Equine Herpes Virus - 1 (EHV-1) - DNA virus that causes abortion, respiratory disease and neurologic disease. Fever (>101.5 F) typically precedes other clinical signs. Respiratory signs include nasal discharge and coughing. Abortions are usually late term (>8 months) and occur without warning. Neurologic symptoms include in-coordination, urine dribbling and inability to get up. Fever and respiratory signs may precede neurologic signs.
Transmission - Usually by aerosolization of respiratory secretions. However, virus can stay viable in the environment for several weeks.
Diagnosis - Polymerase Chain Reaction (PCR) testing of nasal swabs and blood, done by your veterinarian.
Treatment - No specific treatment is available. Experimental treatments for the neurologic form include; antivirals, anticoagulants (aspirin) and primarily supportive care.
Prevention - Biosecurity guidelines should be in place for any large group of horses that travel in and out of the facility. Any new horse should be isolated for 28 days. All horses should have their temperature taken at least once daily. Vaccination might be helpful, but has not been proven to be effective against the neurologic form of EHV-1.
The vaccination for Equine Herpes takes about 2 weeks to take effect after it is given, so there is no need to vaccinate your horse at this point. Also, there is no evidence that the vaccine will prevent your horse from contracting the neurological form of herpes, since the horses that died last year at the racetrack in the east were vaccinated.