Encephalomyelitis Equine: Clinical Signs, Treatment & Vaccination

sick horse

Encephalomyelitis equine, also known as sleeping sickness, is a serious and potentially fatal disease of horses caused by infection with the equine encephalomyelitis virus. The disease affects all breeds and ages of horses, although some are more susceptible than others. It can be spread through direct contact or through insect vectors such as mosquitoes, ticks, or other blood-sucking insects.

Clinical Signs

The symptoms of encephalomyelitis equine can vary depending on the individual horse and the strain of the virus present. However, some common signs include fever, depression, incoordination, circling behavior, head pressing against walls or objects, muscle tremors, and seizures. In severe cases, paralysis of the limbs or death may occur.


The treatment of equine encephalomyelitis is usually supportive, based on the animal’s clinical signs. Depending on the severity of the case, antibiotics may also be prescribed to help reduce the risk of secondary bacterial infection. 

In cases where the disease has progressed to neurological signs, supportive care such as anti-inflammatory medications, sedatives, and fluids may be necessary. Additional treatments including vitamin E supplements or hyperbaric oxygen therapy may also be recommended by a veterinarian. It is important to note that horses with severe neurological problems associated with EEE may not recover, and euthanasia may have to be considered.


Encephalomyelitis Equine is a virus that affects horses and can be fatal in some cases. Vaccination is the most effective method for the prevention of the disease, administer a primary series of two doses with at least 3 weeks and up to 6 weeks between each dose and should be done annually. There are two kinds of vaccines available: bivalent and multivalent vaccines.  Bivalent vaccines protect against Eastern and Western Encephalomyelitis while multivalent vaccines protect against Eastern, Western, and Venezuelan Encephalomyelitis.


Which form of equine encephalomyelitis occurs most frequently?

Eastern equine encephalomyelitis is the form of equine encephalomyelitis that occurs most frequently. It is caused by a virus and affects horses, mules, donkeys, and other equines.

Is equine encephalomyelitis contagious?

Equine encephalomyelitis EEE is an infection caused by a virus and spread by mosquitos. It is not directly contagious between horses, meaning that it cannot be spread through contact with other infected animals. 

What type of disease is encephalomyelitis?

Encephalomyelitis (EVM) is a contagious and often fatal equine disease caused by several distinct viruses within the family of Bornaviridae. The most common forms of EVM are Eastern, Western and Venezuelan.

Is encephalomyelitis a virus?

Yes, encephalomyelitis is a virus. It belongs to the family Bornaviridae and there are several distinct viruses within this family that cause EVM.


Eastern Equine Encephalitis (EEE)

Equine viral encephalomyelitis: how to spot and report the disease

What's your reaction?

In Love
Not Sure

You may also like

Leave a reply

Your email address will not be published. Required fields are marked *

More in:Health