9 Causes Of Encephalitis In Children, Signs And Treatment

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Encephalitis is a serious infection and inflammation of the central nervous system that affects the brain parenchyma (tissue). The most prevalent cause of encephalitis in children is viral infections, with symptoms ranging from mild flu-like symptoms to severe neurological impairments.

Although up to 50% of children with encephalitis may develop long-term complications, early diagnosis and treatment can considerably reduce the mortality rates (1).

Encephalitis is not contagious in itself; however, the virus or other infectious agents that cause it can be contagious. Therefore, preventive and precautionary steps can lower your child’s risk of catching infections, especially during outbreaks.

Read this post to learn about the many types of encephalitis and its causes, risk factors, symptoms, complications, prevention, diagnosis, and treatment options in children.

Types Of Encephalitis

Encephalitis can be divided into two categories depending on the cause (2).

  • Primary encephalitis: This occurs when a virus or other causative agents directly infect the brain. This infection can be widespread or localized to one brain area. Primary encephalitis may result from reactivation of a virus that has been inactive after a previous infection.
  • Secondary encephalitis: This is caused when a faulty immune system attacks the healthy brain cells in response to an infection elsewhere in the body. It may occur two or three weeks after an infectious disease and is often called post-infection encephalitis.

Causes Of Encephalitis In Children

The exact cause of encephalitis in children is often not known. However, when the cause is known, it is generally a viral infection. The common viral causes of encephalitis may include (2) (3) (4)

  1. Herpes viruses:  Both herpes simplex virus (HSV) type 1, which causes cold sores, and herpes simplex type 2 associated with genital herpes. HSV type 1 rarely causes encephalitis, but when it does, it can cause significant brain damage and even death.  Other herpes viruses such as the varicella-zoster virus that causes shingles and chickenpox and the Epstein-Barr virus that causes infectious mononucleosis can also result in encephalitis.
  1. Mosquito-borne viruses: West Nile virus, La Crosse encephalitis virus, Western equine encephalitis virus, Louis encephalitis virus, Japanese encephalitis virus, eastern equine encephalitis virus, and Zika virus are some common causes of mosquito-borne encephalitis. The signs and symptoms of the infection may appear after a few days or weeks following exposure to the mosquito-borne virus.
  1. Enteroviruses: The poliovirus and coxsackievirus, which are enteroviruses associated with flu-like symptoms, abdominal pain, and eye inflammation, can also lead to encephalitis in children.
  1. Tick-borne viruses: The Powassan virus is a common cause of tick-borne encephalitis in the Midwestern United States. Bites from infected ticks or consumption of unpasteurized dairy products from infected cows, goats, or sheep can transmit this virus to humans, and the symptoms may appear a week after a bite.
  1. Rabies virus: This can cause rapid progression to encephalitis after the symptoms This virus can be transmitted to humans from an infected animal bite. Cases of encephalitis due to the rabies virus are rare due to effective vaccinations in various countries.
  1. Childhood infections: Measles (rubeola), German measles (rubella), and mumps are some common childhood infections that can result in secondary encephalitis. However, MMR vaccines have reduced the incidence of these diseases in many countries.

Other causes of encephalitis in children may include

  1. Bacterial and parasitic infections: Although viruses are the common causes of encephalitis in children, parasites, fungi, and bacteria can also cause encephalitis in rare cases. Tuberculosis, syphilis, and Lyme disease (tick-borne) are common bacterial infections that may result in encephalitis. Parasitic infections such as toxoplasmosis mediated by cats can also lead to encephalitis in children.
  1. Fungal infections: Fungi including candida and aspergillus can also cause fungal encephalitis in children.
  1. Non-infectious causes: A cancerous or noncancerous growth (tumor) in the body can also cause autoimmune encephalitis.

Encephalitis in itself does not spread from an infected person to others. Instead, the infectious agent is transmitted. Protecting your child from various infectious agents could reduce their risk of contracting encephalitis.

Risk Factors For Encephalitis In Children

Although anyone can develop encephalitis, the following factors may increase the risk for encephalitis in children (2).

