Vesicular Stomatitis (VS), a domestic viral disease that primarily affects horses, cattle and swine, has appeared early this year. Laboratory tests completed April 27 confirmed the infection in two horses on a premises in Grant County, in southwest New Mexico. VS appears sporadically, usually involving New Mexico, Texas, Arizona, Colorado and occasionally, other states. Recent outbreaks occurred in 1995, 1997, 1998 and 2004, with initial cases detected in mid-May or early June. Outbreaks usually end in early winter.

VS outbreaks cause concern among ranchers, because signs mimic those of foot-and-mouth disease (FMD), a highly contagious and dangerous foreign animal disease. VS can cause production losses, because affected livestock may develop blister-like lesions and open sores in the mouth, dental pad, tongue, lips, nostrils, hooves and teats. During the usual two- to three-week healing time, infected animals may be lame, or refuse to eat or drink. Dams may reject their nursing offspring, and dairy cattle can experience a severe drop in milk production.

“VS-infected animals, and all other susceptible livestock on a premises are quarantined until 30 days after all lesions are healed,” said Dr. Dee Ellis, who heads up field operations for the Texas Animal Health Commission (TAHC), the state’s livestock and poultry health regulatory agency. “This ensures that sick animals are not moved, and helps prevent the disease from being spread by direct contact or through contaminated saliva or drainage from sores. Prior to quarantine release, animals are re-examined by a state or federal regulatory veterinarian.”

Dr. Ellis noted that some states place prohibitions or restrictions on livestock moved from VS-affected states. TAHC regulations require livestock from affected states to be accompanied by a valid certificate of veterinary inspection (health paper) on which the accredited veterinarian certifies the animals are not from a quarantined premises.

“We urge livestock owners in Texas to report any signs of VS to their private veterinary practitioner or the TAHC,” commented Dr. Ellis. “History could repeat itself. In 2004, Texas had confirmed cases on 15 premises. In Colorado, VS was detected on 199 ranches, and on 80 sites in New Mexico.”

“A free laboratory test will ensure the animal’s blisters or sores are from VS and not from an introduction of foot-and-mouth disease into the U.S,” urged Dr. Ellis. “If you examine sick animals, wear latex or rubber gloves and practice good hygiene, as VS can be contagious to humans, resulting in short-term flu-like symptoms.”

To report suspected cases of VS, owners and private veterinary practitioners should call their respective state’s livestock health regulatory agency: Texas Animal Health Commission -- 1-800-550-8242 (operational 24 hours a day) New Mexico Livestock Board -- 1-505-841-6161 Colorado Department of Agriculture, State Veterinarians Office -- 1-303-239-4161