No Additional Signs of EHV-1 at Fair Hill

The horse quarantined with a suspect case of equine herpesvirus-1 (EHV-1) at the Fair Hill Training Center, in Elkton, Md., will be retested next week, according to a statement from Kathleen Anderson, DVM, owner and manager of the Elkton-based Equine Veterinary Care, PC.

"The isolated suspect horse continues to be stable with gradual improvement of neurologic status," Anderson relayed. Because the laboratories will be closed in observance of Martin Luther King Jr. Day on Jan. 20, the horse will be retested for the disease on Tuesday, Jan. 21, she said.

Meanwhile, a group of exposed horses currently in an isolated barn remain free of clinical signs of disease and elevated temperature, she relayed.

"The last day of isolation barring any unforeseen changes will be Wednesday, Jan. 22 for this group," Anderson said.

Earlier this month, the suspect horse exhibited an elevated temperature prior to a colic episode and subsequent moderate neurologic signs, Anderson told The Horse on Jan. 13. The horse tested negative on serology for equine protozoal myeloencephalitis, she said, and was also tested for EHV-1. Anderson said both “buffy coat” (a type of blood test) and nasal swab samples on the isolated horse were sent to both the Maryland Department of Agriculture and the University of Kentucky Veterinary Diagnostic Laboratory. The buffy coat samples were negative; however, the PCR nasal swab sample demonstrated a weak positive with no evidence of neuropathogenic strain mutation. 

Although it's not transmissible to humans, EHV-1 is highly contagious among horses and camelids and is generally passed from horse to horse via aerosol transmission (when affected animals sneeze/cough) and contact with nasal secretions on objects such as feed buckets, grooming supplies, humans, and other infected animals. The disease can cause a variety of ailments in equids, including rhinopneumonitis (a respiratory disease usually found in young horses), abortion in broodmares, and myeloencephalopathy (EHM, the neurologic form).

Video: Health Alert: Equine Herpesvirus (EHV)

Myeloencephalopathy is characterized by fever, ataxia (incoordination), weakness or paralysis of the hind limbs, and incontinence. Should a horse that potentially has been exposed to EHV-1 display any of the aforementioned clinical signs, call a veterinarian to obtain samples and test for the disease. will continue to provide updates as more information becomes available.

Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.