Inflammation, or swelling, of the brain is called encephalitis. Most cases of encephalitis follow an infection by a virus. Encephalitis is often a mild illness, but serious cases can cause brain damage.

Symptoms

Encephalitis has a wide range of symptoms. In mild cases patients have a fever and a headache. They may feel tired and not want to eat. In more severe cases patients get a high fever and a severe headache. Even dim light hurts their eyes. They have pain and stiffness in the neck. They cannot hold down food or liquids. In the most severe cases patients become confused. They may drift into a coma, or a deep, heavy sleep. Recovery in those cases can take two weeks or more. There may be permanent damage to the brain and nervous system.

Causes

Viruses, bacteria, parasites, and harmful chemicals can cause encephalitis. Viruses are the most common cause. The viruses that cause chicken pox, mumps, and measles can develop into encephalitis. These viruses spread from person to person. Other viruses that can cause encephalitis, including West Nile virus, are spread by mosquitoes or other biting insects.

Prevention

Washing hands often limits the spread of viruses and bacteria. To avoid insect bites, people should use insect repellent and wear clothing that covers the arms and legs. Vaccines help to stop diseases that can lead to encephalitis.

Treatment

Treatment for encephalitis depends on its cause. To find the cause, doctors may do a test called a spinal tap. They remove some of the fluid that surrounds the spinal cord and check it for viruses and bacteria. If bacteria are present, they prescribe antibiotics. If viruses are present, different medicines may be used. In severe cases doctors may use drugs called steroids to reduce the swelling in the brain. In all cases of encephalitis the patient must rest in bed, either at home or in a hospital.