The Kentucky State Veterinarian’s Office has placed a barn at Turfway Park, in Florence, under quarantine after a horse previously stabled there tested positive for equine herpesvirus-1 (EHV-1), the office announced on Jan. 21.

“The horse, a 2014 Thoroughbred filly, had been stabled in the barn at Turfway from Oct. 30, 2016, through Jan. 19, 2017,” said E.S. “Rusty” Ford, equine programs manager for Kentucky State Veterinarian Robert Stout, DVM, in a written statement. “The sample, a nasal swab, was collected as the filly was being moved to a private facility to prepare for breeding in 2017. The filly is currently in isolation offsite on a private farm.”

In response, the State Veterinarian’s Office issued a directive on Jan. 20, that horses in the affected barn be confined to the barn, and an official order of quarantine was issued on the morning of Jan. 21.

“Security is in place, with only essential personnel granted access to the barn and caution being taken on exit to ensure sanitation,” Ford’s statement said. “Results of (further) testing are expected to be available Monday evening, Jan. 23. In the interim, horses are confined to the barn. After the risk is better defined, the (State Veterinarian’s) Office will develop schedules to allow eligible horses in the barn to work on the track outside normal training hours after all other horses have returned to their barns.”

Ford was on the grounds on Jan. 21 to meet with trainers in the quarantined barn, track management, attending veterinarians, and racing officials.

“Because proactive measures were implemented at Turfway Park earlier in the meet, including restricted access and controlled movement of horses onto the backside and the elevated biosecurity implemented in all common areas, we are optimistic our efforts will pay a dividend and that we have minimized risk of disease transmission on the backside,” he said.

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Ford said that movement records of horses arriving at and leaving Turfway “have preliminarily identified a potential point of exposure involving two barns at the Keeneland training center. Each of those barns also has been placed under quarantine, and arrangements are being made to sample those horses. As at Turfway, in the interim horses in those barns are restricted to their barn areas and not permitted to train. As our epidemiology investigation continues, we will be better able to define what direct and indirect exposure may have occurred and adjust our strategies as needed.

“As in the past, Kentucky horsemen, tracks, and racing officials recognize and appreciate efforts made to control disease transmission and accept the short-term inconvenience and associated cost for the long-term benefit of racing in the Commonwealth,” he said.

Herpesvirus is highly contagious among horses and can cause a variety of ailments in equids, including rhinopneumonitis (a respiratory disease usually found in young horses), abortion in broodmares, and myeloencephalopathy (the neurologic form). In many horses, fever is the only sign of EHV-1 infection, which can go undetected.

In addition to fever, other common signs of EHV-1 infection in young horses include cough, decreased appetite, depression, and a nasal discharge. Pregnant mares typically show no signs of infection before they abort, and abortions usually occur late in gestation (around eight months), but can be earlier. Abortions can occur anywhere from two weeks to several months following infection with EHV-1.

Horses with the neurologic form usually have a fever at the onset of the disease and might show signs of a respiratory infection. A few days later, neurologic signs such as ataxia (incoordination), weakness or paralysis of the fore- and hind limbs, urine retention and dribbling, loss of tail tone, and recumbency (inability to rise) develop.