Broomfield, Colo. – Cases of vesicular stomatitis (VSV) have been identified in the following 35 Colorado counties: Adams, Alamosa, Arapahoe, Archuleta, Boulder, Broomfield, Chaffee, Conejos, Delta, Dolores, Douglas, Eagle, El Paso, Fremont, Garfield, Gilpin, Grand, Gunnison, Jefferson, La Plata, Larimer, Las Animas, Mesa, Mineral, Montezuma, Montrose, Morgan, Ouray, Park, Pueblo, Rio Blanco, San Miguel, Summit, Teller, and Weld. There are currently 18 quarantines remaining in 13 counties. The total count of premises under quarantine for VSV by county is updated regularly on the CDA VSV website.
Although the majority of quarantines have been released, many horse and livestock movements are still impacted by VSV import requirements in other states. Many states have very stringent import requirements; for example, animals within 10 miles of a VSV quarantined premises in the previous 30, 60, or 90 days may not enter their state. Accredited veterinarians must ensure that horses and livestock meet the import requirements of destination states. Veterinarians can contact the State Veterinarian’s Office at 303-869-9130 with questions regarding health certificates.
The first case of VSV in Colorado was reported on July 3, 2019, in Weld County by a field veterinarian from the State Veterinarian’s Office at the Colorado Department of Agriculture. An incursion of VSV-infected insect vectors is the likely source of infection. There are no USDA approved vaccines for VSV.
Please see the USDA APHIS Veterinary Services website to read the current situation report for all confirmed cases in the U.S.
Vesicular Stomatitis Background
Vesicular stomatitis is a viral disease that primarily affects horses and cattle but occasionally swine, sheep, goats, llamas, and alpacas will show clinical signs. The transmission process of VSV is not completely understood, but includes insect vectors such as black flies, sand flies, and biting midges.
The incubation period ranges from 2-8 days. Clinical signs include vesicles, erosions, and sloughing of the skin on the muzzle, tongue, ears, teats, and coronary bands. Often excessive salivation is the first sign of disease, along with a reluctance to eat or drink. Lameness and weight loss may follow.
Humans may become infected when handling affected animals, but this is a rare event. To avoid human exposure, individuals should use personal protective measures when handling affected animals.
Tips for Livestock Owners
- Strict fly control is an important factor to inhibit the transmission of the disease.
- Avoid transferring feeding equipment, cleaning tools or health care equipment from other herds.
- Colorado veterinarians and livestock owners should contact the state of destination when moving livestock interstate to ensure that all import requirements are met. Contact information for all state veterinarian offices is listed here.
- Colorado fairs, livestock exhibitions, and rodeos may institute new entry requirements based on the extent and severity of the current VS outbreak. Certificates of veterinary inspection (CVIs or health certificates) issued within 2-5 days prior to an event can be beneficial in reducing risks. Be sure to stay informed of any new livestock event requirements. See the Vesicular Stomatitis Guidelines for Shows and Fairs.
Important Points for Veterinarians and Horse Owners
Any vesicular disease of livestock is reportable to the State Veterinarian’s Office in Colorado – to report call 303-869-9130. If after hours, the voice message will indicate which staff veterinarian is on call.