FIRST RECORDED OUTBREAK OF EQUINE VIRAL ARTERITIS IN THE UNITED-KINGDOM

Equine viral arteritis was diagnosed for the first time in the United Kingdom in 1993. The outbreak began on a non-thoroughbred stud in sout h Nottinghamshire and spread to five other premises through chilled se men used for artificial insemination and from acutely and subclinicall y infected mares returning home. The outbreak was contained on these s ix premises by means of voluntary movement restrictions. The most comm only observed clinical signs were typical: pyrexia with depression, an d conjunctivitis with periorbital oedema; nasal discharge, and oedema of the distal limbs, prepuce and mammary glands were less common. The first mare to be covered by a recently imported stallion was the first animal to be affected. The mare was resident and no new mares had arr ived on the stud during the previous five months. About 100 animals be came infected during the outbreak, including three indigenous stallion s. Equine arteritis virus was isolated from semen and heparinised bloo d samples and sero-conversions were demonstrated by using the equine a rteritis virus neutralisation test. Although the outbreak was containe d, the free movement of animals within the European Union increases th e possibility of infected stallions being introduced into the UK.