The Utah state veterinarian’s office has now confirmed nine equine herpesvirus-1 (EHV-1) cases, according to a March 11 statement.

"The state veterinarian’s office is restricting the movement of the infected animals as a precaution to prevent the spread of the disease," the statement read. "The outbreak remains confined to Cache County, as there have been no other reports of EHV-1 symptoms in horses in other areas of the state. Nonetheless, horse owners throughout Utah are advised to take extra biosecurity precautions when taking their animals to shows or public arenas."

The outbreak began Feb. 26 when two horses tested positive for the disease; two additional horses were confirmed to be EHV-1 positive the following day. On March 4, officials announced that two more horses had tested positive for the disease, and by March 6, the case count had risen to seven.

Four of the affected horses have been euthanized as a result of the disease, the March 11 statement read