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Alerts and Important Animal Health Information

Health Alert: Equine Herpes Virus

Equine Herpes Virus (EHV-1) impacts horses and can cause respiratory disease, abortion in mares, neonatal foal death, and/or neurologic disease. The virus can spread through the air, contaminated equipment, clothing and hands.   According to the University of Kentucky Equine Research Center, the virus’s ability to reside as a silent and persistent infection in horses provides for continual transmission. It is vital that good biosecurity measures be implemented on exposed premises.

Horse owners need to be mindful that most horses are exposed to one or more strains of EHV at a very young age.  Periods of high stress or additional exposure may cause an animal to exhibit clinical signs of disease.  Occasionally, the disease is exhibited as a serious neurologic disease.  Owners should consult with their veterinarian when deciding whether or not to attend an equine event as anytime horses are commingled there is the opportunity for exposure.

The United States Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) states, the incubation period of EHV-1 is 1-10 days; typically signs are seen within 1-3 days post exposure. 
Viral shedding occurs for 7-10 days, but can occur up to 28 days from the onset of signs. 

The neurologic signs include ataxia, urinary bladder atony and reduced tail tone. In severe cases, horses will be unable to stand; these cases have a very poor prognosis. Foals are rarely affected with the neurologic form of EHV-1, and no sex predilection is seen. Treatment is supportive and tailored to the specific case. 

Once a horse is infected, it should be quarantined.  USDA recommends isolating and monitoring of all exposed horses for at least 7 days. During the isolation period, it is recommended to discontinue or reduce any strenuous training or exercise for exposed horses. 

All exposed horses should have rectal temperatures taken twice daily (8-12 hours apart) and recorded in a log for at least 7 days after the date of potential exposure. Horses whose rectal temperature registers higher than 101.5 degrees Fahrenheit are considered to be febrile. All horses on the premises should also be monitored for neurologic signs (ataxia, posterior incoordination, weakness, recumbency with inability to rise, circling, head pressing, head tilt, bladder atony) during the home quarantine period. Central nervous system signs, such as posterior incoordination, weakness, recumbency with inability to rise, and bladder atony are most common in EHM affected horses. 

More info:

Avian Influenza Information and Biosecurity Measures:


CWD Rules Revised


USDA Announces Federal Order for Reporting PEDV



PEDV Reporting and Herd Management Plan Information and Requirements





PEDV General Information

The National Pork Board has provided valuable information regarding Porcine Epidemic Diarrhea Virus (PEDV) at the link below.

Stakeholders are encouraged to visit this link for information on biosecurity, research, and disease updates.



The American Association of Swine Veterinarians has provided timely information on PEDV disease updates, research, laboratory submission guidelines, fact sheets, and additional resources. These resources can be accessed at the the link below.



AASV PEDV Information