What Is Encephalitis and What Causes It?

What is encephalitis and what causes it?

Encephalitis is inflammation of the brain.

According to whether a virus or other agent directly infects the brain or not, encephalitis can be divided into two types, primary encephalitis and secondary encephalitis.

The most common cause of encephalitis is a viral infection. The following viruses may cause encephalitis:

  • Herpes simplex virus (HSV)
  • Enteroviruses
  • Mosquito-borne viruses
  • Tick-borne viruses
  • Rabies virus

Bacterial infections and noninfectious inflammatory conditions also can cause encephalitis, but that is rare.


* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.