The Indiana State Board of Animal Health has quarantined a Lake County, Ind., boarding facility after a horse was confirmed positive for equine herpesvirus-1 (EHV). The horse was humanely euthanized after showing neurologic signs before he was confirmed for the virus. The 45 other horses at the stable will remain under quarantine until all are confirmed free of the disease.

Although it’s not transmissible to humans, EHV-1 is highly contagious among horses and camelids, and it is generally passed from horse to horse via aerosol transmission (when affected animals sneeze/cough) and contact with nasal secretions. The disease can cause a variety of ailments in equines, including rhinopneumonitis (a respiratory disease usually found in young horses), abortion in broodmares, and myeloencephalopathy (EHM, the neurologic form).

Myeloencephalopathy is characterized by fever, ataxia (incoordination), weakness or paralysis of the hind limbs, and incontinence. Should a horse with potential EHV-1 exposure display any of the aforementioned clinical signs, a veterinarian should be called to obtain samples and test for the disease.

The virus is most commonly spread through horse-to-horse contact, and aerosolized respiratory particles; horses can appear healthy while spreading the virus through respiratory secretions. Physical objects such as tack, grooming equipment, buckets, and people can also be vectors for passing the virus