Advertisement - Scroll to continue

What is Encephalitis?

Encephalitis is a m­edical term doctors use­ to describe inflammation of the brain tissue. In this­ condition, the inflammation is so severe that it causes the brain to swell.

There are­ several potential causes of Encephalitis: bacterial and viral infections, autoimmune rea­ctions, bites of insects such as mosquitoes, fleas, and ticks, and sometimes cancer. However, regardless of contributing factors, Encephalitis is a major threat to human health.

Encephalitis is not a widespread disease, and it is normal not to know anyone­ who suffers from it. Still, it is a life-threatening­ problem resulting in unwelcome and severe health issues like neck stiffness, seizures, high body temperature that exceeds ­100 degrees Fahrenheit, and­ more.

How Common is Encephalitis?

According to the estimations, Encephalitis is not a worry affecting many people. Due to the number of people it involves, it can be considered a minor issue in society. But as far as a single affected individual is concerned – it is a perilous scenario for them. But let's focus on the pure data: doctors know that approximately every ten to fifteen people per 100,000 is struck with Encephalitis. Although it is not of great value, Encephalitis has stability, striking several people each year. 

How Dangerous is Encephalitis?

It is very unlikely that you will have Encephalitis. But when you do, what does it mean for your health? How much does it impact a person's existence? The unfortunate answer is that it can change one's life significantly. It can affect the mind, causing personality changes and weakening the body, causing fatigue, sickness-like symptoms, and more severe issues like seizures. Therefore, it is a hazardous condition that can lead to long-term problems with health and even death.

Fortunately, if you receive treatment, your outlook improves. Benign cases of Encephalitis tend to go away entirely. But to increase the chances of recovery, regardless of the severity of Encephalitis, you need to cooperate with a healthcare professional or, in some situations, more than one.


Specialists differentiate between four variations of Encephalitis: Arbovirus encephalitis, Viral Encephalitis, autoimmune Encephalitis, and Bacterial or fungal Encephalitis.

Arbovirus encephalitis is when a person gets encephalitis from infections spread by mosquitoes, ticks, or fleas.

Viral Encephalitis is the type that occurs more often than other variations. It happens due to viral infections and diseases.

Encephalitis may sometimes occur as an anomaly within a patient's body. This internal issue happens when the immune system attacks the brain, changing how it works and causing inflammation. It is then referred to as autoimmune encephalitis (or paraneoplastic syndrome) and is more often observed in cancer patients.

Finally, Bacterial or fungal Encephalitis, as the name suggests, develops because of the harmful effects of fungi and bacteria. This type is very rare compared to the other two.


The National Institute of Neurological Disorders and Stroke estimates that causes of encephalitis are not identified in 60% of patientsTrusted Source. Despite that, many causes are possible, such as diseases, viruses, fungi, and bacteria; connecting a specific microorganism or virus to a singular case is challenging.

That being said, some factors are observed more often to cause encephalitis. For example, they include viruses that spread thanks to insects. Examples of the most common ones include:

Viruses that spread by other means include:

Encephalitis: What Is, Causes, Symptoms, Treatment, and Protection

Risk Factors

No one is entirely safe from being affected by Encephalitis, but some people are more at risk. This is because several factors come into play, contributing to the development of inflammation of the brain tissue.

A factor that is linked to many conditions, including Encephalitis, is age. Depending on which age group you belong to, you are more susceptible to different medical conditions. In the case of brain inflammation, however, older adults and children are more at risk of viral Encephalitis. However, when autoimmune Encephalitis is concerned, young adults and children get it more often.

Secondly, the time of the year and geographical location are essential factors. Diseases spread by mosquitoes, fleas, and ticks are more common in certain regions, especially during summertime in most American states.

Another risk factor is smoking. It is harmful to your health in some ways, but what only a few people know is that it can result in paraneoplastic autoimmune Encephalitis — a complication of Lung Cancer.

Autoimmune Encephalitis is also more likely to affect you if you already have an autoimmune condition. As a reminder, an autoimmune disease is when the immune system mistakenly attacks its cells.

Finally, having a compromised or weakened immune system increases the chance of Encephalitis. Particularly, conditions like HIV/AIDS and drugs with immune-suppressing properties may lead to brain inflammation.

