On Feb. 19, the Texas Animal Health Commission (TAHC) confirmed Equine Herpes Virus (EHV-1) in two horses in El Paso County.
Both horses showed signs of respiratory illness, fever and nasal discharge when evaluated by a local veterinarian. The horses tested positive for EHV-1 but neither horse showed signs of the neurologic form of the disease. The stable has been placed under movement restriction as a precaution, and all horses are being monitored daily.
To date, 74 horses linked to Sunland Park in New Mexico have been confirmed EHV-1 positive. Only two of the 74 horses are stabled near El Paso, Texas.
Direct horse-to-horse contact is a common route of transmission of the virus. Indirect transmission is also possible and occurs when infectious materials (nasal secretions, fluids from abortions, etc.) are carried between infected and non-infected horses by people or inanimate objects such as buckets, tack, trailers etc.
Symptoms of EHV-1 include fever, which is one of the most common clinical signs and often precedes the development of other signs. Respiratory signs include coughing and nasal discharge. Neurologic signs associated with EHV-1 are highly variable, but often the hindquarters are most severely affected. Horses with EHV-1 may appear weak and uncoordinated. Urine dribbling and loss of tail tone may also be seen. Severely affected horses may become unable to rise.
It is important to remember that none of these signs are specific to EHV-1, and diagnostic testing is required to confirm EHV-1 infection. Many horses exposed to EHV-1 never develop clinical signs. If you suspect your horse has been exposed to EHV-1, contact your veterinarian.
In general, exposed horses should be isolated and have their temperatures monitored twice daily for at least 14 days after last known exposure. If an exposed horse develops a fever or other signs consistent with EHV-1, diagnostic testing may be performed. Owners should work with their veterinary practitioner to establish appropriate monitoring and diagnostic plans for any potentially exposed horses.