VS infection found in horse in south Texas

Austin, Texas

-- What is reported to be the nation's first case of vesicular stomatitis (VS) for 2009 was detected in a horse in Starr County, one of Texas' southernmost counties.

Endemic to the United States, the disease occurs sporadically, affecting horses, cattle, sheep, pigs, deer and a few other species. Signs include blisters, lesions and sloughing of the skin on the muzzles, tongue, teats and above the hooves of livestock.

The most recent serious outbreak was in 2006 in Wyoming, affecting 17 horses and 12 cattle on 13 premises, according to Dr. Bob Hillman, Texas state veterinarian and head of the Texas Animal Health Commission (TAHC).

Horses often are the signal, or first, animal to be seen with the disease when the virus is active. Blisters and lesions seen on cattle, sheep, pigs or other cloven-hoof animals raises a concern for foot-and-mouth disease, to which horses are not susceptible.

Several states and countries place additional entry requirements or restrictions on the movement of animals from VS-affected states, so livestock owners are advised to check with the place of destination before moving animals, to avoid having shipments turned back or possible legal action by animal-health officials, Hillman says. Florida recently announced such VS restrictions.

Anyone who notices blisters or unusual sores on livestock should have the animals examined by a veterinarian, he advises.

VS lesions, while painful, often heal within two to four weeks, but in severe cases some may elect to have a suffering animal euthanized. Treatment involves supportive care and antibiotics to prevent secondary infections. Most states quarantine VS-infected animals and herdmates until three weeks after the lesions heal.

Sand flies and black flies are believed to play a role in VS transmission.