At Least One New Case of EHV-1 in Pennsylvania Department officials state they are working to notify those that participated in the scavenger hunt in early May. 

At Least One New Case of EHV-1 in Pennsylvania

Pennsylvania officials announced Monday a Forest County stable is under quarantine after a horse tested positive for the equine herpes virus (EHV-1).
A preliminary epidemiological investigation is underway after test results came back positive on May 13th. A horse from the Forest County barn participated in the Tionesta Wounded Warrior Horseback Scavenger Hunt on May 2nd in Tionesta. More than 90 horses and their riders from other states, including Ohio and West Virginia, competed in the event.
Department officials state they are currently tracing the horses that participated in the scavenger hunt. Health officials in Ohio and West Virginia have been notified.
Two more horses from the Forest County stable are showing signs of illness after being exposed to the EHV-1 positive horse.
Another stable in Clarion County is under precautionary quarantine after an exposed horse showed clinical signs of EHV-1. Lab results are pending. The quarantines will remain in effect for 21 days from the last date of any new cases at each facility. During the time, strict bio-security is enforced.

EHV-1 may lie dormant for long periods of time and then re-activate during a period of stress, which can result in clinical disease.

Symptoms may include fever, decreased coordination, nasal discharge, urine dribbling, loss of tail tone, hind limb weakness, lethargy, and the inability to rise. While there is no cure, the symptoms of the disease may be treatable.
This is the second confirmed case of EHV-1 in Pennsylvania since the end of March.