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. 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.
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. In many other countries meat and milk from vaccinated animals are routinely consumed.