommended 'severe' interpretation, it is not doing the job. Figures of less than 20% accuracy have been bandied about and a member of the BAS board has told members that only 6 alpacas have tested positive using it. This although members of the society themselves can account for in excess of 100 animals dead from TB in the last few months.

The blood test has been flagged up as a possible ancillary ante mortem test, but veterinary practitioners experienced in the care and treatment of these animals say that interpretation of the test is not solid enough. This alpaca owner has been told that
" the only way I can be sure that my herd is free of bTB is to use the blood test, but I should be prepared to lose 4 or 5 healthy animals for every one that is genuinely infected."

He concludes: "For obvious reasons, this cannot be regarded as a satisfactory solution - especially as the Government will only pay £750 per alpaca (if they pay at all)".

This is a very sobering tale, running parallel to the experiences of many other camelid breeders across the country, and beyond. If Defra continue to bury their heads in the sand, this country runs a very real risk of establishing a second, unchecked reservoir of disease - if it hasn't done so already.

Accurate testing for any disease is vital. And if the skin test is failing camelids, and blood tests are failing them as well, why not dredge up Defra's most unfavourite toy, now widely used in the diagnostics of many other diseases in most countries - except TB in the UK of course; PCR? Just a thought....

Our grateful thanks to the owners of these beautiful animals for sharing their story - so far.....

Thursday, November 19, 2009

Protocol for Camelids - or not... ?

As we have pointed out, Defra's policy of dealing with bTB in non-bovine species is non-statutory. But with the urgency of a dormouse on vallium, Defra offer a few explanatory guidelines, which for alpaca owners and veterinary staff involved with these creatures, may have avoided some confusion.

Defra have no 'right of entry' into camelid premises so unless bTB has been confirmed, are admitted by invitation only. Movement restrictions may then be served, but protocol appears to vary depending on which civil service 'ROD', (Regional Operations Director) is reading which Defra bible and from which area. Some RODs are more equal than others, handing out instructions to highly trained veterinary staff in a fairly arbitary manner, and not necessarily agreeing with 'ROD' in the next patch. Why would they? They have territories jobs to defend. An example of this mish-mash of non-policy, is the use of the blood test on alpacas. While some RODs apparently allow just visibly unwell animals to be tested, others insist on whole herd screening. This test will never be 'validated' and its correct sensitivety / specificity established if it is directed at animals likely to be positive for bTB on ante mortem observations. Conversely, to expect alpaca owners, who regard their animals as pets, to slaughter all positives immediately is optimistic. Isolation and monitoring, combined with other antemortem screens may give a more solid picture of disease status.

Nobody wants animals with rampant tuberculosis left to fester, (except the badger groups) However the slaughter of three alpaca last week, which had been in isolation for four months found just one positive for TB on post mortem. For the other two extremely healthy animals, their cause of death could have been logged as 'gunshot wound to the head'.

Brief Defra guidelines for 'non-bovine species', have been available since early summer - at least. However they will not help the two alpaca in the photo.

Both are now dead.

Defra documents are written in civil service-ese which is neither easy to navigate, understand or interpret. Here is a taste:
10.2 As with other non-bovine species, there is at present little legislation underpinning the control of TB incidents in camelids in Great Britain, apart from the general power in the TB Orders to isolate and restrict movements of any affected and in-contact animals. There is no requirement to identify camelids or record their movements. DVMs or Local Authorities have no legal powers to enforce tuberculin testing of camelids and slaughter any reactors. Similarly, there are no provisions to compensate owners for the loss of such animals. Therefore, any testing of camelids for TB has to be voluntary, but if the owner does agree to test at the Department’s expense (see below), then this needs to be linked to a voluntary prior agreement to release for slaughter any animals identified as reactors.

