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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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Sheridan County, WY
Alert ID: 864
March 15, 2018

Wyoming Livestock Board

Wyoming Livestock Board confirmed a horse in Sheridan County has tested positive for Equine Herpesvirus Myeloencephalopathy (EHM). The horse has been quarantined at its premise in Sheridan County with 12 other horses. The affected horse began showing neurologic signs on Sunday, March 11 while competing at a barrel racing event at the Cam-plex facility in Gillette. Owners of any horses attending that event should consult with their veterinarians and take precautions regarding exposure risk. At a minimum, these precautions should include close monitoring of the horses and checking their temperatures at least twice daily. If any of the horses show neurologic signs or fever, the owner needs to contact his/her veterinarian and the Wyoming Livestock Board. Although the source of the infection in the quarantined horse is unknown, this horse did compete at the Central Wyoming Fairgrounds in Casper on Thursday, March 1, and at Laramie County Community College, Friday, March 2 – Sunday, March 4. Horses at the events may have been exposed. Because the incubation period for the disease is less than 14 days, clinical signs should have been apparent in any exposed horses. However potentially exposed horses should be monitored for at least 14 days since any possible exposure at events. More information on Equine Herpes Virus can be obtained by contacting the Wyoming Livestock Board Field Office at 307-857-4140 or by going to: https://aaep.org/sites/default/files/Documents/DiseaseFactsheetEHV.pdf and https://aaep.org/sites/default/files/Documents/DiseaseFactsheetEHM.pdf.