OGDEN – Utah farm officials say they believe they contained an outbreak of a serious horse disease, which was confirmed in the state earlier this month after the sick horse attended an event in Weber County.
Dr. Dean Taylor, the state veterinarian, said that equine herpesvirus myeloencephalopathy, or MHE, was confirmed on a horse in Utah on March 7. HEM is a disease of the EHV-1 virus that can be fatal or create significant complications and spread through nasal droplets, aerosol droplets or several shared spaces, including bays, water or transport vehicles.
State officials did not disclose where in the state the sick horse was reported out of respect for the horse’s owner, because the horse is kept in a private facility. After further investigation, they found a second horse on the property that also tested positive for MHE.
State officials said they were not sure how the horse originally infected fell ill. The virus can start internally from stress or spread from horse to horse.
“We really don’t know where it started at this point,” said Taylor. “Both horses are doing well. The outbreak is confined to that facility, and we are well beyond the two-week period that we would be concerned about.”
The first positive test raised concerns within the state’s horse-owning community because she attended events at the Golden Spike Events Center in Ogden on February 20 and just before the horse owner noticed that the horse was showing signs of EHM.
Meanwhile, Taylor said there were also rumors that a horse died due to the spread of the virus. He said he also started receiving calls on March 10 from concerned horse owners, who said their horses were showing signs of the virus.
As a precaution, the state had a barrel race scheduled for the Golden Spike Event Center canceled that week. The event center posted on social media on March 11 that it would not hold an event until a week later, just in case, which meant that more than half a dozen events were canceled.
This allowed the state’s Department of Agriculture to further investigate the situation. The department identified six facilities with possibly sick horses.
In a public letter on the situation on Monday, Taylor wrote that the only assumption that was positive was the “originally positive assumptions”. No other horse has been confirmed to be sick with the virus, including those that could have been exposed on February 20.
Please see the letter below with an update on EHV-1 in our facilities.
Posted by the Golden Spike Event Center on Monday, March 22, 2021
“Currently, this outbreak appears to be contained,” says the letter. “No additional cases have arisen from any event at the Golden Spike Event Center and we are now past the period when we expected to see cases.”
The letter also says that the agency does not believe it is “necessary to restrict equine events in the future”.
He also told KSL.com on Tuesday that there was a deceased horse, but the state was unable to do any laboratory work on the horse to confirm the virus, nor was there any connection that linked that horse to the originally infected horse.
Taylor said the facility with the two infected horses “did an excellent job” by quarantining their horses since the original diagnosis. The facility is also close to completing a 21-day precaution quarantine.
In addition, he praised the policy of Weber County to disinfect the event center after each event, because it probably took into account the reason why the disease was only found in one location.
“Once that horse was there (February 20), the entire facility was disinfected before the next event,” he said. “So this was probably, in hindsight, very beneficial in containing the disease.”
The HEM itself is treated with supportive care, such as the supply of fluids and anti-inflammatories. The state shared a leaflet on how horse owners can cope with EHV-1 and EHM after their last possible outbreak in 2019.