Losing animals to TB is bad enough without this cat's cradle of jargon to plough through. Plain English would be good. The links for the two documents are buried contained within the AHO 'Operators Manual', and can be accessed here for Defra's Disease Reporting Procedures in non-bovine species, and the here for tuberculin testing of camelids. We note that the latter advises a 'severe interpretation' of reaction >2mm rather than the standard >4mm used for cattle, until disease is confirmed. And as with much protocol developed 'on the hoof', we understand that this too is not widely adhered to.
Or perhaps the vets doing the tests haven't read the manual either.

Wednesday, November 18, 2009

Update - 'A way forward'

In April, we introduced a film made by wildlife photographer, Chris Chapman with the overview that a form of 'management' of what has now become an endemically infected wildlife population, was a possible way forward out of the impasse that has made the UK the worst area in the world, for bTB.

This week the film was launched, and in the next few weeks it will be seen by vets and other interested parties across the country.

An introduction by Richard Gard, an agricultural journalist with an interest in animal diseases, described how after seeing a short introductory piece, all major television channels had turned down the film. Too hot to handle? The footage of emaciated badgers which had died in dire straights was not what people would have expected from the ever rattling tins of the Wildlife and Badger groups. But that is what their ultimate protection of this species has delivered. So while the carnage of FMD were brought nightly to our screens by most TV channels, the equally destructive salami sliced effects of bTB on our cattle herds and those who tend them, are ignored.

With a strap line is 'Healthy Badgers - Healthy Cattle', the fact sheet opens:
"Wildlife assessments of groups of farms with adjacent land are an important step in the control of cattle TB to operate alongside existing procedures. The project is established to offer wildlife assessments to veterinary practices and their clients for the winter of 2009/2010. No funding for assessments is currently available."
We note that last snippet.

The political slant heaped on this pernicious zoonosis is such that successive layers of Defra (formally MAFF) civil servants and their political puppet masters have sung from a different hymn sheet when dealing with the problem at the farm level as opposed to the perceived problem tossed around in the Palace of Westminister. Thus we have in place a government totally divorced from what is really happening on the farms. And the folk tending Defra's corporate window box, haven't a clue what to do. Other than kill more cattle.

The result is that cattle farms are testing and killing cattle, and then 60 days later - killing more cattle. How extraordinarily and expensively short sighted? In warfare this is known as 'cognitive dissonance', a plan of action which although destructively wrong, may work in the end because all the cattle are dead. (Or all the badgers?) But the fallout from Defra's carnage is incalculable, both on the ecology as a whole and on other species, equally susceptible to TB, as we are seeing here and here.

Mr. Chapman's film projects stoic but grim sadness from affected farmers as their animals are piled into Defra's maw, but many salient facts as well. From Dr. John Gallagher, the well made point that very small lesions in badgers will produce millions of bacteria, (with just 70 needed to produce TB in a cow - ed. [PQs]) and that from this, "it is inevitable that there will be cross contamination". Dr. Gallagher also pointed out that the disease is monitored and acted on in cattle, but ignored in wildlife.

Devon veterinary practitioner Andrew Cobner, reported a 50 percent increase in herd breakdowns in the area covered by his practice over the last few years, with continuous cattle testing and culling failing to clear problems. And several times the difference in the behaviour of excluded and extremely sick badgers, which were shown in Mr. Chapman's film, was highlighted.

And it is this 'management' of their own social groups by the badgers themselves, that is at the core of the message offered by the group promoting the film and the possible direction TB control could take, which is explained thus:
"At this time wildlife assessments are not accepted as an important part of TB control. We are convinced that a combination of wildlife assessment, veterinary involvement and cattle management can reduce the numbers of cattle being slaughtered and the number of farms under TB restrictions."
Richard Gard explained his understanding of the word 'science', which he said "involved the observation of natural phenomenon and the need to work within it". The process is ongoing he said, and once proved, the result becomes 'science'.
The core of this possible way forward uses the observed behaviour of badgers themselves, as its core. Mr. Gard described TB as the 'hidden disease of the countryside'.

