Officials with the California Department of Food and Agriculture are continuing to monitor a recent outbreak of Equine Herpes Myeloencephalopathy (EHV-1)—a deadly virus that affects horses’ nervous systems.
According to information from the department, the disease has been traced to horses that attended the National Cutting Horse Associations’ Western National Championships in Ogden, Utah, April 30 through May 8. Officials are saying California horses that participated in this event could have been exposed to the virus.
The outbreak comes on the eve of the Santa Maria Elks Rodeo, an event at which horses naturally tend to congregate.
“Of course we’re worried about the outbreak because it’s a serious disease,” Elks Rodeo promoter Seth Doulton said, “but the virus is primarily in the horse cutting world.”
Doulton said there is little to no risk of the rodeo being shut down, but the staff intends to be vigilant.
“This week will be very important for us,” he said. “If we go without any new cases, we’ll have dodged that bullet.”
Doulton added he’s heard a lot of misinformation circulating about the disease.
“There’s absolutely no risk of it being passed to humans,” he said.
EHV-1 damages blood vessels in a horse’s brain and spinal cord, thus blocking the flow of blood to tissue and causing limited nervous system function.
As of May 23, there were 18 confirmed cases of EHV-1 in the state. The closest counties with infected horses include Kern, Los Angeles, and Ventura.
Sixteen of the infected horses participated in the horse cutting championship in Utah, and two of the horses participated only in the Kern County Cutting Horse Event on May 13 in Bakersfield. One of the horses had to be euthanized after showing signs of severe neurological damage. All of the remaining horses are currently under state quarantine.
The virus is transmitted to horses through surface contact. Cohabitation with infected horses presents the greatest danger, but the disease can also be transmitted through brushing equipment, tack, and feed. A temperature in excess of 102 degrees Fahrenheit is a common precursor to other symptoms, such as nasal discharge, incoordination, weakness of the hindquarters, and lethargy.
The Department of Food and Agriculture will continue to monitor horses in the western states.
For more information about EHV-1, visit www.cdfa.ca.gov.
This article appears in May 26 – Jun 2, 2011.
