Vesicular stomatitis (VS) has been detected in a horse on a premises in Maricopa County, Arizona. (Maricopa County is located in the south-central portion of the state and is home to Phoenix.) The owner of the five-year-old gelding reported that the animal was purchased about three weeks ago. Sores appeared in the horse's mouth in mid-April, and tests run at the National Veterinary Services Laboratory in Ames, IA, confirmed the infection. Arizona was "spared" in the 2004 VS outbreak, when Texas had 15 cases, New Mexico had 80, and Colorado 199.

One premises in Grant County, New Mexico, remains quarantined where two horses are recovering from the viral blistering disease. Infected and susceptible animals remain under movement prohibition until at least 30 days after all lesions heal, and a state or federal regulatory veterinarian examines the livestock.

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. Lesions usually will heal in two or three weeks. Because the signs of VS mimic those of foot-and-mouth disease (FMD), animal health officials strongly urge livestock owners and caretakers to report potential cases of VS to their private veterinary practitioner or state livestock health officials. Laboratory tests run at no charge to the producer will differentiate whether infection is caused by VS and not FMD, a dreaded foreign animal disease.

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 Veterinarian's Office -- 1-303-239-4161 Arizona Department of Agriculture, State Veterinarian's Office -- 1-602-542-4293

Prior to moving livestock from Arizona or New Mexico, check with the state of destination to ensure all VS testing and inspection requirements have been fulfilled. The Texas Animal Health Commission (TAHC) requires 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. The TAHC web page is at http://www.tahc.state.tx.us.

Kentucky embargoes livestock and wild or exotic animals from counties that include and surround the infected premises, and place strict entry requirements on animals from the remainder of the state, or even other states that share a common border with an infected county. To access specific Kentucky requirements, go to: http://www.kyagr.com/state_vet/ah/vsv_embargo.htm.

Florida animal health officials require susceptible animals coming from VS-affected states to have prior permission for entry and a negative test for VS within 10 days prior to entry. The certificate of veterinary inspection also must include a statement that the animals are free of clinical signs of VS and have not been exposed or located within 10 miles of a positive premises within the previous 30 days. The Florida Department of Agriculture web site is at: http://doacs.state.fl.us/>http://doacs.state.fl.us/.