A multi-state outbreak of equine herpesvirus myeloencephalopathy (EHM), a highly contagious and sometimes fatal neurological disease, has prompted heightened caution among horse owners in Pennsylvania. The state Department of Agriculture confirmed three new cases in Lancaster, Clinton, and York counties, with quarantines imposed on affected farms. Prairie Fire Farms Foundation in Lebanon County has canceled public events and restricted horse adoptions to prevent exposure, emphasizing strict biosecurity measures such as limiting horse transport and using separate equipment. Symptoms of EHM include fever, nasal discharge, incoordination, and hind limb weakness, and while humans cannot contract the virus, they can carry it on clothing.

The outbreak traces back to rodeo events in Oklahoma and Texas in November, affecting horses from 31 states and Canada, though recent Pennsylvania cases are unrelated to that source. The Department of Agriculture is collaborating with veterinarians nationwide to track and contain the virus, urging horse owners to monitor symptoms closely and report suspected cases. Despite the seriousness of EHM, most cases are non-fatal with proper veterinary care and quarantine. Horse owners are advised to follow updated guidelines from the Equine Disease Communications Center to protect their animals.