Thursday, July 09, 2009

Sometimes we wonder

Defra's 'Farming link' magazine arrived today and in it was a piece on their badger vaccination plans, but also an absolute gem within the piece on 'Developments in Animal Health Research'.

The former describes how this voluntary 'trial', relying on a few summer months of cage trapping (efficacy 20 - 70 per cent) and vaccinating the cage's occupant with BCG - a vaccine of uncertain efficacy, ranging from 0 - 80per cent - may damp down, over several generations, tuberculosis in badgers. Farmers were lectured on efficacy of vaccines last year for a different problem, and if memory serves us correctly, the target for a successful vaccination programme was said to be at least 80 per cent of the candidates.
Do the maths on this proposed 'trial' - and then post Defra a shiny new battery for its departmental calculator.

The latter describes VLA's spoligotyping team venturing more deeply into tracking the movement of strains of TB, and suggesting (tentatively) that this is "usually as a result of cattle movements". We would accept that statement, if other known reservoirs of this disease were not freely moved around the country with no records whatsoever of their passage, and if cattle were not pre movement tested. But it should not be a foregone conclusion with unfettered movement of translocated badgers and other species now known to be particularly susceptible to TB, and more than capable of onwards transmission, both among themselves and to human beings..

But the paragraph which had us tearing our hair was dealing with the development of badger vaccines, first injectable and then orally. But it is then noted by the commentator:
"Of course, vaccinating badgers would be unnecessary if it were possible to give calves lifelong protection against disease".

If one accepts the modelled, contradictory and topsy turvy world of the ISG who are still peddling the '70% cattle' v. 30% badgers line, one could postulate why vaccinating badgers to protect cattle is thought by VLA to be necessary at all. But let that pass... As they are beavering away to produce a BCG vaccine which may or may not work, may or may not obtain licensing and may or may not make the disease worse in endemically infected candidate badgers, what the blazes would vaccinating calves do if badgers infected with tuberculosis are to be left to fester in an environment shared with so many other mammals?

Have they not spoken to their colleagues at VLA who process the increasing number of samples from diseased alpacas, llamas, cats and dogs, more cats and another dog, free range pigs, goats, sheep and deer? The majority of these have had no contact whatsoever with sentinel, tested slaughtered cattle, but are victims of increasing spillback from environmental contamination on a scale we have not experienced before. The level of infectivety sustained and spread within herds of some of these species, indicates the real possibility of a second or third reservoir of tuberculosis.

Is VLA's next 'research' project to develop BCG for all mammalian species (including human beings) so that tuberculous infected badgers can roam free?

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