Signs and Symptoms

Many different and unwelcome problems are associated with encephalitis. This is because early warnings differ from symptoms of late, severe stages. Autoimmune encephalitisTrusted Source and other types do not necessarily cause the same problems. First, let's take a closer look at the most common symptoms shared between most patients:

If the condition progresses to a subsequent stage, it can make you experience the following symptoms:

Before we discuss other aspects of Encephalitis, it is also vital to mention the course of this condition in infants. Here are the symptoms that you may notice if your child is affected:

Encephalitis: What Is, Causes, Symptoms, Treatment, and Protection


Many specialists argue that benign cases of Encephalitis rarely result in permanent, long-term, or severe health difficulties. But it can't be said about the later stages of encephalitis, which are characterized by severe problems. 

The nature of these complications is usually neurological, stemming from brain damage gradually inflicted by inflammation. One such undesirable possibility is problems with hearing and speaking- you may find yourself challenged by simple tasks such as saying something or listening to others speaking. On top of that, your personality may undergo a peculiar change, and your memory gets worse than before. 

If personality changes occur, this may manifest as unexplainable and unwanted episodes of anger and frustration. Also, a patient's mod may jump from happiness to sadness suddenly.

Other undesired Outcomes are persistent fatigue, drowsiness, vision problems, and Epilepsy.

Diagnosis and Tests

Healthcare specialists assess Encephalitis based on physical exams, interviews with patients, and reviewing symptoms. Me­dical history, especially the presence of autoimmune diseases, is useful in determining the possibility of brain inflammation. If there is a reason to suspect this problem, doctors may recommend tests such as lumbar puncture, imaging, ­and more. 

Spinal Tap

A spinal tap, or lumbar puncture, is a procedure your healthcare provider may recommend to diagnose Encephalitis. It involves procuring a sample of cerebrospinal fluid from the lower back. If the sample consists of high protein levels or a high white blood cell count, it may indicate brain inflammation.

Imaging Exams

Imaging tests like MRI and CT are valuable tools to diagnose neurological conditions. Magnetic resonance imaging (MRI) is used to detect brain swelling but also rule out other health issues, including tumors and strokes. On the other hand, computed tomography (CT) is helpful to determine if there are changes in the brain structure.


A sample procured from the brain (Biopsy) may be needed in rare scenarios. It is usually performed if encephalitis progresses and does not respond to known forms of treatment. The sample is sent to a lab for further investigation.

Blood Tests

Blood tests include a comprehensive metabolic panel (CMP) and complete blood count (CBC). They may detect the presence of some viruses.


There are many ways to address brain inflammation, which depends on the type of inflammation and its severity. These options include:

Antiviral drugs – Like the name suggests, these types of medication treat cases of viral brain inflammation.

Steroids – Steroids are prescribed when the patients suffer from viral or autoimmune Encephalitis and experience brain pressure and swelling of the brain. Steroids known as Corticosteroids help reduce this issue. 

Antiseizure drugs – These medications may benefit the patient if autoimmune brain inflammation causes seizures.

Breathing support – Supplemental oxygen and mechanical ventilationTrusted Source assist patients with severe Encephalitis who have difficulty breathing.

Improving mental health – Cooperation with a psychologist may be crucial if a patient experiences problems with memory or their personality undergoes sudden, unexplainable changes.

Antifungal drugs – If fungi lead to Encephalitis, antifungal medications treat it.

Immune globulin – This is a type of drug that treats cases of autoimmune brain inflammation.

Prognosis for Encephalitis Patients

Most profess­ionals agree that the prognosis for patients with mild brain inflammation is generally favorable. Complications are uncommon in these instances. 

However, 100% recovery does not occur in all cases. Brain inflammation results in long-term issues in ab­out 10 – 20% of patients. The most often observed include seizures, problems focusing, behavioral swings, and changes in speech.

In these instances, additional therapies are advised. These encompass coping methods that help deal with undesired issues due to encephalitis. Depending on the type of brain inflammation and severity of symptoms, the following therapies may be helpful:

Psychotherapy­ – It helps develop coping mechanisms and methods to deal with symptoms. It works best for beha­vioral disruptions like personality changes and sudden mood swings.­

Occupational­ Therapy – Helps perform everyday tasks, increasing the overall quality of life.­

Physical­ Therapy – If a doctor believ­es that a patient's flexibility and strength need to be improved, they may advise attending physical therapy sessions. They help increase the patient's coordination skills, such as balance and muscle strength.­

Speech­ Therapy – If Encephalitis causes spe­ech problems, speech therapy may be beneficial. It allows the patient to relearn how to use muscles to speak adequately.­

When You Should See A Doctor?

