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Previous BLUETONGUE UPDATE  Feb 20th 2008

Report on the Full BTV forum meeting held this afternoon.

Intervet have sent out forms to all veterinary practices with clients in the PZs asking for firm orders for their clients, so if you have not had a form yet, and have clients who will qualify, then please contact Intervet.

Remember that only animals within a PZ can be vaccinated.

The Vector free period is being said to be unlikely to last beyond mid March, so if you are in a PZ and wish to move animals to either the SZ or a free area, or in the SZ and wish to move to the free area, it would be wise to do so NOW otherwise the window of opportunity will be lost until vaccination can take place.

Note that South East Wales is now declared to be a “Restricted area”. This is in effect a surveillance zone confluent with that in Gloucestershire and part of Herefordshire. The reason for the different name is  that there is no law in Wales enabling the Welsh assembly to declare a surveillance zone!!.  So much for home rule??!.

We now have 81 known infected premises as of today.  66  were found in 2007, of which half were found on surveillance. All 15 cases found since January 1st have been disclosed as a result of pre movement testing All have either been serologically positive or shown a weak PCR positive reaction, suggesting that infection took place before the start of the VFP. The case near Poole was a surprise development, but not a great shock, and is being further investigated. Blood and bulk milk sampling will be carried out in surrounding premises with results expected in 2 to 3 weeks.  The total number of animals tested pre movement is now over 40,000, and the pre movement testing progamme is considered to have made a major contribution to our understanding how far things have really spread.  Some of the 15 cases this year have involved several animals.  All  15 have been in cattle.

The meeting was chaired by John Kittner who declared that the very low levels of viraemia found were unlikely to be sufficient to infect midges, but that view was contested by Chris Lewis who pointed out that it is thought that the virus may overwinter in T cells and then infect midges. A recent paper has also suggested that the virus could overwinter in skin, and be undetected  by a PCR.

From August 4th, when infectious midges are thought to have crossed the channel, much of the original BTV infected area was under movement restrictions until mid September, due to FMD.  However there was a “Window of opportunity” for a week before BTV was declared to be circulating, when free movement of ruminants was possible, and  tracings of surveillance and pre movement positives are beng carried out to see if livestock from those farms had come from the original PZs.  It is an obvious concern that animals could have moved to almost anywhere in that week, and by doing so could unwittingly have spread infection which could recrudesce later this year to start off new hot spots.  That could only be detected in advance by extremely expensive, time consuming, and in effect impracticable levels of testing!!

The vaccination policy as you will know,  is to be voluntary in the UK.  The aim is to have as near 100% uptake of vaccine as possible.  In goats, that would be a problem if a seven day withdrawal period for milk were to be imposed in line with established practice where medicines are used without a specific marketing authority.  All I can say is that the GVS,  through the BVA who carry somewhat more weight if we do it jointly, are actively lobbying for the imposition of the 7 day milk withdrawal to be waived in the interests of  maximising vaccine uptake, and avoiding the possible creation of a reservoir of infection in goats somewhere or other.  It could be a while before we get an answer as it raises problems never before considered.

There was considerable discussion re the merits of a voluntary scheme as against a compulsory one.

The great argument in favour of a compulsory scheme is that it would be likely to wipe out BTV8 at a stroke,  BUT it could of course come back into the country at some time in the future.  Also in favour is the well reported EU “Co Funding”  for compulsory schemes in any country.  Against a compulsory scheme is that it would be likely to lead to INCREASED cost to the farmer.  The vaccine would be subsidised to a level which is in fact slightly LESS than DEFRA are contracted to pay for it,  and  there would be a payment of 0.15 Euro per sheep or goat, and 1 euro per bovine towards the cost of administrtaion.  That administration would have to be under veterinary supervision, which apart from that adding to the cost,  would also need some potentially expensive beaurocratic back up to prove that the job had been done correctly. Overall, the cost to the farmer would be greater according DEFRA.

