Churchill Downs and Kentucky veterinary officials are segregating horses because of a possible outbreak of an equine respiratory virus in three barns, but no horses entered in Saturday's Preakness Stakes (gr. I) are affected, officials said.The Kentucky Department of Agriculture has placed three barns under quarantine while officials await results of tests to determine if some horses stabled in the barns have been infected with equine herpesvirus. Affected are Barn 6, which houses horses trained by Ronny Werner; 38, which is occupied by Steve Asmussen; and Barn 39, which is home to horses trained by Paul McGee and Bill Cesare.Results of tests on horses in the three barns and two horses that were euthanized after exhibiting the most serious symptoms of the virus indicate some horses in those barns could have equine herpesvirus. All quarantined horses are prohibited from moving in or out of those barns.The horses aren't allowed to train with the general horse population. A plan for special training hours was in the works the afternoon of May 18.Churchill has reinstated a requirement that all horses entering the grounds have a 24-hour health certificate similar to one required when a strangles quarantine was in place earlier this year at Churchill's Trackside training center in Louisville.Churchill vice president of communications John Asher said the quarantine could last 21 days from the last reported postive up to one month."While test results have not yet confirmed it, clinical signs observed in several horses and post mortem results on two horses indicate that we are dealing with equine herpesvirus," Kentucky state veterinarian Dr. Robert Stout said. "Equine herpes virus is contagious, so our efforts are now focused on containing the virus to the quarantine areas until our concern about further transmission has eased to the point that these horses can rejoin the general horse population." "There is every indication that this outbreak was detected early, and that the recommended containment measures will be effective," Churchill president Steve Sexton said. "We do not anticipate any significant impact on our operations in our spring meet, which continues through July 10."Stout and Sexton were among the more than 100 people that attended a 10:30 a.m. EDT meeting Wednesday at the Churchill recreation center. Horsemen were told to report any horse with a temperature of 101 degrees or higher and were given fact sheets on equineherpes virus and precautionary measures.Sexton told horsemen TCO2, or "milkshake" testing was suspended to keep horses separated. Blood for the tests is drawn from each horse every racing day in a common barn near the quarantined barns. Churchill will, however, conduct post-race milkshake tests.Rusty Ford of the Kentucky State Veterinarian's Office told The Blood-Horse Tuesday night an "indication" of equine herpesvirus was the reason for the quarantine. Definitive results weren't available Wednesday morning.Shipping agent Paul Holthus told The Blood-Horse Wednesday morning none of the Preakness starters was stabled in the barns now under quarantine. They would be permitted to leave Louisville for Pimlico racecourse in Baltimore Wednesday morning, he said.Expected on one of three scheduled flights is Kentucky Derby (gr. I) winner Giacomo. Holthus said horses trained by William Cesare and Steve Asmussen were not permitted to travel because their barns are under quarantine.One Asmussen trainee, Bwana Charlie, remained on the grounds at Churchill. He had been scheduled to race Saturday in the Maryland Breeders' Cup Handicap (gr. III).On Wednesday, three horses from the affected barns were scratched from the Churchill program, officials said.Werner confirmed Wednesday morning that his Churchill barn is under quarantine. He told The Blood-Horse only one of his horses was infected with the virus. "It started up about a week ago," Werner said. "I've got 20 horses in the barn that aren't infected, but they are affected."Werner, who was disinfecting stalls, shanks, and other equipment Wednesday morning, said a 2-year-old filly he trained lost her mobility in her stall the week of May 9 and eventually was euthanized. He said equine protozoal myeloencephalitis (EPM), which affects the nervous system, was suspected as the cause until test results showed it was equineherpes virus.McGee said his barn technically isn't under quarantine, though he was asked "not to send any horses to the track" for training.According to veterinarian Nancy S. Loving, writing in the June 2005 issue of The Horse magazine, equine herpesvirus is classified into five different strains. EHV-1 and EHV-4 are the strains associated with viral respiratory disease. EHV-1 is the most prevalent concern in horse populations not only because its respiratory disease is more virulent than that caused by EHV-4, but also because it can lead to viral abortion in mares or neurologic disease.Fever and an upper respiratory infection are the most common signs of EHV-1. Infected horses may show signs of lethargy, poor appetite, nasal discharge, and a cough. An infected horse can spread the virus up to 35 feet, with a cough or snort. The virus is short-lived and susceptible to disinfectants.Detection of EHV-1 in three horses at Turfway Park in March 2003 just days before that track's major event, the Lane's End Stakes (gr. II), did not disrupt the race, though track officials took several precautionary steps to ensure the health of the horses at the Northern Kentucky track.The Turfway outbreak occurred within one barn, which was put under quarantine for 21 days. Horses shipped in to the track during that period were housed only in the receiving barn or stakes barn, and all stalls in those barns were stripped and thoroughly sanitized.In a separate incident that same month, five horses at Penn National racecourse in Pennsylvania also tested positive for EHV-1. That outbreak led officials at Philadelphia Park and at racetracks in West Virginia to impose a temporary ban on shipping horses to and from Penn National. Two of the five horses died as a result of EHV-1.In January and February of 2003, an outbreak of EHV-1 at the University of Findlay in Ohio led to the death of 12 horses.Live Discussion at NoonDr. Catherine Kohn, a specialist in internal medicine and a professor in the Department of Clinical Sciences at The Ohio State University School of Veterinary Medicine, will answer your questions about equine herpesvirus (EHV-1) during a special edition of bloodhorse.com's "Talkin Horses" today from noon-1 p.m. She joins senior correspondent Steve Haskin, who will answer questions about horses preparing for this Saturday's Preakness Stakes (gr. I).Dr. Kohn is not directly involved with the situation at Churchill Downs that has led to a quarantine of three barns, but she has first-hand experience working during a herpesvirus outbreak in Ohio. Click here to ask Dr. Kohn any questions you have about EHV.
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