||TAHC Update: Nation's First Case of Vesicular
Stomatitis (VS) for 2009 Detected in Texas
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 U.S. 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 include horses, cattle, sheep,
pigs, deer and some other species of animals.
“The most recent outbreak was in 2006 limited to Wyoming only, where
17 horses and a dozen cattle on 13 premises were confirmed to have the
virus,” said Dr. Bob Hillman, Texas’ state veterinarian and
head of the Texas Animal Health Commission (TAHC), the state’s livestock
and poultry health regulatory agency. “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. Call the state or country of destination
before moving livestock, 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 cloven-hooved 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
“Move sick animals away from the remainder of the herd to protect
against disease spread,” urged Dr. Hillman. “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 800-550-8242.
Laboratory testing to confirm infection can be run at no charge to the
“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,” said Dr. Hillman. Treatment of VS-infected
animals consists of supportive care, and 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 herd mates 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. Before the 2004 outbreak,
VS had been “silent” since 1998, when Arizona, Colorado, New
Mexico and Texas had cases.
More information about VS and a map showing the location of Starr County
in Texas are available on the TAHC web site at: http://www.tahc.state.tx.us.