Sleeping Sickness in horse(equine encephalomyelitis)

Sleeping Sickness (equine encephalomyelitis)
It’s a viral disease that causes inflammation of the brain and spinal cord. Wild birds are a natural reservoir for virus, and mosquitoes that feed on these birds can transmit the virus to mammals, including horses and humans.
Equine encephalomyelitis is the veterinary term for sleeping sickness, a rare viral disease that affects the central nervous systems of the equine species, including zebras, donkeys, and horses.
•Depression (lethargy, drowsy-appearance)
•Refusal of food or drink 
•Unusual aggression
•Sensitivity to light and sound
•Central nervous system (CNS) symptoms such as lack of coordination, head pressing, circling and convulsions
•Spontaneous death, coma, or death occurring some time after infection
The virus is spread when a mosquito bites an infected bird or rodent, and proceeds to bite and feed on the equine
The virus can cause serious illness and often sudden death without prior symptoms
Sleeping sickness is diagnostically challenging because symptoms will vary among horses, and may mirror other diseases of the CNS.  
A full diagnostic evaluation of your horse will be performed, including an evaluation of whether he is experiencing physical, neurological, or behavioral changes. 
The examination must take into account other cases of equine encephalomyelitis in the surrounding areas, as well as fluctuations in mosquito activity at present and within the previous year. Definitive diagnosis may require blood testing. Since death may precipitate symptoms and exam, the diagnosis may be performed postmortem.
There is no specific treatment that will successfully fight equine encephalomyelitis. 
Treatment is primarily supportive and may comprise of a combination of IV fluids in case of food and water reluctance, corticosteroids to reduce inflammation, anticonvulsants, and other medications. 
If your horse recovers, he will likely develop lifelong immunity. Veterinarians should be consulted about the need for revaccination in fully-recovered horses.
Your horse will remain on the veterinary supervised program. Ongoing management will call for provisions of veterinary-specified daily care.
Horse owners must get annual vaccinations for their animals, implement environmental safeguards to minimize proliferation of mosquitos in pastures and barn areas, and avail all horses of proper insect repellant products, such as a mask and ear and body spray.
Recovered horses likely develop lifelong immunity.