What could vaccination achieve?

Some scientists say vaccination should be used to speed the end of the epidemic. Professor Fred Brown, who helped to tackle the 1967 outbreak, says the virus will become more active and virulent as temperatures drop with winter approaching. Sheep will be moving down from the hills to lowland pastures, and there are fears of many more cases. But other scientists say the vaccine would not offer any advantages over mass slaughter.

What are the arguments against vaccination?

It takes four days to work, and even then may not be completely effective. Vaccinated animals can still carry the virus and pass it on, without showing any symptoms. There would be a marked effect on UK exports: some could continue, but British meat would be barred from the US, and vaccinated British animals could not be exported there or to Japan. Total meat and livestock exports amount to about �310m ($460m) a year. The Dutch used vaccination, but many experts say the situation there was significantly different. The outbreak was localised, and vaccination provided a ring of animals round the strongholds of the virus. All were slaughtered later. In the UK, the outbreak had raced across the country before anyone knew it was here, let alone begun working to eradicate it.

Could people safely eat the meat of vaccinated animals and drink their milk?

Yes. Foot-and-mouth disease is not a risk to human health. In many other countries meat and milk from vaccinated animals are routinely consumed. The Food Standards Agency says: "Millions of doses of vaccine have been given world-wide with no adverse effects on human health. Foot-and-mouth disease vaccines are widely used throughout the developing world in parts of Africa, South America and Central America. If people go abroad on holiday to countries where the vaccine is routinely used and eat meat, that meat has probably been vaccinated and has never been shown to cause any human health problems. In mainland Europe (including the Netherlands, France, West Germany, Belgium, Italy, Spain and Switzerland), people were drinking milk and eating meat from animals vaccinated against the disease up until 1991." The FSA told BBC News Online: "There is no evidence of any consumer resistance in countries which routinely use vaccination."

Could vaccination prevent future outbreaks?

No. There are several strains of foot-and-mouth, and vaccines work against only one strain of the virus. Anyway, animals need booster shots every six months or so. And the UK would not be able to regain its "foot-and-mouth free" export status while vaccination continued.

What do farmers think about vaccination?

Many are understandably confused. Early on in the outbreak the then Agriculture Minister, Nick Brown, said that using vaccination would be a "substantial retreat". The government has argued - largely from concern over lost export markets - that vaccination would not help. The export trade is worth far less than the damage done to tourism and the wider rural economy. But even critics of the government say the countryside will not recover until foot-and-mouth is beaten.

The National Farmers' Union has opposed vaccination consistently. The NFU president, Ben Gill, said: "These are not simply economic concerns, as some have suggested.

"There is a real possibility that the use of vaccination could actually prolong this outbreak, resulting in the culling of more cattle rather than less. This has happened elsewhere in the world.

"Once we go down this road there will be no going back. And it is farmers throughout the UK - not just in vaccinated areas and not only cattle farmers - who will have to bear the consequences for a very long time to come."

Despite that, some farmers, and many outside the industry believe that mass slaughter was the wrong approach.

They accept that seriously ill animals should be slaughtered on humane grounds, but believe that vaccination could have spared many more. That would have meant spotting the disease far earlier.