What The Muck Is That? Vesicular Stomatitis

Even seasoned equestrians are sometimes baffled by horse ailments and eccentricities. Each week we investigate one such conundrum. This week: vesicular stomatitis.

As of July 26, 35 horses in Texas and Colorado are positive for vesicular stomatitis.

“The latest update from the Animal and Plant Health Inspection Service (APHIS), a division of the US Department of Agriculture, said that, in total, 44 horses have been affected since the outbreak began in Texas on July 18, some of which have recovered and their properties released from quarantine.” — horsetalk.co.nz

So what the muck is vesicular stomatitis and how can we protect our horses?

Merck Manual explains the symptoms:

Vesiculation, ulceration, and erosion of the oral and nasal mucosa and epithelial surface of the tongue, coronary bands, and teats are typically seen in clinical cases, along with crusting lesions of the muzzle, ventral abdomen, and sheath.”

In layman’s terms… the disease causes really nasty sores and blisters.

Colorado Disaster Help reads,

VS is transmitted from animal to animal through biting insects and by direct contact with infected animals. Saliva from animals with ulcers in their mouth is infectious. Wear gloves when handling infected animals.”

Black flies and sand flies are the most likely culprits, but any blood-feeding nasty is a potential transmitter.

If the blisters have spread to the mouth, the virus can be transmitted through shared feed and water sources.

The incubation period of the disease is 2 to 8 days, followed by a fever.  Loss of appetite (due to mouth lesions) and lameness (due to hoof lesions) are common.

VS is viral and no specific treatment is available.  No vaccines are available in the US.

Cleaning lesions with a mild antiseptic may help prevent secondary bacterial infections.

Prevention steps include: keeping horses indoors during prime insect feeding times, use of insecticides, fly sheets, masks and boots, and pasturing them away from moving water sources such as streams, rivers, and irrigation canals.

VS may cause flu-like symptoms in humans, generally lasting 3 to 5 days.

Have you had personal experience with vesicular stomatitis in horses?  If so, please leave your story in the comments.

Go Riding!