What is encephalitis?

Encephalitis, or inflammation of the brain, is a rare disease that's usually caused by a virus such as influenza (flu), herpes simplex type 1 or 2, rabies, chicken pox, or West Nile Virus. Viruses can be transmitted from person to person such as by coughing and sneezing, or by touching an object that's been touched by an infected person. We can also get viruses by way of a tick or mosquito bite. Because the root cause of encephalitis is usually a virus, the condition is commonly referred to as viral encephalitis.

There is no way to prevent encephalitis since there's no way to prevent viruses. It helps to be aware, however, that young children, the elderly, and people with weakened immune systems (such as people living with HIV) may be more susceptible to getting encephalitis.

Symptoms of encephalitis

Mild cases of encephalitis may go unrecognized because symptoms, if you have any at all, are similar to other conditions. You might experience:

  • Fever
  • Headache
  • Lack of appetite
  • Low energy

In rare cases, symptoms of encephalitis may include:

  • Changes in personality
  • Confusion, disorientation
  • Difficulty speaking
  • Seizures

If you have symptoms that worry you or you know you have been exposed to a virus, don't ignore your symptoms. Get in touch with a doctor who can diagnose your condition.


If diagnosed and treated promptly, the prognosis is positive for most people with encephalitis. Your doctor may order a blood test to determine what bacteria or virus is causing your symptoms. You may also have a CT scan or MRI to check for swelling or bleeding in the brain. Depending on what is causing encephalitis and how severe the inflammation is, treatment may include anti-viral medication, steroidal injections and other therapies.

If you or a loved one is diagnosed with encephalitis, your condition will need to be closely monitored by a medical professional as complications from encephalitis can quickly occur and every patient's response to the disease is different.


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