Last year, as bluetongue disease moved northwards through France, Germany, Belgium, the Netherlands, Luxembourg and Denmark, Ireland devised a plan to combat it.
By September, the disease, which is a viral infection of most domestic and wild ruminants such as cattle, sheep, goats and deer, had travelled the English Channel into Britain.
This week bluetongue, which is spread by biting midges of the Culicoides species, found its way to Ireland in a heifer imported into Co Antrim.
Most veterinary and climatic experts believe that with global warming Ireland cannot expect to keep out a disease which has spread rapidly since 2006 from Mediterranean areas.
A paper prepared by an expert group dealing with the disease warned that it could arrive here in an animal already carrying the infection.
If the weather conditions were favourable, the midges could then infect other animals.
It said prevailing winds could spread infected midges to Ireland from infected areas of Europe, and the disease might also arrive here through the importation of infected semen or other biological products.
A study of the midge population in Ireland by NUI Galway has found that of the 16 most common types here, eight are potential vectors for bluetongue virus infection. These feed on livestock mainly between dawn and dusk, but can operate 24 hours a day.
Infection is transmitted when an uninfected midge takes blood from an infected animal. If the temperature is high enough, the virus will develop inside the midge, which will give it to a new host animal.
It takes between four and 20 days, depending on the animal, its age and the strain of virus, for the new animal to become infected.
Unfortunately, most animals with the disease show no sign of illness but in those that become sick the virus causes fever and will damage blood vessels causing them to leak into the tissues of the face and extremities.
Affected animals have swollen muzzles, lips and tongues, and some will have eroded gums and drool profusely. They go off their feed, lose condition rapidly and their muscles may degenerate. Those that survive face a long recovery.
An outbreak of the disease in Ireland would have a significant impact on the live export and semen embryo trade as restrictions would remain in place for quite some time.
Where there is a bluetongue outbreak, the EU demands that national governments place a 20km control zone, a 100km protection zone and a 150km surveillance zone around any infected farm. Movements of animals are restricted in these zones.
Animals must be kept indoors when midges are active, and control/eradication of the midges' habitat and use of insecticides are ordered.
Unlike foot-and-mouth disease, national governments do not have to slaughter all animals on a farm where the disease is found. However, the infected or suspected animals must be killed and carcases destroyed.
Last year the EU realised that all of the the union will be infected so it commissioned the development of a vaccine which is not yet ready.
Ireland has ordered 250,000 units of the vaccine, but whether it will be used will depend on the extent of any outbreak.