  • Weakened immune system: Children who have HIV/AIDS, take immunosuppressant drugs, or are under any medical conditions that can cause a weakened immunity are at an increased risk for encephalitis.
  • Age: Children and older adults are vulnerable to most types of viral encephalitis and often develop severe encephalitis than other age groups
  • Seasons and geographical regions: Incidence of mosquito- and tick-borne encephalitis may change based on seasons and geographical regions. This can be more common in the summer in many areas of the United States. Children who reside or travel to high-risk areas are more likely to develop mosquito-borne or tick-borne encephalitis than other children.

Signs And Symptoms Of Encephalitis

A viral infection can precede encephalitis in most cases. Gastrointestinal problems such as nausea, vomiting, and diarrhea and upper respiratory symptoms are commonly seen prior to the onset of encephalitic symptoms.

The severity and type of symptoms may vary in each child depending on the underlying cause and individual factors. The common signs and symptoms of encephalitis may include (5)

  • Headache
  • Bulging fontanelle in young children
  • Fever
  • Photosensitivity
  • Lethargy
  • Sleepiness
  • Irritability
  • Neck stiffness
  • Skin rashes
  • Seizures
  • Impaired speech
  • Hallucinations
  • Altered alertness
  • Unsteady gait
  • Confusion
  • Lack of appetite
  • Nausea
  • Vomiting

These symptoms can also be seen in other medical conditions, especially neurological problems. Therefore, it is advised to consult a pediatrician for an exact diagnosis if you notice any of the symptoms listed above in your child.

Complications Of Encephalitis In Children

The complications of encephalitis may vary depending on various factors, including age, underlying cause, the severity of the initial illness, and the time between the onset of encephalitis to treatment. Children with mild encephalitis may recover within a few days or weeks without any long-term complications.

Brain tissue injury due to severe inflammation can result in the following complications (2).

  • Lack of muscle coordination
  • Memory problems
  • Paralysis
  • Personality changes
  • Speech difficulties
  • Hearing impairment
  • Vision defects
  • Coma
  • Death

Also, the type and severity of complications may vary in each child depending on the brain area involved. In some children, these problems may persist for months, while in others, the complications may be permanent.

Diagnosis Of Encephalitis

The pediatrician may inquire about your child’s health and vaccination history to know the possible causes of encephalitis. They may also ask about the recent travel history to know if the child has been to any mosquito- or tick-prone areas. The following tests are usually ordered for children with suspected encephalitis (6).

  • Magnetic resonance imaging (MRI) is a non-radioactive technique to visualize the tissues. MRI with special dye (contrast) gives clear images of the brain parenchyma (soft tissues).
  • Computed tomography (CT) scan uses X-rays to create images of the inside of the body. Certain brain changes specific to encephalitis are noted on CT scans.
  • Blood tests and blood culture may help determine the presence of infections and inflammatory markers in the blood. NMDA receptor antibodies and other antibodies can also be identified in blood tests.
  • A sputum culture may help identify respiratory tract infections in children.
  • Stool and urine tests are also useful for determining the underlying causes.
  • Spinal tap or lumbar puncture involves the collection of cerebrospinal fluid (CSF) using a needle. It enables the doctor to measure the CSF pressure in the spinal canal and brain.
  • Electroencephalogram or EEG records brain electrical activity through electrodes placed on the scalp.
  • Brain biopsy is done in rare cases to identify the exact cause. This includes the removal of a small sample of brain tissue.

Doctors may order these tests based on the existing signs and symptoms and other risk factors. Some tests are also ordered during follow-up visits to ensure recovery.

Treatment For Encephalitis

The treatment for Encephalitis may vary depending on the underlying causes. Children with encephalitis often require hospitalized treatment for two weeks or a month, and intensive care unit (ICU) admissions are needed for severe cases.

Supportive care is provided for initial stabilization. Two to three days of intravenous treatment with antiviral medications for herpes simplex encephalitis and antibiotics for bacterial infections are often given while waiting for the laboratory analysis.

Specific medications are given after the cause of encephalitis is confirmed. Immunosuppressants such as high-dose steroids are recommended for children with autoimmune causes. Although most children may receive a single course of immunosuppressants, a few may require them for a longer time. Some children may need plasmapheresis (process to filter blood) and intravenous antibodies to manage encephalitis (7).

If the causes are not identified, doctors may focus on preventing complications through medications or other methods while the child recovers from encephalitis. Children who recover from encephalitis are also provided with specialized training and therapies to improve their neurological functioning.