It must surely be a borderline decision, but perhaps the final sway of the argument is that it would be difficult to find veterinary manpower to “Man the pumps”, and if we could as a profession cope with that, it could well be at the expense of stopping other things, such as Tb testing. That hapened in 2001 due to FMD, and led to a serious rise in the numbers of animals with TB.  It has to be a concern that  farmers will not respond to the need to vaccinate, and all were agreed that we must press farmers to vaccinate wherever possible, not just to protect themselves, but  in the wider interest.

At the same time, it was made clear that there could be problems, especially where finance was tight due to livestock having been unsaleable last Autumn due to movement restrictions, and where animals were due in the normal course of events to be moved to summer grazing in a PZ from outside, which would  create a great difficulty as they could not be vaccinated pre movement.  These concerns are recognised, but practical answers are hard to come by.

The  experience of farmers on Mainland Europe this year is that they would tell their counterparts here that vaccination is a “No Brainer”.  There will be occasions when the bank needs to be convinced, and where practicalities need another look before policy is totally finalised.

After vaccination, stock can be moved ANYWHERE within England  60 days after the the completion of  vaccination. I assume the same will apply to movements from England into Wales and Scotland, but I need to seek clarification.  Alternatively, stock can be moved on the same basis if, not less than 14 days after vaccination is complete, That is 1 dose for sheep and two for cattle, and to be decided for goats, the animals have been blood tested  with PCR negative results.

Thus there may be different tiers of certification needed by farmers.

  1. None needed,  vaccination for as it were internal use only, where stock will always remain on farm.

2.  A certificate needed to allow animals to move out of a PZ but within the UK,  probably based on prescription for or supply of, and return of empty vaccine bottles, to correspond with stock seen on inspection, by the veterinary surgeon, which will allow movement within England, and subject to confirmation, Wales and Scotland as well.

3,  for export outside the UK and probably to Northern Ireland, certification that the animals concerned were vaccinated BY A VETERINARY SURGEON.  That begs the question of whether that is JUST those animals to be exported, the cohorts of those animals, which seems to be sensible to allow for  last minute substitutions, or ALL animals on farm. Quite a        diffrent matter. This is the sort of detail whaich we all realise needs  to be addressed. 

Some of you have raised with me, the position of livestock shows.  That appears to be as I suspected, that it will depend on where zones happen to have been drawn at the time.  I realise just how difficult that will make it to organise shows. I can only suggest that the usual practice of entering livestock well in advance will have to be waived. The only people who will know where they are will be those in the PZ at the time of entry!.  That is from the showing perspective, highly unsatisfactory, but  realistically has to be the case.   The intention is to extend the PZ as vaccine becomes available to allow vaccination to take place. The PZ could also be extended, as happened twice in the last ten days to respond to a new situation.  It seems to me that show organisers might be able to negotiate with DEFRA re the timing of “Planned” extension of any PZ.  What cannot be allowed for is an extension due to spread of disease.  There is no easy answer, and whatever is done must be in the majority interest.   

  Finally, without wishing to be a prophet of total doom, BTV1 has now been disclosed near San Sebastian, Northern Spain, on the main trade route into France!.  This recent discovery really puts a different complexion on things, as from there, it is not an epidemiological longhop to the UK.

Vaccine manufacturers are being encouraged to produce a combined BTV1 and BTV8 vaccine. Indeed it is in their interests to do so.  What is more important is that  if symptoms of BTV are seen in animals that have been vaccinated, veterinary surgeons should not assume that it is some sort of vaccinal failure, but should have things fully investigated in case the strain is NOT BTV8

That really is food for thought.

The meeting went some way to clarifying matters, but detailed questioning flagged up a number of areas where practicalities need to be looked at, in particular concerning inspection of stock pre vaccination,  vaccination of stock which  might be exported to third countries, the relevant certification,  and  so on.

We seem now to have the basics in place. There are however, a number of areas where the detail needs to be made much clearer.  

I would welcome concerns that you would like to raise that have not been covered.

Nick Clayton.  

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