Ireland’s Department of Agriculture and Rural Development (DARD) issued advice on April 5 to horse breeders because of concerns over the perceived risk increase for equine viral arteritis (EVA).

Tests on horses from two Irish studs have shown evidence of exposure to the disease, and the positive test results are believed to be linked to a previously reported outbreak of EVA at an Irish stud in 2003 (an unvaccinated stallion tested seropositive for EVA during 2003).

EVA is an acute, contagious, viral equine disease that can cause fever, respiratory illness, ocular inflammation, edema (swelling), weakness or sickness in foals, and abortion. It can be transmitted through respiratory or venereal routes. It occurs worldwide and is present in Great Britain, the United States, and every mainland European country.

Mares shipped from Ireland to Britain are being tested for EVA. This practice has been routine in recent years for mares visiting Britain from the rest of Europe. British stallions are vaccinated twice a year against EVA, a practice that has been resumed following an interruption in the supply of vaccine early last year