Hawthorne: Additional horses test positive for herpesvirus

STICKNEY, Ill. – An outbreak of equine herpesvirus at Hawthorne Race Course has taken a turn for the worse, with horses in two barns other than the one housing the first herpesvirus cases either testing positive for the EHV-1 virus or showing symptoms of the disease.

The Illinois Department of Agriculture decided Friday not to put Hawthorne under a formal quarantine, but horses here cannot leave the grounds except for a medical emergency, and horses shipping in must remain at Hawthorne until the track is virus-free.

The situation has started to strain Hawthorne’s ability to race: Eight races were carded for Sunday and Wednesday compared to the usual nine, and the race week could be shortened from five days to four days in two weeks, assistant general manager Jim Miller said.

Two horses in barn K-1 returned positive tests for EHV-1 after running fevers but showing none of the virus’s more serious symptoms of the virus. Those horses are trained by Roger Brueggemann, who also has horses in Barn A, the barn that has been isolated since the initial cases of herpesvirus were discovered Oct. 14. Those horses have been isolated with other horses that have returned positive tests but haven’t shown the life-threatening neurological symptoms the virus can cause.

A horse in Barn C, however, has become the sixth horse afflicted with EHV-1’s neurological component. Test results hadn’t come back, but the horse is presumed to have EHV-1, and also has been isolated.

“This is likely not confined to one barn,” said Dr. Dawn Folker-Calderon, the state-employed veterinarian at Hawthorne. “We were trying to isolate one barn, but now we’re treating the whole track as one barn.”

A van carrying horses from Fairmount Park was turned away at the Hawthorne stable gate Thursday night, but that was during a period when Folker-Calderon and Dr. Mark Ernst, the Department of Agriculture state veterinarian, still were determining how the situation would be handled. Horses coming from Fairmount Park and Hoosier Park in Indiana will be allowed onto the Hawthorne backstretch with proper health certification. Hoosier’s meet ends Saturday and several trainers plan to ship stock to Hawthorne for the winter.

Even if the number of cases remains limited, the virus could impact much of a meet that ends Dec. 30. All horses that have been sick or tested positive for EHV-1 must test negative, followed by a 21-day period to ensure no new cases arise, before normal operations resume. Moreover, if the outbreak continues widening, the Department of Agriculture could institute a formal quarantine and begin administering to the backstretch itself, which could mean a cessation of racing.