The Kentucky Department of Agriculture announced in a statement Oct. 30 that it lifted a quarantine order for half of Barn 47 at Churchill Downs, which was placed under quarantine Oct. 26 because a horse was found to be infected with equine herpes virus (EHV-1).
Sixteen horses trained by Al Stall, Jr. were allowed to return to regular training on Oct. 30 at Churchill Downs after state agriculture officials determined that none were suffering from an active EHV-1 infection and there was a "minimal" opportunity for exposure to the virus. The 40-stall barn is divided by a firewall and the infected horse were all stabled on one side of the wall.
Remaining under quarantine are 19 horses, including one stable pony, trained by David Carroll. A 3-year-old under Carroll's care was the lone horse to test "positive" last week for EHV-1. That horse was moved to a Lexington, Ky. equine hospital after he displayed unusual symptoms on Oct. 25 and was later confirmed to have been infected with EHV-1.
The 19 horses still stabled in Barn 47 have returned "negative" results on nasal and blood tests designed to detect infection by the virus. These horses will be tested again early next week and their status monitored by the state, according to Rusty Ford, equine programs manager for the office of Kentucky State Veterinarian Dr. Robert Stout.
Racing continues uninterrupted for Churchill Downs' 21-day fall meet, which ends Nov. 24. All horses that enter and depart the stable area are required to present documentation that certifies each horse has been healthy for the previous 72 hours. Horses shipping in to compete at Churchill Downs are required to stable in either the receiving or stakes barns, and those barns – along with the starting gate, paddock and equipment used by outriders – are being regularly disinfected.
Equine herpes is a virus, so it can be spread through the air when a horse coughs – although studies on the virus indicate that it is very short-lived and is susceptible to disinfectants. The maximum extent of the airborne transmission of the virus is thought to 35 feet. Horses may also contract the disease if they come in contact with the clothing of a person who has worked with an infected horse, the tack and equipment worn by an infected horse, or a shared food and water source. Symptoms of equine herpes virus most commonly include fever and an upper respiratory infection. In severe cases, horses can suffer a loss of coordination and an inability to stand and, in the worst cases, the illness can be fatal. Agriculture Department officials say the disease poses no danger to humans.