In many horses, the first or only sign of EHV-1 infection is fever, which can go undetected. | Photo: Stephanie L. Church/The Horse

The Idaho State Department of Agriculture (ISDA) has received confirmation of a second case of equine herpesvirus-1 (EHV-1) in that state this year.

A mare at a private equine training facility in Bannock County aborted a pregnancy in late March. On April 4, the ISDA received laboratory confirmation the abortion was caused by EHV-1 infection, despite the mare being current on her vaccinations.

The horse has not traveled to any events or locations since fall 2018 and is currently under veterinary care at the private facility, which is under quarantine. She had been in direct contact with two other horses at her home facility. None of the three horses have exhibited respiratory or neurologic signs of disease, and they do not have regular contact with horses in training at the facility