A highly contagious livestock virus that causes lesions in horses and cattle has appeared in two Utah counties, the Utah Department of Agriculture and Food announced Wednesday.

Several farms in Uintah and Emery counties have been placed on a 14-day quarantine after vesicular stomatitis virus (VSV), Indiana type, was diagnosed, officials said in a news release.

“Four more premises are currently under investigation," the release stated. "Samples that were submitted for testing should yield results before the end of the week.”

With confirmed cases in the state, the release added, “it is essential that veterinarians and livestock owners be on the alert for animals displaying clinical signs of the disease.”

Vesicular stomatitis is a viral disease that primarily affects horses and cattle and occasionally swine, sheep, goats, llamas and alpacas. Rarely, humans can become infected with the disease when handling affected animals.

Excessive salivation often is the first sign of the disease. Close examination of the mouth initially reveals blisterlike lesions on the inner surfaces of the lips, gums, tongue and dental pad. Lesions also can form on the lips, nostrils, coronary band, prepuce, vulva and teats.

The blisters swell and break, which causes oral pain, discomfort and reluctance to eat or drink. Lameness and severe weight loss may follow. Diagnosis requires testing of samples at an approved facility.

Good sanitation and quarantine practices on affected farms usually contain the infection. When a definite diagnosis is made, the following procedures are recommended:

• Separate animals with lesions from healthy animals. Animals on pastures tend to be affected more frequently with this disease.

• As a precautionary measure, do not move animals from the premises until at least 14 days after lesions in the last affected animal have healed.

• Control insects by eliminating or reducing breeding areas; use insecticide sprays or insecticide-treated ear tags on animals.

• Use personal protective measures when handling affected animals to avoid human exposure.

Veterinarians and livestock owners who suspect an animal may have vesicular stomatitis or any other vesicular disease should contact the state veterinarian at 801-5638-7162 or the U.S. Department of Agriculture’s Veterinary Services at 801-525-5010.