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Disease Alerts

Updates on current disease outbreaks are listed here as they occur and will include the date listed, disease name, location and current status. Specific premises will not be named but the general location by town, county and state will be listed. When locations, events or horses are at risk they will be listed. Updates will be posted as they are received.



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Clackamas County, OR
Outbreak Identifier: 5229
Alert ID: 2605
June 02, 2022
Confirmed Case(s) - Official Quarantine

Oregon Department of Agriculture

Number Confirmed: 1;

Facility: Ranch
Clinical Signs: Neurologic signs; Horse Status: Euthanized;
Notes: A horse from Clackamas County recently tested positive for Equine Herpesvirus (EHV-1). After exhibiting neurologic symptoms, the owners called a private veterinarian to examine the animal and collect a sample for testing. Unfortunately, the horse was later humanely euthanized—a California laboratory-confirmed EHV-1 on May 31. The horse owner reports the animal recently traveled to the 2022 State Oregon High School Equestrian (OHSET) Teams Championship. OHSET was held at the First Interstate Bank Expo Center in Redmond, Oregon, from May 12-15. A second horse from the same ranch who also traveled to OHSET is doing well, recovering from initial respiratory symptoms. However, an ODA District Veterinarian placed a quarantine on the farm following state and national guidelines. The ODA State Veterinarian is working with OHSET to evaluate the potential exposure risk at the state event, and event coordinators are working to contact exhibitors. All horse owners who believe that their horse may have been exposed to EHV-1 should monitor their animal’s temperature twice daily and call their veterinarian if they see any symptoms. For more information go to EHM factsheet.