Equine Herpesvirus (EHV-1) Outbreak, Information Developed by eXtension, MyHorse University

What is EHV-1?

• Equine herpesvirus is one of the most common respiratory diseases affecting horses. There are at least four equine herpes viruses.
  
• EHV1 and EHV4 are the two herpes viruses that commonly cause respiratory disease.
  
• EVH1 can also cause neurologic disease.
  
• EHV-1 is commonly found in horse populations worldwide and was previously referred to as the equine abortion virus. Although EHV-1 is well known for causing reproductive disease, it is also known to cause respiratory and neurological disease.
  
• Transmission occurs when infected and uninfected horses come in either direct (nose to nose contact) or indirect (through buckets, clothing, blankets that are contaminated) contact with nasal discharges of infected horses. The virus can travel via aerosol (in the air) for short distances.
  
• In horses infected with the neurologic strain of EHV-1, clinical signs may include: nasal discharge, incoordination, hind end weakness, recumbency, lethargy, urine dribbling and diminished tail tone.

Online Resources
•AAEP Resources on EHV : http://www.aaep.org/ehv_resources.htm
Find EHV-1 updates, informational resources and information on individual states on The American Association of Equine Practitioners' (AAEP) EHM & EHV Resources webpage.

•USDA EHV Resources : http://www.aphis.usda.gov/vs/nahss/equine/ehv/
The United States Department of Agriculture's Animal & Plant Health Inspection Service has collected a number of resources on EHV-1 including informational brochures about the disease, as well as outbreak information from previous years.

• Equine Herpesvirus-1 (EHV-1): What Horse Owners Should Know: http://www.thehorse.com/Videos/Webinars.aspx
(Recorded on May 25, 2011) The Horse Webinar.

• Understanding EHV-1: Knowledge is Contagious Webinar http://www.equisearch.com/horses_care/understanding-ehv-1-knowledge-is-contagious-webinar/

(Recorded on May 26, 2011) Equus.

Extension Resources and Publications on EHV-1
•Neurologic Equine Herpes Virus (EHV-1), http://extension.usu.edu/files/publications/publication/AG_Equine_2008-03pr.pdf Utah State
Informational publication written by Dr. Kerry A. Rood, Utah Extension Veterinarian and Dr. L. Earl Rogers, Utah State Veterinarian. Read more about the background, clinical signs, diagnosis and prevention of Neurologic Equine Herpes Virus (EHV-1).

•Equine Herpes Virus, http://equineextension.colostate.edu/content/view/221/57/ Colorado State University
Informational article about EHV, including the mode of transmission, the primary and secondary symptoms, the treatment options, applicable vaccinations and what you can do to prevent your horse from contracting the disease.

•Equine Herpesvirus Fact Sheet, http://animalscience.uconn.edu/extension/publications/herpesvirus.htmUniversity of Connecticut
Informational fact sheet written by Jenifer Nadeau, Associate Professor and Equine Extension Specialist at the University of Connecticut. This fact sheet touches on the different types of equine herpesvirus, clinical signs, routes of transmission and how to protect your horses from EHV.

Biosecurity Information/Resources for Horse Farms

•Protect Your Barn and Horses from Disease: http://myhorseuniversity.com/resources/webcasts/feb2011
Learn about evaluation methods and advice for prevention, protection, and proactive ways of minimizing disease risk in your horse facility by watching this recorded webcast, hosted by Dr. Betsy Greene, Professor of Animal Science and Extension Equine Specialist at the University of Vermont.

•USDA Horse Biosecurity Brochure: http://www.aphis.usda.gov/publications/animal_health/content/printable_version/HorseBioSecurity_final.pdf
The United States Department of Agriculture has provided this brochure with general suggestions and guidelines regarding biosecurity on horse farms, including topics on transporting horses and using disinfectants.

•AAEP Biosecurity Guidelines & Recommendations: http://www.aaep.org/pdfs/control_guidelines/Biosecurity_instructions%201.pdf
The American Association of Equine Practitioners has organized this document with various biosecurity guidelines and recommendations for farms that house horses with EHV-1 or horses that have been exposed to the virus. Read about management of manure and bedding, as well as methods of disinfection horse equipment and facilities.