There are several viruses in the EHV family. The more common and serious are EHV-1 and EHV-4. EHV-1 has four manifestations the neurological form, respiratory disease, abortion and neonatal death. EHV-4 causes a nonfatal upper respiratory tract disease in foals and is uncommonly associated with abortion and rarely with neurological disease.
After infection the incubation period can vary, typically 4 to 10 days. Signs to look for with the respiratory form nasal and ocular discharge, but not a lot of coughing. There may also be some enlargement of the submandibular lymphnodes, under the jawbone. With the neurologic form a fever, temperature over 102 degrees F, may be the only warning sign. Followed quickly in a 24-48 hour period of other signs including:
Strange gait
Lethargy
Hind limb weakness
Head tilt
Inability to rise, leaning for balance
Seizures
A veterinarian can take a nasal swab to make a proper diagnosis.
EHV is highly contagious and spreads from horse to horse contact through respiratory secretions as well as direct contact. It is also spread via horse to human to horse as well as horse to object to horse. Humans cannot catch the equine herpes virus. That is why is imperative to have proper isolation and quarantine procedures. And to follow a strict disinfection procedure of all items including tack and trailers. Scrub then sanitize. Humans need to change their clothes.
There is no cure for the herpes viruses. Once a horse has recovered, not all do, the virus is dormant in their system. It can re-emerge at any time, particularly when the horse is stressed.
Recently a farm in southern Erie County was reported to have EHV-1. I thought it would be beneficial to share information on the topic. As a professional pet sitter I want my clients to know that I have not visited this location. Also I take the best precautions possible between visits and appreciate being informed of any situations you are aware of.
References where you can read more details:
Good Communication: http://www.equinediseasecc.org/outbreaks.aspx