The consensus is that vaccination is the most effective way of halting infection if the disease spreads to other areas. This becomes more likely the more outbreaks there are.
Vaccination is now at the forefront of European foot and mouth control strategies. New EU legislation places more emphasis on it and its use was recommended in the government's own review of the 2001 outbreak.
Britain came within hours of vaccinating cattle in 2001 after it was recommended by vets to protect animals in Cumbria and Devon. But farm leaders were sceptical and the food industry lobbied strongly for it not to be used because it was concerned it would affect export markets and put off consumers.
"The huge disincentive against vaccinating is that under trade rules any vaccinated animals have to go into a separate supply chain. This is costly and puts business off," said Lawrence Woodward, director of the Elm Farm organic research centre.
Britain keeps stocks of the eight most common strains of FMD at the Pirbright laboratory world vaccine bank, but because the strain that has escaped is unusual, the government this week contracted with Merial, a pharmaceutical company, to make 300,000 doses. But vaccination is costly, animals have to be vaccinated twice and there is a possibility that vaccinated animals can spread the disease.