On Dec. 5, Oklahoma Department of Agriculture, Food and Forestry (ODAFF) officials released the equine herpesvirus-1 (EHV-1) quarantine placed on the first affected barn at Remington Park racetrack in Oklahoma County. Horses in this barn completed the 14-day restriction without exposure to any EHV-1 positive horses and without showing clinical signs of EHV-1 or fevers. They also tested negative for the virus, with tests one week apart.

In the second of two quarantined barns, one additional horse tested positive by polymerase chain reaction (PCR) and was moved to an isolation facility.

The first horse that tested positive, a 3-year-old Thoroughbred mare, was euthanized Nov. 12 due to the severity of her clinical signs of the neurologic form of EHV-1. At that time, 66 horses in her barn were placed under quarantine.

On Nov. 21, ODAFF confirmed two additional horses with EHV-1 positive tests: one in the index case’s barn and one in a second barn, where 100 horses were exposed and placed under quarantine