If you are around horses a lot and you notice drooling or blisters on the mouth, be alert and contact your vet.
A nasty equine virus, vesicular stomatitis (VSV), is going around the Valley.
Although less than a dozen animals here have been involved so far, it is worthwhile to pay attention. Generally, biting flies are the culprits as they transmit the disease from animal to animal. The time from exposure until the first signs appear ranges from two to eight days.
This disease is not strictly limited to horses. Cattle, donkeys, mules and swine can be affected. Sheep and goats are resistant and rarely show signs of the disease.
The virus causes blister-like sores on the mouths, lips, tongues, ears or feet of infected animals. The signs of this disease mimic three other important animal diseases: foot and mouth disease, swine vesicular disease and vesicular exanthema of swine.
Chuck Maker, D.V.M., of Alpine Equine Hospital, explained VSV comes to the Valley from Southeastern Colorado every two to five years. This year, Maker noted, he has seen approximately six to eight infected horses. When Maker confirms the diagnosis by blood and swab tests, he must report the incident to the Animal Health Division, Colorado Department of Agriculture which then quarantines the entire property for at least 14 days.
The disease, he said, usually runs its course in 14 to 21 days. Although the mortality rate is very low, “It can be fatal if it affects the animal’s feet.”
Horses may have trouble eating and drinking as the disease can cause mouth lesions. Veterinarians recommend feeding wet hay and softened grain. When cattle come down with the virus, it can have a negative economic impact for ranchers, but there is no danger in eating the meat, Maker said, adding he hadn’t seen the disease in cattle this year..
The American Association of Equine Practitioners (AAEP) recommends anti-inflammatory medications may be used as supportive care help to minimize swelling and pain so a horse will continue to eat and drink. If the horse becomes dehydrated from not drinking enough water, a veterinarian may need to use intravenous fluids.
Secondary bacterial infection of ulcerated areas is another concern. If fever, swelling, inflammation or pus develops around the sores, treatment with antibiotics may be required.
Holly McClain, owner of Rumble Ridge in Missouri Heights, said that her ranch practices aggressive fly prevention and hasn’t had any disease outbreaks. Liquid and sticky fly traps, fly masks and fly sprays help control fly populations. At the small, private boarding facility McClain additionally applies furazone ointment to the animals’ ears.
Unfortunately, the disease can be transmitted through saliva or polluted water.
Darlene Woodward and Martha Collison, owners of the reining horse operation Skyline Ranch in Carbondale, reported that they too implement regular fly prevention protocols.
Woodward said, “We know that flies can travel many miles between ranches, so we need to be vigilant. We are glad that at our none of our animals have been infected.”
But hold on — humans can catch VSV from handling infected animals. In affected people it causes a flu-like illness with symptoms of fever, muscle aches, headache and weakness. Rarely, humans can get oral blisters similar to cold sores. Recovery usually takes four to seven days.
Gloves, masks and frequent hand washing help prevent any spread.
Colorado horse shows, rodeos and local county fairs may accelerate the spread of VSV as horses travel from many different locations — and some have been canceled in the wake of the disease.
Colorado has seen a total of 667 cases in 2019. Garfield County had five, Eagle had one and Pitkin had none. Elsewhere in the state, the highest numbers were Larimer with 142, Weld with 73 and La Plata with 66. Maker was hopeful that the coming colder weather will minimize and eliminate fly swarms.
All experts strongly insist on staying vigilant. As Rachel Corbman, operations manager, Colorado Horse Rescue, said, “You hate to see your animal get sick, especially when it’s nothing you have control over.”