Encephalitis (Inflammation Of The Brain)

Jun 27, 2022

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Encephalitis, also known as brain inflammation, is a disease caused when viruses or bacteria damage brain tissue. It occurs for many reasons.

What is Encephalitis?

Encephalitis can be briefly described as inflammation of the brain tissue. In the later stages of encephalitis, which causes symptoms such as fever, behavioral disorders and headache, some neurological symptoms are also observed. It is not known exactly how encephalitis, which can be fatal if not treated early, affects patients.

Encephalitis, which can occur in people of all ages and genders, is more common in infants, people with AIDS and HIV, and cancer patients. Encephalitis is also more common during periods of epidemics.

Causes of Encephalitis

The exact factors that cause encephalitis to develop are not known, but it is generally thought to be of viral origin. On the other hand, bacterial infections and some non-infectious inflammatory conditions can cause brain inflammation. Brain inflammations are generally divided into 2 groups.

Primary Encephalitis

In primary encephalitis, bacteria or viruses directly reach the brain tissue and cause infection there. In this type, the infection can be concentrated in a specific area or spread over a very wide area. In viral infections, reactivation of a previous viral disease can also cause inflammation.

Secondary Encephalitis

In secondary encephalitis, the inflammation occurs in any part of the body. The immune system responding to this infection attacks not only the pathogens causing the infection but also the brain tissues, causing inflammation in the brain. Secondary encephalitis usually occurs 2 or 3 weeks after the illness.

Viruses Most Commonly Causing Encephalitis

EEncephalitis is usually of viral origin. The most common viruses that cause this condition are the following.

Herpes Simplex Virus/span>

The herpes simplex virus is usually responsible for cold sores in the mouth. It is also one of the most common causes of secondary encephalitis. This virus, which can cause death in advanced stages, is seen in one in 500 thousand people in the world every year. It also causes permanent damage to the body.


The symptoms of the disease caused by these viruses are often the same as those of the flu. It can also manifest itself as eye inflammation and abdominal pain. This family of viruses also includes polio and coxaca viruses. It is therefore possible for encephalitis caused by enteroviruses to cause symptoms similar to polio.

Mosquito-borne Viruses

Mosquitoes feed on human blood. Therefore, when they suck the blood of an infected person, they can easily transmit the infection to other people. Infections caused by mosquitoes appear a few days after the bite.

Tick-borne Viruses

Tick-borne viruses are caused by the transmission of viruses carried by ticks to humans. In tick-borne encephalitis, patients usually have symptoms such as headache, joint pain and high fever. As the disease progresses, it is possible to experience more serious symptoms.

Rabies Virus

The rabies virus, which is usually transmitted by the bite of an infected animal, causes inflammation in the brain. However, it rarely gives this result compared to other viruses.

Childhood Infections

The most common cause of secondary encephalitis is childhood illnesses such as mumps, measles or rubella. The only way to prevent these diseases is to carry out their stages regularly.

Encephalitis Risk Factors

Encephalitis can occur in people of all ages and genders, but is more common in certain risk groups.


Encephalitis usually occurs in infants, children and the elderly.

Weak Immune System

People with weak immune systems are more vulnerable to viruses and bacteria. This increases the risk of developing encephalitis.


The features of brain inflammations caused by mosquitoes or ticks are more common in spring and summer seasons.

Geographical Region

Because mosquitoes and ticks are more common in some geographical areas, encephalitis is also more common in these areas.

How is Encephalitis Diagnosed?

Diagnosis of encephalitis requires a detailed physical examination along with the patient’s medical history. Afterwards, some tests are applied to the patients to confirm the diagnosis.

Imaging tests

MRI and CT provides a detailed visualization of any swelling or tumor in the brain.

Lumbar Puncture

With this test, changes in the spinal fluid help to identify infections in the brain. This test can also detect whether brain infections are caused by bacteria or viruses.

Laboratory Tests

These tests, which examine blood, urine and biopsy samples, also look for the presence of any infection in the body.


With this test to measure the electrical activity of the brain, abnormal brain waves help diagnose encephalitis.


Brain biopsy, which is an extremely dangerous procedure, is not performed unless it is very necessary. Examination of a tissue sample taken from the brain provides a clear diagnosis of the disease.

Symptoms of Encephalitis

Patients with viral encephalitis usually have no symptoms. In case of symptoms, the symptoms are flu-like. Symptoms seen in these patients are as follows:

  • Fatigue,
  • Powerlessness,
  • Muscle and joint pains,
  • Fire,
  • Headache,

Patients with advanced encephalitis have more severe symptoms. These symptoms include the following:

  • Loss of consciousness
  • Speech disorders,
  • Behavioral disorders,
  • Muscle weakness,
  • Paralysis in some parts of the body,
  • Seizures,
  • Hallucinations,
  • Confusion

The symptoms caused by encephalitis in infants and children are as follows.

  • Stiffness in some parts of the body,
  • Causeless anger,
  • Malnutrition
  • Nausea,
  • Vomiting,
  • Swelling in the fontanelle,

Finally, there are symptoms of encephalitis that require urgent medical attention. These symptoms include the following:

  • Loss of consciousness,
  • High fever,
  • Loss of sensation in some parts of the body,
  • Muscle weakening,
  • Speech disorders,
  • Behavioral disorders,,
  • Double vision
  • Blurred vision
  • Seizures,
  • Bad odor perception,,
  • Headache that does not go away and is severe,

Encephalitis Treatment

The treatment of encephalitis depends on the factors that cause the disease. Once encephalitis has been diagnosed, the underlying cause needs to be investigated and identified..

Antiviral treatments

Since the most common cause of encephalitis is viral infections, patients are usually treated with antiviral therapy. In addition, taking measures to protect people from viruses prevents the development of the disease..

Patients are recommended bed rest and plenty of fluid intake during the treatment process. In addition, antiviral drugs with active ingredients such as acyclovir, ganciclovir and foscarnet are used as antivirals. However, antiviral drugs are not effective in viral diseases caused by insect bites. For this reason, patients are given treatments to support their immune systems.

Supportive Care

In the treatment of patients with severe encephalitis, supportive care methods should also be applied to patients.

  • Use of medication to stop or reduce the frequency of seizures,
  • Administration of corticosteroids to relieve swelling and pressure inside the brain,
  • Fluid therapy to maintain essential mineral levels,
  • Inhaler for respiratory support,
  • Regular monitoring of heart function,
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