After a Two-Week Lull, VSV Confirmed in Missouri

Following two weeks of USDA Animal and Plant Health Inspection Services (APHIS) Situation Reports with no new confirmed vesicular stomatitis virus (VSV) cases and all previously positive premises released from quarantine, APHIS confirmed one new positive equine premises, in Texas County, Missouri, in its Oct. 8 report.

Premises with confirmed positive and suspect cases are quarantined and monitored by veterinarians for at least 14 days from the onset of lesions in the last animal affected.

Once APHIS confirms a county as VSV-positive, new equine premises in that county that show clinical signs of VSV aren’t required to be tested. Instead, that premises is quarantined and classified as suspect. Also classified as suspect are premises where animals don’t meet the definition of a confirmed case, but where diagnostic evidence of a recent VSV infection exists.

VS 101

Vesicular stomatitis virus 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 heal in two or three weeks.

Because of the virus’ contagious nature and its resemblance to other diseases such as foot-and-mouth disease, animal health officials urge livestock owners and caretakers to report these symptoms to their veterinarian immediately. Most animals recover with supportive care by a veterinarian.

“Vesicular stomatitis has been confirmed only in the Western Hemisphere,” APHIS said on its website. “It is known to be an endemic disease in the warmer regions of North, Central, and South America, and outbreaks of the disease in other temperate geographic parts of the hemisphere occur sporadically. The Southwestern and Western United States have experienced a number of vesicular stomatitis outbreaks … Outbreaks usually occur during the warmer months, often along waterways.” According to Angela Pelzel McCluskey, DVM, APHIS’ equine epidemiologist, the largest VS outbreak in more than 40 years of recorded history occurred in 2019.

Some states and other countries might restrict movement of, or impose additional requirements for, susceptible animals from states having known VS cases. Before moving livestock, contact the state of destination for its requirements.