Encephalitis Information Week

Day Two: Tuesday, October 18, 2021.

The first annual Encephalitis Information Week (October 18 to 25) is aimed at healthcare professionals and the general public and helping them to discover more about encephalitis, the latest in research, as well as our resources which may be useful for managing encephalitis and recovery and rehabilitation.

If you have any questions, please get in touchBecome a member of the Encephalitis Society. Membership is free.

Today we look at What is encephalitis and its symptoms.

What is encephalitis?

What is encephalitis?

Encephalitis is an inflammation of the brain. It is caused either by an infection invading the brain (infectious encephalitis) or through the immune system attacking the brain in error (post-infectious or autoimmune encephalitis).

Anyone at any age can get encephalitis. There are up to 6,000 cases in the UK each year and potentially hundreds of thousands worldwide. In the USA, there were approximately 250,000 patients admitted to hospital with a diagnosis of encephalitis in the last decade.

How the brain works

  • In order to understand the effects of encephalitis, it can be helpful to understand how the brain works

What are the Symptoms of encephalitis?

Infectious encephalitis

  • Infectious encephalitis usually begins with a ‘flu-like illness’ or headache. Typically more serious symptoms follow hours to days, or sometimes weeks later. The most serious finding is an alteration in the level of consciousness. This can range from mild confusion or drowsiness, to loss of consciousness and coma. Other symptoms include a high temperature, seizures (fits), aversion to bright lights, inability to speak or control movement, sensory changes, neck stiffness or uncharacteristic behaviour.

Autoimmune encephalitis

  • Autoimmune encephalitis often has a longer onset. Symptoms will vary depending on the type of encephalitis related antibody but may include: confusion, altered personality or behaviour, psychosis, movement disorders, seizures, hallucinations, memory loss, or sleep disturbances.


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