He explained how farmers, their vets and maps of the farms, all formed bits of a disease 'assessment' jigsaw. Input of where cattle had contracted disease, fields, buildings or areas which were giving problems, were then examined by trained wildlife trackers and the results mapped. These maps gave a green light to setts and territories used by badgers which clear cattle tests showed were healthy and conversely, the often single hole satellite setts, used as temporary lairage by badgers excluded by the main group and which could be linked to major breakdowns, often on several farms, were marked 'red'.

In recent papers, AHO risk assessment sheets from newly infected farms, showed an overwhelming majority - up to 90 percent - of breakdowns were attributable to wildlife, and in particular to badgers. This part of the jigsaw is then ignored. It was noted that both the BVA and BCVA had mentioned 'assessment' of all available information, in relation to their client's TB breakdowns, and also 'green and red' setts, within their policy documents.

The present non-policy offered by Defra is a shambles, but anything replacing it has to tick several boxes: the main one being the word 'targeted'. This assessment of several farms within an area, using the information offered by tested cattle sentinels, and interpreted by wildlife trackers appears to us to answer that selection process.

If the badgers don't want a skanky, sick individual within their group - why would any cattle farmer?
Healthy Badgers - Healthy Cattle Project ;

1. Initial discussions between veterinary surgeon(s) and farmers take place and an assessment area of ten square miles (6-10 farms with adjacent land) is indicated to the project. An initial meeting with the project team is arranged and local practicalities discussed. Maps showing field boundaries of each farm are to be made available. an area wildlife assessment is booked and paid for (£300 per farm)

2. The wildlife assessment is carried out over several days.

3. The farmers, vets and project team meet to review findings and the TB situation [ of cattle} in the area. Actions to improve bio-security of the herds will be discussed.

Richard Gard, Andrew Cobner, Bryan Hill.

Contact : 01647 24434 or email : .

Friday, November 06, 2009

Spokes.... and wheels.

The Welsh Assembly's decision to operate a badger culling pilot trial parallel to their enhanced cattle testing programme, may be challenged by the Badger Trust. In a not unexpected hissy fit, the Trust are reported to be attempting to put a judicial spoke in the wheel of the Welsh TB eradication policy.

Badger Trust chairman David Williams said the decision would be challenged on the basis that it is not ‘underpinned by robust scientific evidence.’
We assume that he refers to the ISG's 'robust' scientific evidence rather than anything prior to 1997, or after 2007?
The charity said badgers cannot be killed unless, under the Animal Health Act, it is to ‘eliminate or substantially reduce the spread of disease’ and was ‘both necessary and the most appropriate way but without causing undue suffering’.

True. And the present unchallenged, and possibly unlawful moratorium on this part of the Protection of Badgers Act, has done nothing for the health and welfare of badgers which the Trust pretend to support, but let that pass.

Farmers Guardian has the story.

Referring to the Independent Scientific Group’s 2007 report on badger culling, the Badger Trust claimed any benefits would be ‘at best very marginal’, while the cost would be ‘substantial’. And of course in that sweeping statement, they have deliberately missed the crucial evidence given by the diminutive professor to the EFRA committee on many occasions, when he said (quite forcefully) that culling badgers "In the way in which it was done in the RBCT badger dispersal exercise", was not sustainable. And he (Bourne) stressed the importance of this, with further questioning extracting the painful implication, that a different method, on a more flexible time frame and more tightly targeted could have achieved a substantially different result.

Even the WLU operatives and managers, overseeing the diminutive professor's (political) instructions piled in with their own experiences of this 'robust' type of science.

And the Badger Trust seems to have blindsided the follow up
on the trial, completed last year by some members of the original ISG, which showed even with protocol as badly skewed as this, a drop of 60 percent in cattle TB across all the proactive cull zones, with a corresponding drop of 30 percent in the 'edge' zones was eventually achieved. But that was after Bourne published his report and so is politically and conveniently pigeon holed. Out of sight.