UPDATE: State Veterinarian Dr. Brent Robbins placed all of New Orleans Fair Grounds under quarantine Thursday afternoon in an effort to contain the deadly equine herpes virus.

“This quarantine is being implemented out of an abundance of caution as we work to contain the disease,” he said. “While there has been restricted movement of horses at the racetrack, at this point, we cannot risk horses possibly leaving the Fair Grounds while some are still testing positive for the virus.”

As of Thursday, nine horses remained in isolation.

NEW ORLEANS (WGNO) – The state Department of Agriculture and Forestry has placed restrictions on horses at the New Orleans Fair Grounds after a 2-year-old horse tested positive for a highly contagious and often deadly illness.

The horse, a thoroughbred gelding horse, developed a fever and neurological signs of the virus last month. The horse was euthanized Dec. 26. It tested positive for Equine Herpes Myeloencephalopathy.

Of the 49 barns at Fair Grounds, three are quarantined because horses showed symptoms of the virus. Three horses are in isolation and under close observation.

The LDAF says restricted movement means no horses are allowed in or out of the Fair Grounds property unless authorized by the Racing Commission or the state veterinarian.

“This is a very fluid situation at this time. Because the disease is highly contagious, we are doing everything possible to keep the situation contained,” said Louisiana Agriculture Commissioner Mike Strain.

EHM is caused from a mutated strain of a common respiratory virus EHV-1. Although not transmissible to humans, EHM is a severe, often deadly, transmissible neurological disease that is spread most commonly by direct horse-to-horse contact. The virus also can be spread through the air, contaminated equipment, clothing and hands.

Symptoms of the disease include fever, ocular or nasal discharge, limb swelling, abortion and neurologic signs such as unsteady gait, urine dribbling, hind limb weakness and inability to rise. There is no cure for the disease, but symptoms may be treatable.

Biosecurity measures at the barn and high traffic areas of the track have been ramped up in response to the confirmed case of EHM. The measures include restricting personnel within the quarantined barns, and hand, boot, and equipment sanitizing stations have been set up.

Horse owners are reminded to be vigilant at events where horses are congregated and should practice preventative measures such as vaccination, hand washing and not sharing equipment. Horse owners should contact their veterinarian for more information.

According to LDAF records, EHM was last detected at the racetrack in 2008.