VSV is in Ouray County. (Photo by Leslie Vreeland/The Watch)

Carla Reams didn’t carry a flag at the San Miguel Basin Rodeo this year.

A lifelong Nucla resident, Reams hails from a rodeo family. For years, she has saddled up for the rodeo to make laps around the arena on one of her horses with a sponsor flag in tow — if she wasn’t competing in the rodeo herself.

With vesicular stomatitis prevalent in Colorado, though, and with cases hitting as close to home as Montrose County earlier this summer, Reams said she didn’t want to chance her horse coming down with the dreaded virus. Instead, she sat in the grandstands and watched the rodeo as a spectator.

“I didn’t really want to put any of my horses at risk,” she said.

Other local moms whose children rode in the San Miguel Basin Junior Rodeo said they worried during the July 26 event, even while fly-spraying their kids’ equines thoroughly and keeping them away from other horses on site.

Some of the same rodeo moms said they wouldn’t be traveling to other county rodeos on the Western Slope this year. The belt buckles and prizes just weren’t worth the risk.


Vesicular stomatitis virus, known as VSV, is a viral disease that causes blisters and ulcers on the mouth, feet, ears and udders of cattle, horses and swine, and occasionally mules, donkeys, sheep, goats, llamas and alpacas, the state veterinarian’s office said.

Believe it or not, VSV is actually not considered a highly contagious virus, as it is spread primarily through insect vectors, and seldomly through saliva or other contact. It is rarely fatal. Still, it is quite worrisome to livestock owners.

Clinical signs include vesicles, or sacs of fluid, and erosions and sloughing of the skin on the muzzle, tongue, ears, teats and coronary bands (the area where an animal’s hairline meets its hoof). Excessive salivation is often the first sign of the disease, along with a reluctance to eat or drink. Lameness and weight loss may follow, side effects of the virus that are no doubt terrifying to those who own horses.

The incubation period ranges from two to eight days, so horses that contract the virus show signs of it fairly quickly.


Contrary to an Associated Press news brief published earlier this month, the disease is not “rabies-like.” That misinformation might have unnecessarily alarmed some livestock owners.

Rabies is a viral disease that affects the central nervous system of mammals and has an extremely high case fatality rate. Experts say the rabies virus is from the genus Lyssavirus, but VSV is from the genus Vesiculovirus.

The AP story has been since corrected, and the state’s Department of Agriculture said, “It is highly misleading to say that vesicular stomatitis virus is a rabies-like virus. Both viruses belong to the same family, Rhabdoviridae, but that classification is based on viral structure alone.”

Maggie Baldwin, epidemiology traceability veterinarian for the Colorado Department of Agriculture (CDA) added, “The two diseases have no similarities in transmission, clinical signs or outcome.”

Humans don’t have to worry too much about getting it, either. In rare cases, it’s possible that people may become infected with VSV when handling affected animals, but that doesn’t usually happen, experts say. Still, it’s recommended that individuals use personal protective measures when handling infected animals.


The first case of VSV this summer was reported July 3 in Weld County.

In late July, officials from the Dolores County Rodeo cancelled the annual event because the virus was showing up in the area. They were worried the disease would spread during the rodeo.

As of Aug. 2, the disease was confirmed in 14 Colorado counties, including Adams, Archuleta, Boulder, Broomfield, Conejos, Delta, Jefferson, La Plata, Larimer, Mesa, Montezuma, Montrose, Morgan and Weld.

As of last week, the CDA has confirmed additional cases of VSV in the counties of Alamosa, Arapahoe, Douglas, Gilpin, Grand, Mineral and Ouray, too.

It’s in 21 Colorado counties now, and many believe San Miguel County is probably next.

There are more than 250 infected animals statewide in quarantine, while approximately 277 that have been released from quarantine.

So far, all cases are equine, with the exception of one bovine case in Delta County and another in Boulder County.

The CDA is updating its website in order to provide accurate information and resources on VSV weekly (

A map of infected counties is also on the website, so people can plan travel accordingly.


Because there is no vaccine for VSV, experts believe the best prevention lies in dealing with flies. This means fly-spraying livestock animals and also staying on top of manure maintenance, since flies are attracted to dirty pens and pastures, and multiply quickly.

The state veterinarian’s office also says to avoid sharing feed, cleaning and health tools with livestock for the time being, and to weigh the risks of transporting horses to destinations where VSV may be more active.

The state vet’s office requests that all cases be reported. Animals that test positive for VSV must remain in quarantine for roughly a month.

“It is of utmost importance that livestock owners report VS occurrences and comply with hold or quarantine orders to limit the potential for disease spread in this VS outbreak,” Dr. Keith Roehr, the Colorado state veterinarian, has said in multiple press releases.  


Liz Foley of Norwood said she’d still travel with her horse at this point, adding she’ll be sure to check for outbreaks of VSV and where they’re located before going anywhere.

“Yes, I would travel with my horses and exercise appropriate caution for competitions in nearby counties that have reported cases,” she said.

On the other hand, the managers of the El Prado horse boarding facility in Telluride are a little more worried about the spread and potential infection of their herd. In fact, they issued a statement to their boarders last week mandating that any horse leaving their Wilson Mesa facility and traveling to an infected county for competition or for any other reason wouldn’t be allowed back onto the property.

Officials at El Prado said they can’t afford to take a chance.

Most horse shows, including the Colorado Reined Cowhorse Association show Sept. 19-22 in the new Montrose Event Center, are requiring a vet check at least two days before entering the show premises. Their show will still go on, at least for those who have the right paperwork in order for competition.

Other horse shows in Colorado are requesting a health certificate at least five days in advance of competitions.

Those traveling out of state for shows, competitions or to sell animals may run into trouble, though. Colorado vets and livestock owners are supposed to contact any “state of destination” to let officials know they’re coming from another state affected by VSV.


Many on the Western Slope agree that it’s been a good water year. As a result, the bugs have been bad. The flies will last until the fall, when cooler temperatures arrive. That means VSV will linger and spread until then.

Since VSV is a virus that appears annually, it will come back again.

Carl Wood, owner and operator of Double Tree Horse Farm in Delta County, has worked in the horse business for decades. His farm houses up to 30 horses at a time for breeding, training and boarding purposes. No doubt, over the years he’s seen bad “bug years” and his share of disease outbreaks in equine populations. Wood said he thinks people need to “calm down” about VSV.

“People get too worried about it,” he said this week. “Fly spray your horses. Don’t let them drink after other horses, and keep a distance from other horses when at events.

“I’ve seen it this bad before, and this, too, will pass.”