SALT LAKE CITY (CBS / AP) – Agriculture officials have warned that horses in Canada and at least five Western states have contracted a fatal equine virus after attending a national competition in Utah.

On Wednesday, Utah state veterinarian Bruce L. King told the Salt Lake Tribune that at least eight horses in Idaho, Utah, Colorado, California and Canada have been infected with a serious, neurological strain of Equine Herpes Virus-1. The Oregon Department of Agriculture said Thursday it had confirmed equine herpes virus in two horses that had attended the show.

The virus is easily spread because it can be airborne and transmitted by touch or through sharing brushes, bits or other equipment, but it doesn’t pose a risk to humans. Symptoms include fever, decreased coordination, nasal discharge, urine dribbling, tail limpness, hind-limb weakness, poor balance and lethargy.

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