Encephalitis in Children

Encephalitis in Children

Encephalitis in Children

Encephalitis means inflammation of the brain. The condition is usually caused by viruses. Encephalitis is a rare disease that affects approximately 0.5 per 100,000 individuals. Children, the elderly, and those with an impaired immune system are commonly affected by the disease.

According to the Centers for Disease Control and Prevention, several thousand cases of encephalitis are reported every year. Since the symptoms can be very broad, many encephalitis cases go unreported.

Usually, encephalitis results from a viral infection or when the body's own immune system mistakenly attacks brain tissues. Encephalitis is an acute inflammation that abruptly and rapidly develops. Thus, urgent medical care is required.

Viral infections are the most common causes of this disease. Encephalitis may occur around 1 in 1,000 cases of measles. The infection usually begins with fever and headache. The symptoms may rapidly progress, which include confusion, loss of consciousness, drowsiness, seizure, and even coma.

A number of factors usually determine whether encephalitis can cause mortality. Factors include age and the severity of the disease. Without much ongoing health issues, younger patients usually recover. However, there are increased chances of mortality and complications in older patients.

Two Main Types of Encephalitis

  • Primary Encephalitis - This type of encephalitis happens when a harmful agent directly infects the brain or spinal cord.
  • Secondary Encephalitis - The infection starts elsewhere in the body and then spreads to the brain.

Inflammation of the brain in children may cause the brain to swell. Certain changes in the nervous system may occur such as changes in alertness, seizures, and confusion. Meningitis may also occur at the same time. In meningitis, the membrane that surrounds the brain and spinal cord get inflamed. Both are life-threatening conditions that need urgent treatment.

Signs and Symptoms

Typically, most patients with encephalitis experience headache, fever, and photophobia. Patients may also experience seizures and weakness.

In milder cases of encephalitis, the symptoms may include:

  • Headache
  • Fever
  • Loss of energy
  • Poor appetite
  • General feeling of sickness

Patients who have a more severe case of encephalitis are more likely to experience high fever and symptoms related to the central nervous system, which may include:

  • Nausea
  • Vomiting
  • Severe headache
  • Disorientation
  • Stiff neck
  • Confusion
  • Convulsions
  • Changes in personality
  • Hallucinations
  • Memory loss
  • Speech and hearing problems
  • Drowsiness
  • Coma

Some of these symptoms in infants are difficult to detect. However, the most important signs are:

  • A full or bulging soft spot
  • Vomiting
  • Stiff body
  • Continuous crying (may become worse when the infant is handled or picked up)

Since encephalitis may be accompanied or followed by viral infections, some of the signs and symptoms may occur beforehand. However, encephalitis often occurs without any warning. 

The symptoms may also vary in children. The symptoms are also similar to the symptoms of other health conditions. Thus, if your child is experiencing any symptoms of encephalitis, then make sure that your child is immediately seen by a doctor. 


Since many types of germs can cause encephalitis, there are also several ways for the infection to spread.

  • Herpes Simplex Virus - It is the most dangerous and the most common cause of encephalitis. Cold sores around the mouth are caused by the same virus, but it can be fatal when it attacks the brain. However, it rarely happens.
  • Lyme Disease - Encephalitis can also become a rare complication of Lyme disease, which is spread by rabid animals with rabies or transmitted by ticks.
  • Mosquito-Borne Disease - Several types of encephalitis can be caused by mosquitoes that can transmit viruses. They include St. Louis encephalitis, West Nile encephalitis, and Western equine encephalitis. There has been an increasing concern about the spread of the West Nile virus in the United States over the last several years.
  • Common Childhood Illnesses - They include chicken pox, measles, mononucleosis, and rubella. These illnesses can be followed or accompanied by milder forms of encephalitis. These viral infections are usually spread through inhalation of infected air droplets. 
  • Bacterial Infection - Encephalitis is less commonly caused by bacterial infections such bacterial meningitis. Certain parasitic infections such as toxoplasmosis can also cause encephalitis, especially in immunocompromised individuals. Encephalitis may also occur following bacterial infections such as syphilis and tuberculosis
  • Viral Infection - Vaccination is given to children against viruses such as rubella, measles, chicken pox, and mumps. For this reason, the rate of encephalitis cases due to these diseases has been decreased. Other viral infections, which include upper respiratory infection or illnesses that cause nausea, vomiting, and diarrhea may also cause encephalitis.
  • Autoimmune Reaction - An autoimmune reaction happens when brain tissues are attacked by the body's own immune system. For example, encephalitis may be caused by an antibody that is made against the protein NMDA receptor. These antibodies may be triggered by a tumor.

Risk Factors

The following groups are at an increased risk of encephalitis:

  • Children who are 12 months and below
  • The elderly
  • Immunocompromised individuals

People who reside in areas where ticks or mosquitoes are common have an increased risk of getting encephalitis. These insects are able to carry viruses that can cause encephalitis and they are most active in summer or fall. 


Brain inflammation is not contagious, but the viruses that can cause encephalitis can be contagious. Getting infected by a virus does not mean that the person will develop encephalitis. However, it is better to avoid direct contact with anyone who has encephalitis.


Illnesses that can cause encephalitis can be prevented, although encephalitis itself cannot be prevented. Many common childhood illnesses that follow encephalitis can be prevented by immunization. Thus, it is recommended to follow the correct immunization schedule set by your child's doctor. Avoid direct contact with anyone who has encephalitis. Other preventive measures include:

  • Staying indoors at dawn or sundown when mosquitoes are most active
  • Using insect repellents
  • Wearing of long sleeves and long pants
  • Draining stagnant water in bird baths, buckets, tire swings, and flowerpots to get rid of mosquito breeding grounds. 

