A horse has been diagnosed with vesicular stomatitis in Colorado, following a series of cases in New Mexico. It is the first case of the disease in Colorado in six years.
The Colorado Department of Agriculture says a property in Las Animas County is under quarantine after a horse tested positive for the disease, the symptoms of which are similar to those of foot and mouth disease.
The affected horse had not recently traveled and is believed to have been infected by insects.
Susceptible animals include horses, cattle, sheep, pigs and deer. Signs include vesicles, erosions and sloughing of the skin on the muzzle, tongue, teats and above the hooves of susceptible livestock. Vesicles are usually seen only early in the course of the disease.
As it progresses, ruptured vesicles erode to produce areas where dead tissue becomes separated from the surrounding wound near the mouth or hoof. Animals with oral lesions may refuse to eat or drink due to discomfort. Coronary band lesions can result in lameness in one or more feet.
In severe situations, the hoof may slough or hoof growth may be permanently impacted.
While rare, human cases can occur, usually among those who handle infected animals. VS in humans can cause flu-like symptoms and only rarely includes lesions or blisters.
Colorado state veterinarian Keith Roehr said: “While this is the first case diagnosed in Colorado in 2012, there have been several cases identified in the Rio Grande River valley of New Mexico,”
“This Colorado case represents a northern movement of the virus that has been typical in past years.”
Vesicular stomatitis is classified as a foreign animal disease. It occurs sporadically in certain areas of the western United States.
In response to the case, the Colorado State Veterinarian’s Office issued travel requirement rules for horses, mules, cattle, bison, sheep, goats, swine, and camelids entering from states with confirmed cases of the disease.
The requirement states that health certificates should certify that the veterinarian issuing the certificate has examined the animal(s) and have found no signs of vesicular stomatitis. Vets must also certify that the animals have not originated from any premises under quarantine for the disease.
“The purpose of this requirement is to ensure that veterinarians issuing health certificates are aware of the spread of vesicular stomatitis and are vigilant in looking for signs of the virus,” Roehr said.
“VS can be painful for the animals and costly to their owners. While this virus does not typically cause death, the animal can suffer from painful sores so it is important to monitor herds for symptoms.”
Authorities have urged animal owners to strictly control flies to inhibit the transmission of the disease.
They are also urged to avoid transferring feeding equipment, cleaning tools or health care equipment from other herds.
Colorado fairs, livestock exhibitions, and rodeos may institute new entry requirements based on the extent and severity of the current outbreak.
Veterinarians and livestock owners who suspect an animal may have VS or any other vesicular disease should immediately contact state or federal animal health authorities. Livestock diagnosed with the disease are isolated until they are free from clinical signs of disease and no longer present a risk to other livestock.
There are no US Department of Agriculture approved vaccines for VS.
In New Mexico, 20 premises remain under quarantine as a result of what New Mexico agriculture authorities have described as a significant outbreak. Affected New Mexico counties are Lincoln, Rio Arriba, Sandoval, Socorro, and Valencia.
Kentucky state veterinarian Robert Stout has prohibited entry of all livestock, wild and exotic animals into Kentucky from New Mexico or Colorado premises currently under quarantine, or any such animal that has been on a premises during the 30 days preceding the entry into Kentucky. He requires a matching declaration on veterinary certificates.