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  • Encephalitis is swelling and irritation (inflammation) of the brain most often from an infection.
  • Encephalitis is treated in the hospital. Your child may get IV fluids and medicines to treat infections and prevent seizures.
  • The best way to prevent encephalitis is to prevent infections. Ask your healthcare provider how to take care of your child at home.


What is encephalitis?

Encephalitis is swelling and irritation (inflammation) of the brain. Encephalitis can damage the brain and cause problems with movement, talking, and memory. It is rare but can be life-threatening. Anyone can get encephalitis, but it happens more in babies, elderly people, and people who have a weakened immune system or who have a long-term disease such as diabetes or HIV. The immune system is your body’s defense against infection.

What is the cause?

Encephalitis is usually caused by a virus such as:

  • Herpes simplex virus, which causes sores on the face and genitals
  • Varicella-zoster virus, which causes chickenpox
  • Enterovirus, which causes flu-like symptoms
  • Viruses carried by insects such as the West Nile virus, which is carried by mosquitos
  • Rabies virus, which is carried by animals

Encephalitis can also be caused by:

  • Bacterial infections such as tuberculosis, Lyme disease, and bacterial meningitis
  • Fungal infections such as histoplasmosis and candidiasis
  • Parasitic infections such as toxoplasmosis

Viruses, bacteria, or fungi can get to the brain by moving from another part of the body through the blood. The source may be an infection in the sinuses, ears, mouth, lungs, heart, or other places. Germs in the brain cause the tissue to swell and bleed causing infection and brain damage.

Severe allergic reactions, cancer, or an autoimmune disease can also cause encephalitis. An autoimmune disease is a disease that causes your body to mistakenly attack your own tissue.

What are the symptoms?

Your child’s symptoms may depend on what part of the brain is affected. At first, your child may have flu-like symptoms such as headache, fever, and muscle aches. Over several hours or days, the symptoms may get worse. More severe symptoms may include:

  • Unusual drowsiness
  • Confusion or changes in alertness
  • Changes in behavior or irritability
  • Sensitivity to light
  • Pain or stiffness in the neck
  • Trouble talking or understanding speech
  • Skin rash
  • Bulging at the soft spot on an infant’s head
  • Lack of appetite or poor feeding in a baby
  • Vomiting
  • Fever
  • Seizures
  • Coma

If your child is confused, unresponsive, or has seizures, call 911 for emergency help right away.

How is it diagnosed?

Your healthcare provider will ask about your child’s symptoms and medical history and examine your child. Tests may include:

  • Blood tests
  • CT scan, which uses X-rays and a computer to show detailed pictures of the brain
  • MRI, which uses a strong magnetic field and radio waves to show detailed pictures of the brain
  • EEG (electroencephalogram), which uses small wires pasted or taped to your child’s head to measure and record the electrical activity of his or her brain
  • Lumbar puncture, also called a spinal tap, which uses a needle to get a sample of fluid from the area around your child’s spinal cord

How is it treated?

Encephalitis is treated in the hospital. Your child may be in the intensive care unit. If your child needs help breathing, your child may need a breathing machine. These life-support treatments are used until your child starts to get better. Your child may need IV fluids and medicines to:

  • Treat a viral, bacterial, or fungal infection
  • Prevent or treat seizures
  • Prevent or treat brain swelling
  • Prevent or treat nausea and vomiting

Your child may start a rehabilitation (rehab) program to help with problems caused by the illness. This may include physical therapy, occupational therapy, or speech therapy.

  • Physical therapy can help your child’s muscles get strong again.
  • Occupational therapy may help if your child has problems doing things like eating and getting dressed.
  • Speech therapy may help if your child has problems with swallowing, speaking, or understanding words.

How can I take care of my child?

Follow the treatment plan your child’s healthcare provider recommends.

Ask your provider:

  • How and when you will get your child’s test results
  • How to take care of your child at home
  • How long it will take your child to recover from this illness
  • If there are activities your child should avoid and when your child can return to normal activities
  • What symptoms or problems you should watch for and what to do if your child has them

Make sure you know when your child should come back for a checkup. Keep all appointments for provider visits or tests.

How can I help prevent encephalitis?

The best way to prevent encephalitis is to prevent infections. You can do these things to help prevent infections:

  • Get all recommended vaccines.
  • Avoid contact with others who are sick.
  • Wash your hands often and especially after using the restroom, coughing, sneezing, or blowing your nose. Also wash your hands before eating or touching your eyes.
  • Don’t share food or eating and drinking utensils with others.
  • Keep surfaces clean especially bedside tables, surfaces in the bathroom, and toys for children. Some viruses and bacteria can live several hours or more on surfaces such as cafeteria tables, door handles, and desks. Wipe them down with a household disinfectant according to directions on the label.
  • Take precautions to avoid insect bites:
    • Stay indoors at dawn, dusk, and in the early evening when mosquitoes are most likely to be around.
    • Wear long pants and long-sleeved shirts, especially from dusk to dawn. This is the time when you are most likely to get bitten.
    • Use an insect repellent whenever you are outdoors.
    • Some insect repellents can make children ill if they put it in their mouth or swallow it. Never let young children play with or put insect repellent on themselves. Adults should put repellent on their own hands, and then put the repellent on the child’s body. Children older than 2 months can use repellents with no more than 30% DEET.
    • After coming in from outdoors, undress and check your child’s body for ticks. Tics usually crawl around for several hours before biting. Check your child’s clothes, too. Wash them right away to remove any ticks. If you find a tick attached to your child’s body, remove it.
Developed by Change Healthcare.
Pediatric Advisor 2022.1 published by Change Healthcare.
Last modified: 2020-02-24
Last reviewed: 2019-09-04
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
© 2022 Change Healthcare LLC and/or one of its subsidiaries
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