What is foot-and-mouth disease?
It is a highly infectious viral disease that may even be transmitted through dust particles in the air and can prove fatal in pigs, cattle sheep and goats. Infected animals' hooves and mouths become blistered causing lameness, increased salivation and loss of appetite. They rapidly lose weight and produce less milk.

Can animals recover from it?
Foot-and-mouth kills a small percentage of affected animals - mostly the old and young. Most animals could recover from the virus although it might leave them weak and lame.

There is a vaccine available which is rarely used in the European Union, but widely used in some other parts of the world.

If a vaccine is available - why don't we use it?
Vaccination is ruled out mainly for commercial reasons. Vets say vaccinated animals, although free of symptoms, can carry the virus and pass it on to other animals. As a result countries considered free of the disease refuse to import vaccinated livestock.

If the UK decided on vaccination instead of slaughter it would be unable to export livestock to key markets in Europe and the USA.

Vets in the UK believe the best way of stopping the spread of foot-and-mouth is to destroy any affected herd, incinerate the carcasses and isolate all affected farms inside a five-mile radius exclusion zone.

Another argument against vaccination is that blood tests to distinguish animals which have received vaccines from animals which have contracted the disease are not recognised internationally.

There are seven main types of the foot-and-mouth virus and several subtypes of each. The UK virus is "sub-type O".

Vaccination might be considered in some parts of the EU if other measures fail to control the epidemic.

The EU currently has three centres where there are emergency stocks of antigens that could be used to make vaccines against foot-and-mouth disease: Pirbright in the UK, Lyon in France, and Brescia in Italy.

Before 2001, when was the last epidemic in the UK?
The most recent outbreak in Britain was in 1981 on the Isle of Wight - when 200 cattle and 369 pigs were destroyed. But the last major epidemic was in 1967 and ended in the slaughter of 442,000 animals after more than 2,364 outbreaks were detected.

It cost the country an estimated �150m in slaughter costs and lost sales in 1967 and 1968. A total of �27m was paid out to farmers in compensation.

Farms had to be scrubbed with disinfectant twice a day and animals were not allowed on to the land for at least six months after the slaughter. The worst outbreaks were in Wales, Cheshire, Shropshire.

Are humans in danger?
No. Doctors say there is no risk to human health. During the 1967 epidemic one human was diagnosed as having caught the disease and one child was suspected of having it. The disease should not be confused with the similarly named, but completely different condition called hand, foot and mouth disease, which can infect and cause illness, particularly in children.

What other countries have it?
Foot-and-mouth disease is endemic in many parts of the world, including Africa, the Middle East, Asia and South America. It was thought to have been virtually eradicated in Europe. Until now the most recent outbreak was in Greece last year. North and central America, the Pacific nations and the Caribbean are free of the virus.

If it is so dangerous, why are some animals being moved around the country?
A limited number of unaffected livestock are now being moved to abattoirs under strictly controlled conditions. Temporary movement licences have been granted the by the Ministry of Agriculture to a number of farmers in the hope that the move will help ease meat shortages and aid an industry on the brink of bankruptcy.

The government's chief veterinary officer Jim Scudamore said relaxing the ban would not spread the disease as all the animals would come from uninfected areas and would be examined before they were transported and again at the abattoir.

Agriculture minister Nick Brown also said there was little risk that the disease would spread as a result of the relaxation - although he also said: "I'm very conscious that in 1967, in that outbreak they believed they had it under control, relaxed controls and then it broke out again."