The Kentucky State Veterinarian’s office announced Aug. 27 that a Fayette County horse has tested positive for West Nile virus (WNV), the second confirmed case in the commonwealth this year.

In a statement Kentucky Equine Programs manager E.S. "Rusty" Ford relayed that the 7-year-old Thoroughbred-cross mare with no history of vaccination first showed signs of illness on Aug. 24. During the following 48 hours, the mare demonstrated “increasing evidence of weakness,” and on Aug. 26 developed muscle fasciculations (twitching) and hind-limb ataxia (incoordination). As of Aug. 27, the attending veterinarian reported that the mare is responding favorably to treatment.

In 2014 Kentucky confirmed four cases of WNV in horses on four premises.

West Nile is transmitted to horses via bites from infected mosquitoes. Clinical signs for WNV include flulike signs, where the horse seems mildly anorexic and depressed; fine and coarse muscle and skin fasciculations; hyperesthesia (hypersensitivity to touch and sound); changes in mentation (mentality), when horses look like they are daydreaming or "just not with it"; occasional somnolence (drowsiness); propulsive walking (driving or pushing forward, often without control); and "spinal" signs, including asymmetrical weakness. Some horses show asymmetrical or symmetrical ataxia. Equine mortality rate can be as high as 30-40%