Encephalitis in adults is a condition affecting the brain and requires prompt treatment to lower the risk of lasting complications or death. It affects 10–15 people per 100,000 each year, with more than 250,000 patients diagnosed in the last decade alone in the U.S. Encephalitis can affect anyone, but more often occurs in younger people.
Primary encephalitis occurs when a virus or other agent directly infects the brain. The infection may be concentrated in one area or widespread. It may also be a reactivation of a virus that had been inactive after a previous illness.
Secondary encephalitis is a result of a faulty immune system reaction to an infection elsewhere in the body. The immune system also mistakenly attacks healthy cells in the brain. Also known as post-infection encephalitis, secondary encephalitis often occurs two to three weeks after the initial infection.
The 7 Causes of Encephalitis
There is no specific cause of encephalitis but the typical trigger is a common viral infection, bacterial infections, and noninfectious inflammatory conditions. The common viral causes of Encephalitis are:
- Herpes simplex virus. It is associated with fever blisters and cold sores. Encephalitis caused by HSV type 1 is rare but can result in significant brain damage or death.
- Other herpes viruses. These viruses commonly cause infectious mononucleosis, and the varicella-zoster virus, which commonly causes chickenpox and shingles.
- Enteroviruses. These viruses include the poliovirus and the coxsackievirus, which usually cause an illness with flu-like symptoms, eye inflammation, and abdominal pain.
- Mosquito-borne viruses. Symptoms of an infection might appear within a few days to a couple of weeks after exposure to a mosquito-borne virus.
- Tick-borne viruses. The Powassan virus is carried by ticks and causes encephalitis in the Midwestern United States.
- Rabies virus. Infection with the rabies virus, which is usually transmitted by a bite from an infected animal, causes a rapid progression to encephalitis once symptoms begin.
- Common childhood infections. Measles, mumps, and German measles are typical causes of secondary encephalitis.
What are the Symptoms of Encephalitis in Adults?
Encephalitis in Adults caused by certain infections or autoimmune processes can show up with characteristic symptoms.
- A sensation of Deja Vu is typical in the early stages of simplex virus encephalitis.
- Flu-like symptoms
- Behavioral changes
- Unusual movement patterns affecting the mouth and face
- Cognitive decline and impaired function of the autonomic nervous system.
- Seizures or abnormal movement of the face or arm
- Aches in muscles or joints
- Fatigue or weakness
How to Prevent Encephalitis?
- Maintain proper hygiene. Wash hands frequently and thoroughly with soap and water.
- Avoid sharing utensils such as spoons and other tableware.
- Maintain good habits and ensure to keep your environment clean.
- Participate in vaccination programs to avoid getting the infection.
- Before traveling, talk to your doctor about recommended vaccinations for different destinations.