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What is encephalitis?

Encephalitis is an inflammation of the brain. There are many types of encephalitis, but it is usually caused by a viral infection.

Mosquitoes and ticks can carry infections that lead to encephalitis. Very rarely, it may happen after a person has another viral illness, such as chickenpox, or as a result of a vaccination against measles. You can't catch viral encephalitis from another person, though some forms of bacterial encephalitis are contagious.

Symptoms of encephalitis include a headache, fever, and mental changes such as confusion, clumsiness and sleepiness.

Some cases of encephalitis are mild and the person recovers completely. Other cases are severe and cause permanent disability or even death.

If you have symptoms of encephalitis, see your doctor immediately. Encephalitis can be quite serious, and may need to be treated in a hospital.

A doctor may prescribe medicines to fight the virus or bacteria causing the infection, anticonvulsants to prevent or treat convulsions, or corticosteroids to reduce brain swelling and inflammation. Medicines may also be used to relieve symptoms.

Reviewed 11/16/2023

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