Vesicular Stomatitis cases on the rise
Both Texas and Colorado have seen a surge in Vesicular Stomatitis (VS) cases this summer, and that has local and state official watching animal movement a little closer. The numbers have surpassed 200 in both states, with primarily horses making the list, but the two states now have added cattle to the numbers of infected. This is the first case of VS in cattle in the U.S. since 2006, according to the Texas Animal Health Commission (TAHC).
VS can cause blisters and sores in the mouth and on the tongue, muzzle, teats or hooves of horses, cattle, swine, sheep, goats, llamas and a number of other animals. VS can be painful for animals and costly to their owners. The sores can be painful causing difficulty in eating and drinking and will typically heal in two or three weeks, but VS is highly contagious.
The Colorado Department of Agriculture’s (CDA) State Veterinarian’s Office has placed 133 locations under quarantine as of last week, after horses and cows tested positive for Vesicular Stomatitis (VS). Results on additional tests are pending. In Texas, as of last week, 54 premises in 11 counties have been confirmed with VS.
The outbreak has some states requiring some added paperwork for owners bringing animals in. For example, California entry requires all horses, cattle and swine originating from any state where VS has been diagnosed since May 27, 2014, to be accompanied by a health certificate and signed by an accredited veterinarian that includes the following statement:
“The animals represented on this certificate have not originated from a premises or area under quarantine for vesicular stomatitis, or a premises on which VS has been diagnosed in the past 30 days. I have examined the animals and have found no signs of vesicular stomatitis.” Cattle and swine being transported directly to slaughter are not included.
Florida has similar restrictions, including a “permission number” required, but in that state, slaughter animals are not exempt from the extra restrictions. In Idaho, no livestock may enter from states where VS has been diagnosed, if the animals have been housed within 10 miles of a VS premises of origin within the last 30 days. Other animals must have a certificate of inspection that includes a veterinarian inspection and statement.
Illinois, Louisiana, New York, North Dakota, Oklahoma, South Carolina, Vermont, Washington, Wyoming and Michigan have similar restrictions, with the typical 30-day veterinarian certificate replaced by a 5- to 10- day veterinarian certificate. Nebraska is requiring a permit, and a 48-hour inspection with a veterinarian statement. New Jersey is requiring a 14-day quarantine with a permit for animals coming from states with VS. At this point, reviewing a state’s rules is highly recommended before any animal movement across state borders.
Some countries have also added restrictions. Canada has prohibited the import of animals from states with confirmed VS. Horses can move out of the state and be certified for export after 21 days.
South Korea is prohibiting any horses from a region or state where outbreaks have occurred within 2 years of shipping.
The outbreak has the show community concerned about events, with county and state fairs in full swing, but CDA said that the events don’t need to be canceled.
“The Colorado Department of Agriculture is not recommending events be canceled; instead, we are recommending that events and livestock owners take extra caution to control flies,” said State Veterinarian, Dr. Keith Roehr. “Livestock, including horse and cattle owners, should be aware that insect control is an important tool in the prevention of VS. Most of the cases we have investigated involve horses that have had no history of movement; therefore, controlling black flies and midges are very important in the prevention of the spread of disease.”
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 with clinical signs of VS are isolated until they are healed and determined to be of no further threat for disease spread, typically a minimum of 21 days. There are no USDAapproved vaccines for VS.
While rare, human cases of VS can occur, usually among those who handle infected animals. VS in humans can cause flu-like symptoms and only rarely includes lesions or blisters.
Vesicular Stomatitis (VS) signs and transmission
VS susceptible species include 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, ears, teats, groin area, and above the hooves of susceptible livestock. Vesicles are usually only seen early in the course of the disease. The transmission of vesicular stomatitis is not completely understood but components include insect vectors, me chanical transmission and livestock movement.
“Livestock owners should try to limit exposure of their animals to biting flies,” said Dr. Dee Ellis, the Texas State Veterinarian. “Sand flies and black flies play a role in the virus transmission, so controlling insects is important.”
Tips for event organizers and 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.
• 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/ag/animals and click on “Import Requirements.”
• Fairs, livestock exhibitions and rodeos may institute new entry requirements based on the extent and severity of the current VS outbreak. Certifi cates of Veterinary Inspection issued within 2-5 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, contact the USDA Animal and Plant Health Inspection Service for any new restrictions.
Important points for veterinarians
• Any vesicular disease of livestock is reportable to the State Veterinarian’s Office.
• Since VS is considered a foreign animal disease, any case with clinical signs consistent with VS will warrant an investigation by a state or federal foreign animal disease diagnostician (FADD).
• When VS is suspected, the FADD will gather the epidemiological information, take the necessary blood samples, collect the necessary fluid or tissue from the lesions, and inform the owners and the referring veterinarian as to necessary bio-security and movement restrictions. — Traci Eatherton, WLJ Editor