California animal health officials have confirmed the state’s first equine case of West Nile virus (WNV) for 2016.

“On July 1, 2016, an unvaccinated 5-year-old … Thoroughbred mare in San Diego County (which was) displaying neurologic signs including ataxia, depression, stiffness in neck and spine, and severe lip twitching was confirmed positive for West Nile virus,” the California Department of Food and Agriculture (CDFA) said in a July 6 statement. “The onset of clinical signs began on July 24. The mare is alive and recovering slowly.”

Last year, California confirmed WNV in 19 horses, five of which died or were euthanized, according to the CDFA’s website.

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 (twitching); 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%