The Michigan Department of Agriculture and Rural Development (MDARD) reported Aug. 29 that it has received confirmation of the state’s first case of Eastern equine encephalitis (EEE) in a horse for 2017.

“The one-year-old Standardbred colt from Wexford County developed a fever and was unable to rise,” the MDARD said in a statement on its Facebook page. “The colt was not vaccinated against EEE and did die.”

In 2016 Michigan had two confirmed equine EEE cases—one in Clare County and one in Menominee County—according to USDA Animal and Plant Health Inspection Service statistics.

A viral disease, EEE affects the central nervous system and is transmitted to horses by infected mosquitoes. Clinical signs of EEE include moderate to high fever, depression, lack of appetite, cranial nerve deficits (facial paralysis, tongue weakness, difficulty swallowing), behavioral changes (aggression, self-mutilation, or drowsiness), gait abnormalities, or severe central nervous system signs, such as head-pressing, circling, blindness, and seizures. The course of EEE can be swift, with death occurring two to three days after onset of clinical signs despite intensive care. Horses that survive might have long-lasting impairments and neurologic problems