Missouri state veterinarian Dr. Steve Strubberg announced July 14 the state’s first case of vesicular stomatitis (VS) in a horse in Newton County in the far southwestern corner of Missouri.

The announcement follows a positive confirmation from the U.S. Department of Agriculture’s National Veterinary Services Laboratory, making Missouri the seventh state to confirm the virus this year. As a result, the Missouri Department of Agriculture is urging horse owners to monitor their livestock closely and call their veterinarian if symptoms arise.

According to the Missouri Department of Agriculture, all susceptible animals on the affected premises have been quarantined. The quarantine will continue for at least 14 days after the onset of lesions in the last affected animal. The department has begun epidemiological work to trace back any possible sources of transmission; however, flies and midges are known to be vectors of the virus.

The July 13 VS situation report from USDA's Animal & Plant Health Inspection Service (APHIS) noted that the Missouri premises housed nine horses, three of which were showing VS symptoms. There are no other susceptible animals at the location, APHIS said.

VS has also been confirmed this year in Arizona, Kansas, Nebraska, New Mexico, Oklahoma and Texas in both horses and cattle (Maps). Many affected premises have been released from quarantine.

As a preventive measure, Missouri is requiring a veterinary examination, Certificate of Veterinary Inspection (CVI) and entry permit for hooved animals entering the state from affected areas.

VS is a contagious, non-fatal virus that primarily affects horses and cattle by causing a fever and vesicular lesions in the mouth, on ears, near the coronary band of hooves or on teats. VS is a reportable disease. To learn more about VS, click here. To view USDA’s latest situation report on the spread of the virus in 2020, visit APHIS online.

In 2019, a large outbreak of VS affected multiple western states, but Missouri did not report any cases.