Eight additional horses in Remingon Park's second quarantined barn have tested positive for EHV-1. Remington Park is in Oklahoma County. | Photo: Wikimedia Commons

In a Nov. 27 update, officials at the Oklahoma Department of Agriculture, Food and Forestry (ODAFF) confirmed that eight additional horses in Remington Park’s second quarantined barn have tested positive, via polymerase chain reaction (PCR), for equine herpesvirus-1 (EHV-1). The positive horses, which are clinically normal (not showing any signs of illness), were moved to the isolation barn. The index case remains the only horse to develop neurologic signs. Remington Park is in Oklahoma County.

Following the index case, a 3-year-old filly, and the subsequent isolation of 66 horses exposed in the filly’s barn, ODAFF officials announced on Nov. 21 that two additional horses—one in the index case’s barn and one from another barn—tested positive for EHV-1. Officials reported that 100 horses in the second barn were subsequently quarantined.

Following these confirmations, officials in New Mexico and Kentucky restricted horses from Remington Park from entering racetracks in their states