EHV-1 being reported across U.S.
The neuropathogenic strain of equine herpesvirus (EHV-1) or equine herpes myeloencephalopathy (EHM) has been reported in Minnesota, Texas, Oklahoma and Virginia in the past few weeks.
Oklahoma State University
Feb. 13, 2015. A hospitalized patient at the Oklahoma State University Veterinary Medical Hospital has been confirmed with the neuropathogenic form of equine herpesvirus (EHV-1). Necessary biosecurity measures have been taken and disinfection protocols have been implemented.
Minnesota Board of Animal Health
A horse with EHM has been identified in Scott County.
The horse was stabled at Dark Horse Farm, Prior Lake, Minnesota. The horse became ill on Friday, Feb. 6. It exhibited neurological signs including ataxia and urinary incontinence. It was then moved to Cleary Lake Veterinary Clinic in Prior Lake where it was held in isolation for treatment until test results were completed. Infection with equine herpesvirus type 1 (EHV-1) was subsequently confirmed by polymerase chain reaction (PCR) tests performed at Cornell University. The horse was euthanized on Thursday, Feb. 12.
The Board has placed a quarantine on the other horses at the stable. These horses will not be allowed to leave the stable for at least 21 days and will be monitored closely for fever or symptom of illness consistent with EHV-1.
A second horse at the facility tested positive for the same strain on Feb. 18.
Texas Animal Health Commission
The Texas Animal Health Commission is investigating two confirmed cases of the equine herpesvirus type-1 (EHV-1) in horses at two different stables in northwestern Galveston County. Laboratory tests conducted on nasal swabs were positive for the neuropathogenic strain of EHV-1. There is no indication of involvement of horses outside of those stabled at the two facilities.
The first confirmed horse showed signs of respiratory illness on Jan. 24 and veterinary care was sought. The affected horse attended the Sand Hills Rodeo in Odessa, Texas, and was on the premises there on Jan. 6-8, then returned home. Prior to death some changes in behavior were present but the usual neurologic symptoms associated with EHV-1 had not developed. The second horse that tested positive for EHV-1 showed a fever and respiratory symptoms and is under close veterinary care. Both stables have been placed under quarantine, and investigation continues.
Virginia Department of Agriculture and Consumer Services
Feb. 5, VDACS was notified of a positive result for Equine Herpesvirus Myeloencephalopathy (EHM) on a horse displaying neurologic signs in western Albemarle County, Northwest of Charlottesville. The affected horse is located at a boarding stable with 14 other horses at the facility. VDACS contacted the stable manager and placed the facility under quarantine – no horses are allowed to exit or enter the premises until the quarantine is released. Initial findings indicate that only one exposed horse from the facility has left the premises within the last 14 days, and that horse went out of state.
On Feb. 12, VDACS learned that a horse from Loudoun County had tested positive for the neuropathogenic strain of EHV-1. The horse is quarantined in the isolation unit at the Marion duPont Scott Equine Medical Center (EMC) where it is recovering. A second horse from the same farm exhibited a fever but no neurological signs. Two horses remain quarantined at the Equine Medical Center and 33 horses are quarantined at the Loudon County farm. No horses have had any neurologic signs. Two horses under quarantine at the farm have had fevers, and testing for EHV-1 is pending for these horses.
The affected Albemarle County horse continues to improve; no additional horses there have shown any signs of disease.