Horses on two Montrose County and one Delta County premises have tested positive for vesicular stomatitis (VS) and have been placed under quarantine, the Colorado Department of Agriculture (CDA) reported July 2.
Colorado has become the fourth state in the country to have confirmed equine VS cases in 2015. Previous positive cases of vesicular stomatitis this year have been diagnosed in Arizona, New Mexico, and Texas.
On July 2, the National Veterinary Services Laboratory reported positive tests. The initial Colorado disease investigations were accomplished by field veterinarians from the state veterinarian’s office at the Colorado Department of Agriculture.
“The primary spread of VS is thought to occur through insect vectors; the horses involved in these cases have no history of travel,” said State Veterinarian Keith Roehr, DVM. “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.”
A 2014 VS outbreak resulted in 556 livestock investigations in Colorado and 370 quarantines. The final quarantines were released in January 2015.
A number of species are susceptible to VS, including horses, mules, cattle, bison, sheep, goats, pigs, and camelids. The clinical signs of the disease include vesicles, erosions, and sloughing of the skin on the muzzle, tongue, and teats and above the hooves of susceptible livestock. Vesicles are usually only seen early in the course of the disease.
Disease transmission is not completely understood, but components include insect vectors, mechanical transmission, and livestock movement.
While rare, human cases of VS can occur, usually among those who handle infected animals. In humans VS can cause flu-like symptoms and only rarely includes lesions or blisters.
New for 2015 VS investigations is that the USDA has delisted VS as a foreign animal disease in horses; VS continues to be listed as a foreign animal disease for cattle and other livestock. This USDA procedural change will allow greater flexibility in how VS is managed in respect to equine cases. The primary change will now be that quarantines can be released as soon as 14 days after the onset of clinical signs of the last affected horse on a premises.
“Science has shown that the transmission of the virus is for a brief period of time after the initial clinical signs of VS,” said Reohr. “Our goal is to appropriately adjust our response to this disease to reduce the negative economic impact to the equine community.”
With the delisting of VS as a foreign animal disease, Colorado veterinarians can now take a lead role in the management of the disease in equine cases. In earlier cases, CDA or USDA field vets were required to perform the disease investigations on horses; the delisting now allows local veterinarians to perform the initial investigations, collect samples, and collaborate with animal health officials regarding movement restrictions and quarantines.
The Colorado State University Veterinary Diagnostic Laboratory has been approved to perform VS tests on horses in Colorado, which can provide a more timely response on test results.
Owners can remember the following tips:
- 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. A list of contact information for all state veterinarians’ offices is available at www.colorado.gov/aganimals and click on "Import Requirements."
- Colorado fairs, livestock exhibitions, and rodeos could institute new entry requirements based on the extent and severity of VS outbreaks. Certificates of veterinary inspections issued two to five days prior to an event can beneficial to reduce risks. Be sure to stay informed of any new livestock event requirements.
- During an event, important VS disease prevention procedures include minimizing the sharing of water and feed/equipment, applying insect repellent daily (especially to the animals ears), and closely observing animals for signs of VS.
- If moving livestock internationally please contact the USDA Animal and Plant Health Inspection Service Veterinary Services’ Colorado office at 303/231-5385 to determine if there are any movement restrictions or testing requirements for VS.
Source : TheHorse