First case of vesicular stomatitis in 2009 detected in south Texas

Jul 10, 2009
by WLJ
First case of vesicular stomatitis in 2009 detected in south Texas

The nation’s first case of vesicular stomatitis (VS) for 2009 has been detected in a horse in Starr County in far south Texas. VS is a sporadically occurring virus that is endemic to the United States. Signs of the disease include blisters, lesions and sloughing of the skin on the muzzles, tongue, teats and above the hooves of susceptible livestock, which includes horses, cattle, sheep, pigs, deer and some other species of animals.

The most recent outbreak, which occurred in 2006, was limited to Wyoming, said Bob Hillman, Texas state veterinarian and head of the Texas Animal Health Commission.

In the 2006 outbreak, 17 horses and a dozen cattle on 13 premises were confirmed to have the virus. “To prevent the spread or introduction of infection, many states and countries will place additional entry requirements or restrictions on the movement of animals from affected states or portions of the state. Before moving livestock, call the state or country of destination to ensure that all entry requirements can be met. Do not risk shipments being turned away or, worse, spreading disease and facing legal action by animal health authorities.

“Often, horses are the signal, or first animals to be confirmed with vesicular stomatitis when the virus is active. If the blisters and lesions are seen in cattle, sheep, pigs or other clovenhooved animals, our first concern is a possible introduction of foot-and-mouth disease, the most costly and destructive foreign animal disease. Horses are not susceptible to foot-and-mouth disease, but anytime blisters or unusual sores are seen, animals should be examined by a veterinarian as soon as possible.

“Move sick animals away from the remainder of the herd to protect against disease spread,” Hillman urged. “Do not move sick animals from the premises, and call your veterinarian or the nearest Texas Animal Health Commission area office, or the Austin headquarters at 1-800- 550-8242. Laboratory testing to confirm infection can be run at no charge to the livestock owner.

“Vesicular stomatitis is painful for affected animals, but usually the lesions will heal within two weeks to a month. For some severe cases, owners may elect to have an infected animal euthanized to put an end to the suffering. In dairies, VS infection can lead to a substantial loss of production,” Hillman said. Treatment of VS-infected animals consists of supportive care. Antibiotics may be needed to prevent secondary infections in the open sores.

Animal health officials in nearly all states, including Texas, require VS-infected animals and their herdmates to be quarantined until at least 21 days after all lesions have healed. A follow-up examination of the animals by the state veterinarian’s office is required prior to quarantine release.

VS outbreaks are extremely sporadic and years may lapse between cases. Sand flies and black flies are thought to play a role in the virus transmission, so controlling insects is important. In 2005, the VS outbreak involved livestock on at least 445 premises in nine states, including Arizona, Colorado, Idaho, Montana, Nebraska, New Mexico, Texas, Utah and Wyoming. In 2004, affected animals were detected in eight counties each in Texas and New Mexico and in 22 Colorado counties. — WLJ