A breeding stallion in West Sussex, England, has tested positive for equine viral arteritis (EVA), according to a report filed by the British equestrian magazine Horse & Hound.

The confirmation of the EVA was announced Dec. 8, however there is little further information regarding the case.

"Breeding restrictions have been put in place on the infected stallion and investigations have begun to establish the likely origin of the infection, as well as any mares that may have been affected," the British Department for Environment Food and Rural Affairs said in a statement.

EVA is a highly contagious viral infection that causes a high rate of abortion among pregnant mares. Peter J. Timoney, MVB, PhD, FRCVS, former director of the University of Kentucky's Gluck Equine Research Center, a leading world authority on EVA, elaborates on the potential contagiousness of EVA, noting, "In the acutely infected horse, irrespective of whether it is a gelding, mare, or stallion, the virus can be spread from the respiratory tract for one to 2.5 weeks. In urine, it may be shed in lesser concentrations for up to three weeks. During the acute phase of infection, virus is also shed into the conjunctival sac (in the eye) and the alimentary (GI) tract, and virus is found in feces for a short period following the onset of infection."

The disease causes damage to a horse's arteries and is transmitted through the respiratory tract--coughing and snorting--or venereally via semen from an infected stallion. EVA has a wide range of clinical signs (including fever, conjunctivitis, and swelling of the lower legs) but is most dangerous to in-foal mares. There is no treatment yet available for the disease.

Another stallion from Staffordshire, England, tested positive for EVA in August.

Earlier this year, there was a large scale EVA outbreak in Argentina that included 12 farms in the Buenos Aries province. The virus was first detected March 31, and continued for several months.

More information on the most recent case of EVA will be posted on TheHorse.com as it becomes available.

About the Author

Erica Larson, News Editor

Erica Larson, news editor, holds a degree in journalism with an external specialty in equine science from Michigan State University in East Lansing. A Massachusetts native, she grew up in the saddle and has dabbled in a variety of disciplines including foxhunting, saddle seat, and mounted games. Currently, Erica competes in eventing with her OTTB, Dorado.

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