Email from Dr Colin Fink February 5 2009
Caroline Cranbrook has kindly brought your question to my attention.
A number of variables must be considered for any assessment of what is a reasonable charge for this service:
- Is it to be supplied as a public service at cost? #
- Will the service be on batched samples and therefore a large number of samples run at once ? This reduces costs, or alternatively, is the service to be a rapid on demand diagnostic service? - more expensive to administer and run .
- Is it to be a 'nested' PCR reaction or a single round - a 'nested' reaction amplifies a part of the unique organism cDNA* - to prove that the organism is within the sample, and then a second round of amplification is undertaken using the cDNA product of the first reaction and choosing to amplify a part of this material . This second round increases the amplification and therefore the sensitivity of the assay and also removes any possibility of the amplification of cDNA being other than that specific for the organism.
- Is the service to be an exclusive public sector activity with intentional public sector exclusion of any private contractor? This exclusion may be achieved by creating rules of accreditation for the diagnostic exercise impossible for outside contractors to implement? This will remove any competition and price challenge. One way to ensure this exclusion will be for the public sector to fail to cooperate with any supply of control material. Alas, MAFF/DEFRA managed this so well with Foot & Mouth.
# Some useful diagnostic guidance for herds/flocks may be obtained using an antibody assay. It will allow us very cheaply to see whether any animals have been exposed.
* Blue tongue is an RNA virus. This must be copied by the enzyme reverse transcriptase into copy DNA (cDNA) before amplification This adds an extra step to the diagnostic assay.
So in summary, an isolated PCR test for Blue tongue may cost £30. However with a little good administration this could be reduced considerably with a large scale undertaking.
Hope that make a little sense.?