How To Prevent Encephalitis In Children?

Encephalitis may not be preventable in many cases. However, you can protect your child from various diseases that cause encephalitis. The following are a few preventive measures you can take to protect your child (8).

  • Vaccinations: Providing all childhood vaccines as per the immunization schedule can help prevent various illnesses that cause encephalitis in children.
  • Avoid contact: Avoiding being around a person infected with viruses that cause encephalitis may reduce the risk of transmission.
  • Maintain hygiene: Washing the hands with soap and water or rubbing with alcohol-based sanitizer and following the cough and sneeze etiquettes may reduce the risk of viral and other infectious diseases in children.
  • Avoid mosquito bites: Using mosquito repellents and nets, wearing protective clothing outdoors, and cleaning the waterlogged spots around the house can protect your child from mosquito bites.
  • Avoid tick bites: Using tick repellents and wearing protective clothing can help avoid tick bites in travelers and residents of endemic areas. Avoiding consumption of unpasteurized dairy products is also recommended to prevent tick-borne encephalitis.
  • Rabies vaccine: It is recommended to take rabies vaccines after a bite from stray animals, including bats and unvaccinated domestic animals. Ensure that the pets are up to date with their recommended vaccines.

You may keep your child safe from encephalitis by following these preventive and precautionary measures since these diseases are common in many places.

Frequently Asked Questions

1. Can my child live a normal life after encephalitis?

After undergoing proper treatment, the prognosis of several patients with encephalitis has been found to be good, and they are expected to make a good recovery. But there might still be certain nerves in the brain that might not be fully functional and, in turn, affect the quality of life of your child (3).

2. Can my child get encephalitis twice?

The chances of encephalitis relapsing are rare. However, if the treatment is not working and the symptoms are getting severe, it might give rise to complications such as seizures (9).

3. How long can you have encephalitis without knowing?

The symptoms of encephalitis can be easily confused with those of the flu. Therefore, one might go for about a week or two without the actual diagnosis.

Viral diseases such as herpes, rabies, and enteroviruses are the most common causes of encephalitis in children. The symptoms might range from mild flu-like symptoms to serious neurological problems. Similarly, the prognosis varies depending on the underlying cause and severity, but early detection and treatment can help many children avoid brain damage. If your child exhibits any neurological signs, you must seek medical care from a pediatrician. Regular follow-up and suggested therapy, such as speech and occupational therapies, can also help. Moreover, getting vaccinated and maintaining proper hygiene could help prevent the disease.

Key Pointers

  • Viral infections could cause encephalitis in children.
  • Fever, sensitivity to light, confusion, swollen fontanelle are a few signs of this condition.
  • Severe encephalitis could cause fatigue, muscle loss, and other complications.
  • Timely vaccinations, proper hygiene, and avoiding mosquito breeding sites could help prevent encephalitis.


MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.
1. Dirkje de Blauw et al.; Epidemiology and Etiology of Severe Childhood Encephalitis in The Netherlands
2. Encephalitis; St. Clair Health
3. Encephalitis; National Health Service
4. Meningitis and encephalitis in infants and children; ResearchGate
5. Encephalitis In Children; Children’s Hospital of Philadelphia
6. Encephalitis; St. Louis Children’s Hospital
7. Encephalitis; Boston Children’s Hospital
8. Acute Encephalitis Syndrome and Children: What You Need to Know; Medanta
9. Encephalitis; Cedars Sinai
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Dr Bisny T. Joseph

Dr. Bisny T. Joseph is a Georgian Board-certified physician. She has completed her professional graduate degree as a medical doctor from Tbilisi State Medical University, Georgia. She has 3+ years of experience in various sectors of medical affairs as a physician, medical reviewer, medical writer, health coach, and Q&A expert. Her interest in digital medical education and patient education made... more

Dr. Dur Afshar Agha

Dr. Dur Afshar Agha is a consultant pediatrician with decades of experience in various medical facilities both in Pakistan and Saudi Arabia. She has headed the Department of Preventive Pediatrics at the prestigious, Children’s Hospital and Institute of Child Health in Pakistan and is a life member of the Pakistan Paediatric Association. She has also completed her Post Graduate Program... more