Seeing a healthcare provider is advised when experiencing Encephalitis symptoms. If you receive treatment early, the risk of unwanted long-term complications decreases significantly, improving the general outlook. The symptoms you should look out for the most are neurological issues (behavioral changes, problems speaking, hearing, and eyesight defects).


Vaccines­ play a crucial role in preventing encephalitis as they offer defense against the viruses that can cause­ this condition, which is when the brain swells due to viral infection.

Vaccines aid the immune system in generating a response to produce unique antibodies against the virus contained in the vaccine. When an individual who has been vaccinated encounters this virus again, their body recognizes and quickl­y neutralizes it, preventing illness or at least reducing its severity.

The MMR vaccineTrusted Source for Measles, Mumps, and Rubella, helps defend against the ­viruses that cause these illnesses. It reduces the risk of severe complications such as Encephalitis. Similarly, the chickenpox vaccine protects against issues caused by the varicella-zoster virus, which may also result in in­ encephalitis.

Vaccines assist in protecting individuals and contribute to community immunity. When a large number of persons within an area are resistant to a virus, it can prevent the spread of that virus within the group. This type of safeguarding is beneficial as it encompasses individuals unable to receive vaccinations owing to medical conditions or adverse responses they possess towards constit­uents within the vaccine.

Protection from Bites

Inflammation­ of the brain caused by infections can be avoided. They are often caused by insects carrying the virus, so you­ can prevent the infection with proper protection and countermeasures.

The first­ and most important line of defense against insect bites is what you wear. Your protective garderobe should include a hat­ covering your ears and a long-sleeved shirt. It is cru­cial to protect as much skin as possible.

Insects like­ mosquitoes lay their eggs in damp environments, including homes and apartments. For reproduction, they may use flower pots, garbage cans, and other places that contain­ water. Keep your prop­erty dry and clean to reduce the risk of mosquitoes in your home.

Finally, insect repe­llents and window screens can help keep these unwelcome guests at bay. While window screens make it harder for insects to invade your home, insect repellents with DEET protect when they are­ inside.


February 28, 2024
10 minutes read

Table of Contents

Find a topic by its first letter
Epstein Barr Virus: What Is, Symptoms, Diseases, and Treatment
Epstein Barr Virus

Epstein Barr Virus is a pathogen that causes infectious mononucleosis and many other diseases. Learn about the risks associated with… read more »

Ebola: What Is, Types, Spreading, Symptoms, and Signs

The Ebola virus continues to pose a threat to those living in Africa. Learn about the risks associated with Ebola… read more »

Encephalopathy: What Is, Types, Diagnosis, and Treatment

Encephalopathy, in medical lingo, is a frequently encountere­d brain phenomenon. It occurs when the brain's functioning is not optimal. read more »

Herpes: What Is, Types, Symptoms, and Treatment

Herpes is a viral infectious disease that most often affects the lip area. Herpes virus infections are common. What does… read more »

Autoimmune Disease: What Is, Types, Causes, Symptoms, and Treatment
Autoimmune Disease

Autoimmune diseases are conditions in which the immune system works incorrectly – it begins to attack the body's tissues. What… read more »

Genital Herpes: Symptoms, Helpful Prevention, and Treatment
Genital Herpes

Genital herpes is a disease caused by the HSV herpes virus. What symptoms does it give? Check what treatment and… read more »

Adenovirus: What Is, Causes, Signs and More

Adenovirus is a pathogen commonly found in the environment. Find out how to recognise adenoviral infections. Learn about treatment and… read more »

Rabies: What Is, Causes, Symptoms, Diagnosis, and Prevention

Rabies is a viral disease that, in humans, is usually fatal. Vaccinations can successfully prevent it. What are its symptoms?… read more »

AIDS: What Is, Transmission, Symptoms, Diagnosis, Treatment, and Prevention

AIDS is a disease caused by HIV. This virus attacks the cells of the human's immune system, making them unable… read more »