Four horses in Colorado have been confirmed with vesicular stomatitis, adding to the 11 horses and two cattle in Texas already diagnosed with the disease.
The National Veterinary Services Laboratories in Ames, Iowa, confirmed on Thursday that vesicular stomatitis virus (VSV) infection had been confirmed on two equine premises in Weld County, Colorado. Both properties have been placed under quarantine.
Three affected horses were on one premises and one affected horse on the other, according to the latest update from the Animal and Plant Health Inspection Service, part of the US Department of Agriculture.
All cases involved the New Jersey serotype.
The laboratory confirmed the Colorado cases all met the case definition of VSV infection, with compatible clinical signs and either positive complement fixation antibody titers or positive virus isolation.
To date, 12 VSV-positive premises have been identified in Colorado and Texas. One property, in Kinney County, Texas, has been released from quarantine and there are currently seven other properties in Texas on a 21-day countdown to quarantine release.
Colorado State veterinarian Keith Roehr said vesicular stomatitis can be painful for animals and costly to their owners.
“The virus typically causes oral blisters and sores that can be painful, causing difficulty in eating and drinking.”
Equids, mules, cattle, bison, sheep, goats, pigs, and camelids are all susceptible to the disease.
Clinical signs include vesicles, erosions, and sloughing of the skin on the muzzle, tongue, teats, and above the hooves of affected livestock – symptoms similar to those of foot and mouth disease.
Vesicles are usually seen only early in the course of the disease. The transmission of VS is not completely understood, but components include insect vectors, mechanical transmission, and livestock movement.
While rare, human cases can occur, usually among those who handle infected animals. In humans the disease can cause flu-like symptoms and only rarely includes lesions or blisters.
Authorities says that veterinarians and livestock owners who suspect an animal could have VS or any other vesicular disease should immediately contact state or federal animal health authorities.
Livestock with clinical signs of the disease are isolated until they are healed and determined to be of no further threat for disease spread. There are no vaccines approved by the US Department of Agriculture for VS.
Strict fly control is an important factor to inhibit the transmission of the disease. Authorities also recommend against transferring feeding equipment, cleaning tools or health care equipment between herds.
More information on vesicular stomatitis can be found here.