A property in Sussex County, N.J. has been quarantined after one horse developed highly infectious equine herpes myeloencephalopathy (EHM).
The horse, a 20-year-old mare, developed acute clinical signs Aug. 3, and was euthanized. A week earlier, another horse on the property had similar neurological signs and was euthanized without diagnostic testing. EHM, often deadly, is the neurologic form of Equine Herpes Virus (EHV-1) infection.
The remaining horse on the premises are under quarantine and being monitored. No horses from the property, which is in an undisclosed location, have been moved, making the risk of disease spread very low.
“The department took swift action to prevent the disease from spreading to other horses by enacting a quarantine, which stops movement of horses in and out of the properties and puts in place preventive measures to contain the virus,” said state Secretary of Agriculture Edward Wengryn.
The EHV-1 organism spreads quickly from horse to horse and can cause respiratory problems, especially in young horses and spontaneous abortions in pregnant mares. The neurologic form of the virus can result in death. The incubation period of EHV-1 is typically two to 10 days.
Clinical signs include respiratory disease, fever, nasal discharge, depression, cough, lack of appetite, and/or enlarged lymph nodes. In horses infected with the neurologic strain of EHV-1, clinical signs typically include mild incoordination, hind-end weakness/paralysis, loss of bladder and tail function, and loss of sensation to the skin in the hind end.
The virus spreads readily through direct contact with infected materials. The virus is endemic in the country and although highly infectious, it does not persist in the environment for an extended period and is neutralized by hand soap, alcohol-based hand sanitizers, and sunlight. The virus does not affect humans and other domestic animals, except for other Equidae and Camelids (llamas and alpacas).
The NJDA Animal Health Diagnostic Laboratory is available to assist veterinarians with the EHV-1 testing. For contact information, go to the lab website: www.jerseyvetlab.nj.gov. Owners should consult with their veterinarian prior to taking any action, as the clinical signs of infection with the neurological form of EHV-1 (EHM) are common to many other diseases. EHM is a reportable disease in New Jersey. If an owner has a horse exhibiting neurologic signs or suspects Equine Herpes, they are directed to call their veterinarian immediately.