Remington Park EHV: 29 Horses Released From Quarantine
Oklahoma Department of Agriculture, Food, and Forestry (ODAFF) has issued an update on the recent equine herpesvirus-1 (EHV-1) outbreak at Remington Park in Oklahoma County. As of Dec. 26, state animal health authorities had released 29 additional horses from quarantine, leaving 30 horses still under quarantine.

The horses released completed two negative EHV tests seven days apart and 14 days with no fevers, no clinical signs compatible with EHV-1, and no exposure to EHV-1-positive horses.

The horses released from quarantine were originally housed in the second quarantine barn but at the conclusion of the race meet were moved to separate barns.

Two additional horses in the second quarantine barn were moved to the isolation barn after they tested positive for EHV-1, bringing the total in isolation to 11. Timely response by Remington Park officials successfully contained the virus in the two initially quarantined barns, and enhanced biosecurity measures and twice-daily temperature monitoring remain in place. ODAFF staff continues to monitor the situation on-site.

EHV 101

Equine 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 equine herpesvirus myeloencephalopathy (EHM, the neurologic form).

In many horses, the first or only sign of EHV-1 infection is fever, 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 EHM 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.

Herpesvirus is easily spread by nose-to-nose or close contact with an infectious horse; sharing contaminated equipment including bits, buckets, and towels; or clothing, hands, or equipment of people who have recently had contact with an infectious horse. Routine biosecurity measures, including hygiene and basic cleaning and disinfection practices, should be in place at all times to help prevent disease spread.

Current EHV-1 vaccines might reduce viral shedding but are not protective against the neurologic form of the disease. Implementing routine biosecurity practices is the best way to minimize viral spread, and the best method of disease control is disease prevention.