French EVA Outbreak Stabilizing

A stallion, several mares, and a foal have tested positive for equine viral arteritis (EVA) at two French Lusitano farms in a new outbreak of a disease not seen in France since 2007, according to a European equine pathology surveillance network. The mares suffered fertility issues, including abortion, and the foal died.

"To our knowledge, several problems of reproduction were reported in the breeding center where the foal died: embryonic reabsorption, low fertility, and infertility," said Christel Marcillaud Pitel, director of the Réseau d'Epidémio-Surveillance en Pathologie Equine in Caen, France. "There was only one case of an abortion causing an expulsed fetus, and the fetus was born alive but very weak, and it died within 48 hours."

The outbreak occurred in two neighboring farms in southeast France near Marseille and Montpellier. The outbreak appears to be limited to a Lusitano breeding program in the area, Marcillaud Pitel said. The affected stallion's semen was not shipped for artificial insemination because he only provides live cover, she added.

Analyses revealed that both farms were affected by the same strain of the virus, but the origin of the outbreak is unknown.

The two farms have been quarantined since the first case was detected in late June. Any horses that left the sites prior to the quarantine have been tested for EVA. Results are pending, but the situation appears to be stabilizing, Marcillaud Pitel said.

The last EVA outbreak in France began in July 2007 and affected 26 farms in Normandy, including the French national stud at Haras du Pin.

"For the moment (the current outbreak) is of a weaker amplitude because it's localized in just these two sites," Marcillaud Pitel said. "The virus also seems less virulent (than the one in 2007): the symptoms are less remarkable, and it is less widespread among the individuals."

The disease, which is caused by the equine arteritis virus, can cause fever, edema, and abortion and is mainly transmitted through semen. Affected horses can carry the virus for life after the acute stages of the illness have passed. During the acute stage the virus can also be transmitted via respiratory secretions.

About the Author

Christa Lesté-Lasserre, MA

Christa Lesté-Lasserre is a freelance writer based in France. A native of Dallas, Texas, Lesté-Lasserre grew up riding Quarter Horses, Appaloosas, and Shetland Ponies. She holds a master’s degree in English, specializing in creative writing, from the University of Mississippi in Oxford and earned a bachelor's in journalism and creative writing with a minor in sciences from Baylor University in Waco, Texas. She currently keeps her two Trakehners at home near Paris. Follow Lesté-Lasserre on Twitter @christalestelas.

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