Thursday 24 June 2010

TB Update in BAS mag

You may not all receive the BAS magazine so here is the article that Dianne Summers had published.

TB Update – A growing problem

Prior to Jan 1st 2008 there were only 3 reported cases of TB in camelids in the British Isles and one in the Republic of Ireland.

When I myself came down to Tb in my herd in Sept 08 there was virtually no information available anywhere on the subject of Tb in camelids.

In June 09 at a meeting organized by Bas – I met 5 other Bas members
Also under restriction to tB. It was at this point I formed the tb Support Group. So in June last year the tb Support group consisted of just 6 people – one year later it now has 28. 18 of which are currently under restriction and 10 been through testing and now clear.

The support group gathers data on loses - skin test results – blood tests results – side effects – watch group etc and this data has helped others make decisions in how they manage their herds and deal with tb but also the data has made members aware of the situation and how serious it is.

I am pleased that my name and the TB Support Group is now added onto the AH/DEFRA letter of consent to test. The letter of consent is the document given to new herds that have the misfortune to come down to TB. A document they must sign when they agree to test. I am thankful to AH/DEFRA for this and proves not only that we are working together but also they recognize the TB Support Group as invaluable help for fellow camelid sufferers. The Support group has a direct line of communication with DEFRA/AH HQ and any problems that arise can be dealt with swiftly and this is a line of communication we appreciate.


Ricardo de La Rua-Domenech of the bovine tuberculosis programme from DEFRA kindly informed me that as of the end of May 2010 there are approx 30 alpaca herds currently under restriction and that we have had 8 new breakdowns so far in 2010. 3 of the 8 new breakdowns in 2010 have be linked epidemiology through alpaca movements or purchase.


THE Following DATA IS FROM 18 HERDS THAT ARE currently under restriction and IN CONTACT WITH THE TB SUPPORT GROUP. I have no data on the other 12 currently under restriction.


Up to Dec 31st 2009 those in contact with the TB support group lost 144 alpacas/llamas confirmed TB. This works out roughly 12 a month. From that 144 we had 12 skin test positives 7 of which were from one herd.

In the first 4 months of 2010 from 1st Jan - 30th April 2010 members in contact with the TB support group have lost:

94 alpacas.
9 of which were skin test positives
48 were Rapid/Gamma blood test positives All of which passed the skin test.
37 sudden death or euthanized due to clinical signs

94 losses in 4 months = 23.5 per month so double the quarterly ratio of last year.

Again this is only from data provided from herds in contact with the TB support group.

We all know the skin test isn't removing infected animals from the herds with the exception of a low number of skin test positives but the blood tests are. This is why the gamma interferon validation project on Tb free areas is vital and we have now reached our target of 300 required and we have a lot to thank BAS Mike Birch for his constant hard work and the herds who have kindly offered up their alpacas for testing - the alpaca industry have an awful lot to thank you both for. Once/If validated we may be on our way to a reliable ante mortem test but this of course depends on the findings from the trials. Lets all keep our fingers crossed. It is working well on herds with breakdowns but it needs to work well on those not in a breakdown. We all know specificity v sensitivity and the importance of both.

DATA ON BLOOD TESTS
From Nov 2009 - March 31st the Gamma Interferon blood test has been used on 4 herds in the TB Support Group and has picked up 50 TB infected alpacas from 155 alpacas tested in just 4 months on 4 herds. All these passed the skin test.

3 other herds in the TB support group have had both the rapid and gamma blood tests done on their entire herds in May so their data and results are not included in this update. However the Gamma is picking up far more infected alpacas than the rapid.

We all have to thank the kind members of the TB Support Group who have submitted their data to me. Thanks to them we have this data and thanks to them this data has driven the gamma validation project along.

We need to be able to come out of restriction and trade with confidence – we cannot do that on the skin test alone – the data in this letter proves that.


We all need to be responsible – we all need to do our homework. We all need to take this issue seriously.
The new bAs Code of conduct and bio security guidelines and self declaration forms need to be used. They are there to protect you.
All are available on the bAs website.

Lastly if you are not in the Tb Support group then please contact us – we need to work together. Don’t go through it alone. The Support group not only provides emotional support but valuable information which you will need. We also need your data.

To keep up to date with the current Tb Situation I highly recommend you regularly look on the following blogs.
www.tbinalpacas.blogspot.com and www.bovinetb.blogspot.com

Dianne Summers Camelid TB Support Group summersdianne@yahoo.com 01209 822422

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