The document provides an update on an outbreak of Equine Herpes Virus-1 (EHV-1) across several states. It summarizes that as of the date, there were 4 quarantined facilities in Utah with 7 confirmed and 8 suspect EHV-1 cases, and 2 horses euthanized. A total of 51 horses across 9 states had confirmed EHV-1 infections, with 8 horses euthanized. EHV-1 can cause respiratory disease, abortion, or potentially fatal neurological disease. The document reviews the clinical signs, diagnosis, treatment, vaccination protocols, and control measures to limit further spread during an outbreak.