On February 25, a Quarter Horse broodmare in Stutsman County, North Dakota, was found to have equine herpesvirus (EHV) after aborting her foal on February 17. A total of forty horses on the farm have been exposed to the virus.
EDCC Health Watch is a marketing program by Equine Network that utilizes data from the Equine Disease Communication Center (EDCC) to generate and distribute verified equine disease reports. The EDCC is an independent nonprofit organization that relies on industry donations to offer open access to infectious disease information.
EHV 101
Herpesvirus is highly contagious among horses and can lead to various health issues such as rhinopneumonitis, abortion in broodmares, and Equine Herpesvirus Myeloencephalopathy (EHM).
EHV-1 infection in horses often presents with fever as the primary or only symptom, which can sometimes go unnoticed. Other common signs in young horses include cough, decreased appetite, depression, and nasal discharge. Pregnant mares typically do not show signs of infection before aborting, which usually happens late in gestation but can occur earlier as well. Abortions may occur anywhere from two weeks to several months after EHV-1 infection.
Horses with EHM usually exhibit fever initially, followed by respiratory infection symptoms. Neurologic signs like incoordination, limb weakness or paralysis, urine retention, loss of tail tone, and recumbency develop a few days later.
Herpesvirus spreads easily through close contact with infected horses, sharing contaminated equipment, or contact with individuals who have been in contact with an infected horse. Implementing routine biosecurity measures, including hygiene and disinfection practices, is crucial to prevent disease spread.
While current EHV-1 vaccines may reduce viral shedding, they do not protect against the neurologic form of the disease. Practicing consistent biosecurity measures is the most effective way to minimize viral transmission, with disease prevention being the key to disease control.