Officials at the Bureau of Animal Health and Welfare in Illinois enforced a quarantine at Double W Stables in Gurnee, Ill., on March 6. Two horses at the facility were euthanized after developing clinical neurological symptoms of Equine Herpes Virus-1. Double W Stables is a boarding facility located in Lake County, about an hour from Chicago.

In addition, at least eight horses on the premises were also showing clinical symptoms of EHV-1, but had not yet been diagnosed. It is not believed that the horses had contact with any horses from the Florida EHV-1 outbreak. “At the present time, no link has been established between these affected horses and any organized equine event,” said a press release from the Illinois Department of Agriculture.