Tick bites can be avoided by:

  • Limited contact with vegetation, soil, and leaves
  • When outdoor, children should wear light-colored clothes that have long sleeves and long pants
  • Regularly checking your child and pets for ticks


Most forms of acute encephalitis usually last up to a week. It can take several weeks or months or even longer for a full recovery.


The doctor will ask questions about your child’s vaccination history, medical history, and symptoms. Inform the doctor if your child had a recent cold, digestive disorder, or respiratory illness. Also, inform the doctor if your child had a recent tick bite, has recently traveled, or has been around pets or animals.

Several tests are used by doctors to diagnose the condition:

1. Imaging Tests

These tests are done to check for brain swelling, bleeding, or any other abnormalities. They include: 

  • MRI - Strong radio waves and magnetic fields are used to form images of the anatomical and physiological processes of the body. 
  • CT Scan - This type of imaging scan is used to create images of the inside of the body. It uses a series of X-ray images taken from many angles. Compared to a regular X-ray, more details are shown in a CT scan.

2. Blood Tests

Blood tests are usually done to check the presence of viruses or bacteria and whether the person is producing antibodies against certain harmful pathogens. 

3. Urine and Stool Test

These tests are done to check for other types of infections and other health problems.

4. Sputum Culture

A sputum culture is used to determine the type of harmful microorganism that infects the lungs.

5. Electroencephalogram (EEG)

This test is done to check for abnormal brain waves. It records the electrical signals in the brain through sticky pads that are attached to the scalp.

6. Lumbar Puncture

This procedure is done to check for signs of infection in the cerebrospinal fluid. It can be used to check whether the child has any infection or other nervous system problem. 

7. Brain Biopsy

A child with encephalitis might need a brain biopsy, but in very rare cases. This procedure is done to identify brain abnormalities. It involves the removal of a brain tissue sample. However, a brain biopsy is often recommended in patients who are suspected of having herpes simplex encephalitis (HSE). 


Immediate medical treatment is needed when it comes to encephalitis. Children with encephalitis can be closely monitored in the hospital.

The child's symptoms, general health, the severity of the condition, and age will determine the treatment plan. The main goal of the treatment is to reduce brain swelling and to prevent further complications. To stop the infection and to control fever or seizures, the child will need to take medications. In severe cases, children may require a breathing machine.

Mild cases of encephalitis can be monitored at home. However, most encephalitis cases need hospitalization, usually in an intensive care unit (ICU), where the patient's blood pressure, breathing, and heart rate are closely monitored. Also, to prevent further brain swelling, other body fluids are also monitored.

Most forms of encephalitis are not treated using antibiotics since they are not effective against viruses. However, antivirals can be used for the treatment of some of its types, especially the ones caused by the herpes simplex virus.

Other treatments for encephalitis include:

  • Corticosteroids - They are used in some cases to reduce brain swelling.
  • Anticonvulsants - When the child has seizures, anti-epileptic or anticonvulsant drugs are used. 
  • Fever Reducers or Pain Relievers - To treat fever and headache, over-the-counter medications such as acetaminophen can be used.


A full recovery is achieved by many people. In some cases, permanent brain damage may occur because of brain swelling, which can also cause complications such as speech problems, learning disabilities, lack of muscle control, and memory loss. These complications are lasting. In such cases, occupational therapy, speech therapy, and physical therapy are needed.


The outcome is difficult to predict at the start of illness. However, more serious complications may be caused by some types of encephalitis such as Japanese encephalitis.

Encephalitis can lead to death if brain damage is severe. However, this may rarely happen. People at highest risk of death from encephalitis are those who are above the age of 55 and infants less than one year old.

You will be told by the healthcare team on how to take care of your child at home. After hospital discharge, your child may still need to go for follow-up checkups. Discuss with the healthcare provider about the risks, benefits, and side effects of all treatments.

There are possible complications in the majority of cases. A full recovery is possible in children, but some may have ongoing nervous system problems that affect their thinking, learning, movement, or speech. For this reason, regular check-ups may be needed. Also, for a complete recovery, the child may need to have occupational therapy, speech therapy, or physical therapy.

When to Call the Doctor

Encephalitis needs to be looked at and treated right away. It is a serious and life-threatening condition. Call your healthcare provider right away if your child shows any signs and symptoms of encephalitis.

Immediately consult a doctor if your child has a childhood illness and has a high fever. Seek immediate medical attention if your child has any of the following signs and symptoms:

  • Stiff neck
  • Convulsions
  • Double vision
  • Severe headache
  • Not able to look at bright lights
  • Problems with hearing and speech
  • Difficulty walking
  • Loss of sensation anywhere in the body
  • Difficulty in moving one's legs or arms
  • Memory problems
  • Lethargy
  • Sudden changes in personality
  • Loss of consciousness

Seek immediate medical care if your baby has any of the following signs and symptoms:

  • Any stiffness
  • Lethargy
  • Vomiting
  • Continuous crying
  • Decreased muscle tone or floppiness
  • Poor appetite
  • High fever (more than 100.4 degrees Fahrenheit in babies younger than 3 months old)
  • Bulging or fullness of the baby's fontanel (soft spot)

Some children who show serious symptoms may respond very well to medications while some with mild cases of encephalitis may develop long-term learning issues and epilepsy. The long-term effects of encephalitis, unfortunately, cannot be predicted.