The Colorado State Veterinarian’s Office is actively monitoring an outbreak of Equine Herpes Virus (EHV-1) in Texas and Oklahoma. EHV-1 is a highly contagious and sometimes fatal virus that can cause a serious neurological disease in horses called Equine Herpes Myeloencephalopathy (EHM).
This outbreak has been connected to horses that participated in or were around barrel racing and rodeo events in Texas and Oklahoma over the past several weeks. Confirmed cases of EHM have been reported in both states, and the investigation into other sick horses is ongoing.
The State Veterinarian’s Office received notification from Oklahoma and Texas identifying horses that traveled to or from these events to Colorado. Contact has been made with these owners and the exposed horses have been put under hold orders with instructions for monitoring.
One of the trace horses from the event in Waco, Texas, spiked a mild fever after returning home to Larimer county. That horse tested positive for EHV-1 on November 20 and that horse and the premises where it resides have been placed under quarantine. The horse initially developed a fever, but is now exhibiting additional neurological signs.