I heard most of this item and it was clear that Prof King's scientific credibility was left in tatters.

 

One statement he made (more than once, and forcefully) blatantly ignored the most basic scientific principles.

 

If you remember, back in March MAFF engaged three lots of consultants to model the epidemic. They each produced predictions from three scenarios:

 

- continue as up to then

- cull infected farms inside 24 hours

- do this as well as contiguous cull within 48 hours.

 

We were told then that the models showed that only the last scenario would work. As we know, since then the third scenario has been followed with puritanical zeal - and the course of the disease has indeed followed the curve predicted.

 

King was challenged this morning on whether the contiguous cull was necessary. He said that the fact that the epidemic had followed the predicted course was proof that the contiguous cull was indeed necessary. However, this is NOT what the data shows - nor could it possibly show that.

 

Essentially the question he was being asked was: was contiguous culling necessary, or would culling of infected farms within 24 hours have worked on its own? If the data is to distinguish between these situations, they must each have been tried separately. However, they were both done at the same time! Therefore the most you can say is that it APPEARS that doing both together worked (you can never, of course, be certain that the "successful" curve was not produced by weather, luck, the movement ban or something else altogether). Anyone with any scientific integrity at all (even one as out of date as me) would never make the statement he made on the evidence available. (The national curriculum as covered by my ten-year-old daughter includes the concept of the "fair test". This was not one!)

 

There are two more fundamental flaws in the case King was trying to make.

 

One is that the "three scenarios" did not include vaccination. There is no scientific justification I can think of for this. I believe the consultant experts were unprofessional in not insisting that all realistic scenarios were included. I suspect that the curve from a vaccination scenario just showed too vertical a drop to be allowed to appear on the same graph!

 

The second flaw is, as I understand it, that the three sets of consultants were using versions of the same model. This is very poor practice. Models of this kind are often very sensitive to which mathematical basis they use, and the weight given to the many different data items (in fact the criticism in the instance above was exactly such a one - that the models gave undue weight to the efficiency of airborne infection). This is why it is good practice to use several independent teams (which was done), to make sure that they are using independent models (which does not seem to have been done), and to make sure that the models are run with a wide range of values (which as far as I can see was not done).

 

It seems to me that the models were not properly tested to see whether they were unduly sensitive to inaccurate estimates of data such as the efficiencies of the various viral transmission methods. I should be delighted to be proved wrong.

 

Personally (speaking as a mere ecologist, and admittedly without the benefit of much data) I am very doubtful that air-borne transmission is a significant factor compared with mechanical dispersal (vehicles etc) and animal-to-animal contact. It is noticeable that after the first 20 days almost no single case occurred more than a mile or two from another (see Andrew Heggie's animated map on www.hjones-sons.co.uk/fmdani.htm).

 

It's curious that the contiguous cull is justified by exactly the same arguments which are ignored when it comes to deciding whether GM maize (a wind-pollinated plant) can contaminate other maize crops!

 

You can find the "three scenarios" graphs on: www.maff.gov.uk/animalh/diseases/fmd/news/king.asp (linked to www.maff.gov.uk/animalh/diseases/fmd/news/king.pdf) This is from the Imperial College report - I remember at least one of the other versions being on the MAFF site at one time, but can't now find it.