OGDEN – Utah agriculture officials say they contained an outbreak of 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 equine herpesvirus myeloencephalopathy or EHM was confirmed on a Utah horse on March 7th. EHM is a disease of the EHV-1 virus that can be fatal or can cause significant complications and is spread through nasal drops, aerosol drops or through various common areas, including stalls, water or transport vehicles.
State officials did not disclose where the diseased horse was reported out of respect for the horse’s owner, as the horse is kept in a private unit. After further investigation, they found a second horse on the property, which also tested positive for EHM.
State officials said they were not exactly sure how the initially infected horse got sick. The virus can start internally from stress or can spread from horse to horse.
“We really don’t know where this started right now,” Taylor said. “Both horses are doing well. The epidemic is limited to that one facility and we are well over the two-week period that would concern us there.”
The first positive test raised concerns among the state’s horse-owning community, as it attended events at the Golden Spike Event Center in Ogden on February 20 and just before the horse owner noticed that the horse showed signs of EHM.
Meanwhile, Taylor said there were rumors floating around that a horse had died from the spread of the virus. He said he also began receiving phone calls on March 10 from the horse owners, who said their horses showed signs of the virus.
As a precaution, the state had scheduled a barrel race for the Golden Spike Event Center, canceled that week. The event center posted on social media on March 11 that it will not hold events until a week later, as a precaution, which meant that more than half a dozen events were canceled.
It allowed the state Department of Agriculture to further investigate the situation. The department has identified six facilities with possible sick horses.
In a public letter about Monday’s situation, Taylor wrote that the only premise that came back positive was “initially positive premises.” No other horses were confirmed 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 at our headquarters.
Posted by Golden Spike Event Center on Monday, March 22, 2021
“Currently, this outbreak seems to be contained,” the letter reads. “There have been no additional cases from any event at the Golden Spike Event Center and now we are past the period where we would expect to see cases.”
The letter also says the agency did not believe it was “necessary to restrict equine events in the future”.
He also told KSL.com on Tuesday that there was a dead horse, but the state failed to perform any laboratory work on the horse to confirm the virus, nor were there any connections between the horse and the initially infected horse.
Taylor said the facility with the two infected horses had “done an excellent job” in quarantine since the initial diagnosis. The facility is also close to completing a 21-day precautionary quarantine.
In addition, he praised Weber County’s policy of disinfecting the event center after each event, as it probably considered why the disease was found at only one site.
“Once the horse was there (February 20), the entire facility had been disinfected before the next event,” he said. “So, in retrospect, it was probably very beneficial in containing this disease.”
As for EHM itself, it is treated with supportive care, such as providing fluids and anti-inflammatory agents. The state has distributed a brochure on how horse owners can cope with EHV-1 and EHM after its last possible outbreak in 2019.