November 25, 2025 |
Photo – Bigfoot 99 File Photo
The Wyoming Livestock Board is urging residents to quarantine their horses amid a deadly virus outbreak.
Earlier this month, the Wyoming Livestock Board confirmed that a horse from Colorado tested positive for EHV-1, or equine herpesvirus type one. According to a written statement from the Livestock Board, between November 15th and 20th, the sick animal traveled to events in Cheyenne, Wheatland, Casper, and finally Waco, Texas.
Speaking to Bigfoot99, Wyoming State Veterinarian Dr. Hallie Hasel explained that the source of the EHV‑1 virus can be difficult to determine. However, Dr. Hasel said that the outbreak most likely began at the Texas event or a separate Oklahoma barrel race.
Dr. Hasel said while EHV‑1 was confirmed during both events, most of the cases originated from the Women’s Professional Rodeo Association World Finals in Texas.
The State Veterinarian explained that the equine herpesvirus has two serious variants, type one and type four. Dr. Hasel said EHV‑4 is primarily a respiratory disease, while EHV‑1 is a more serious, potentially deadly condition that can infect animals without obvious symptoms.
Equine herpesviruses may sometimes hide inside nerve cells, remaining latent for the entire lifespan of the horse. Stress, illness, or transport can reactivate the virus.
Dr. Hasel said EHV‑1 is highly contagious, spreading through direct contact between animals, shared food and water, and contaminated clothing or equipment.
The incubation period for equine herpesvirus type one is typically between two to 10 days after exposure. Dr. Hasel explained that infected animals may exhibit a fever, runny nose, difficulty walking, and general lethargy.
If you suspect your horse has been exposed to EHV‑1, Dr. Hasel advised taking its temperature twice daily for two weeks. If the reading is above normal, quarantine the animal and contact a veterinarian immediately.
According to the American Association of Equine Practitioners, 10 to 20 percent of infected horses may develop the neurological form of EHV‑1, which can be fatal. There is no cure. Treatment involves isolation, anti‑inflammatories, and fluids. Vaccines may help limit the spread of equine herpesvirus, but they do not prevent horses from contracting the neurological form.
In Wyoming, veterinarians are required to report any neurological diseases to the state Livestock Board. Horses that test positive for EHV-1 must be quarantined for at least 21 days.
To help slow the spread of the disease, Dr. Hasel urged all horse owners, even those whose animals show no signs of illness, not to attend any equine events unless absolutely necessary, especially if it has a fever.
At the time of this report, the Wyoming Livestock Board has not confirmed any cases of EHV‑1 in the state.
If your horse recently traveled to Texas or Oklahoma, contact the Wyoming Livestock Board immediately at 777‑7515 for guidance on isolation and monitoring.
