The President of the National Farmers' Union, Ben Gill, met Tony Blair this morning to discuss the Foot and Mouth disease.

He emerged from Downing Street with a surprisingly upbeat message: there were positive signs that the present policy of mass slaughter was beginning to work.

Reluctant

Mr Gill remains reluctant to accept the need for a vaccination programme, even though the European Union has given its permission.

Downing Street has acknowledged that a decision will be taken within 48 hours, and that it would only apply to Cumbria.

As we've reported on the World at One this week, the EU does have a contingency plan for emergency vaccination against Foot and Mouth, and Britain would seem to be a prime candidate.

Vaccination is not the solution in itself

NFU President Ben Gill

But Mr Gill is at pains to point out the disadvantages.

"The use of a blanket vaccination is very much a secondary option compared to a complete cull," he said.

Vectors

"Wherever you vaccinate, even if you do a barrier vaccination, it takes ten to 14 days to be effective, so where do you put the barrier? Some of those animals become active vectors of the virus and spread it around in their breath."

Vaccination: decision within 48 hours

So far the EU has only given its permission for vaccination of a hundred thousand cattle in Cumbria.

But the Dutch virologist, Dr Simon Barteling -- one of the authors of the EU report on how to tackle Foot and Mouth Disease by vaccination -- believes that the time has come for its full recommendations to be introduced here.

Time has come

The only way to control the disease is to vaccinate with a potent vaccine in a systematic way

Dr Simon Barteling

But the Dutch virologist, Dr Simon Barteling -- one of the authors of the EU report on how to tackle Foot and Mouth Disease by vaccination -- believes that the time has come for its full recommendations to be introduced here.

He told me: "In the areas where the disease has occurred so far. You have to vaccinate all the animals that are susceptible. And for the rest of the country, all the cattle must be vaccinated."