Two Deschutes County horses contracted Equine Herpevirus or EHV-1 while attending separate events in Eugene.
“This virus feels like it’s becoming a little bit more transmissible than what it used to, so we have to be on a little higher alert for biosecurity,” said Doctor of Veterinary Medicine at the Bend Equine Medical Center Wendy Krebs.
The first horse tested positive on May 4th and the second May 16th.
“Could certainly have been horses that they contacted there at the show or it could have been horses here in Deschutes County,” said Krebs. “We don’t know of any commonality in the two horses that were here being exposed to each other. So, It’s unknown at this point.”
Krebs says the EHV-1 virus is not uncommon, but things turn much worse if horses contract a more rare Neurological variant called EHM.
EHM stands for Equine Herpevirus Myeloencephalopathy and so that essentially means a disease of the brain and spinal cord caused by the EHM and it does that specifically by forming micro blood clots to the circulation of those structures and so it impairs their functionality,” said Krebs.
The two horses were both humanely euthanized and both ranches are currently under quarantine, which lasts a minimum of 28 days.
The virus is mainly transmitted between horses through sneezing and coughing.
“It can persist in the environment for up to seven days, sometimes even longer under ideal conditions and so we do worry about it being a pretty darn infectious one unfortunately,” Krebs added.
Krebs says several horse shows here in Deschutes County have been canceled out of an abundance of caution and with larger events, like rodeos starting soon, the virus will be monitored closely.
“So, we don’t know of it bridging over to the rodeo horse population at this point and hopefully it will not go there, but we will see what the next couple of weeks brings and if it does start to spread more widely, that might be a consideration,” she said. “I certainly hope not.”
Horse owners are being advised to be cautious themselves.
“I think it is a good time to be prudent and keep your horse home for a little bit until we know the full extent of what this outbreak may or may become,” said Krebs.
More information can be found on the Bend Equine Medical Center Facebook page.
You can read the full statement by the Bend Equine Medical Center here:
According to the Oregon State Veterinarian’s office, equine herpesvirus myeloencephalopathy (EHM) has been confirmed in two Deschutes County horses. EHM is the neurologic form of equine herpesvirus-1 (EHV-1). Both horses have been euthanized.
The deceased horses were not under the care of Bend Equine Medical Center; however, we’d like to share the following statement from the Oregon State Veterinarian, Dr. Ryan Scholz:
“A horse from Deschutes County tested positive for Equine Herpesvirus (EHV-1) on May 4, 2022. Confirmation came from an out-of-state laboratory. The horse had recently attended the Oregon Horse Center at the Prairie Arena in Eugene from April 22-25. The horse has not attended any other events since that time. EHV-1 can cause upper-respiratory disease, neurological disease, abortions, and/or neonatal death. This horse showed neurological symptoms but did not show signs of nasal discharge or an elevated temperature. Unfortunately, due to delayed reporting, this case was only recently shared with the department.
A second horse from Deschutes County became symptomatic on May 13. The infected horse attended a show on May 6-7, also at the Oregon Horse Center in Eugene. Confirmation of EHV-1 came from the Oregon State University Oregon Veterinary Diagnostic Laboratory on May 16.
Both horses were humanely euthanized and both ranches are currently under quarantine. The required quarantine will last a minimum of 28 days.
Equine herpesvirus information:
The EHV-1 virus is highly contagious and is spread via aerosolized secretions from infected coughing horses, by direct and indirect contact with nasal secretions, and fetal fluids. EHV-1 typically has an incubation period of 2-10 days. Respiratory shedding of the virus generally occurs for 7-10 days but may persist longer in infected horses.
Following basic biosecurity practices is an important factor in reducing risk of exposure to all contagious equine diseases. Basic biosecurity measures to follow to decrease potential disease spread at equine events include:
- Limit horse-to-horse contact.
- Limit horse-to-human-to-horse contact.
- Avoid use of communal water sources.
- Avoid sharing of equipment unless thoroughly cleaned and disinfected between uses.
- Monitor your horse for clinical signs of disease and report any temperature over 102°F to a veterinarian.”