Encephalitis is an acute inflammation of the brain. Usually the cause is a viral infection, but bacteria can also cause it. It can be mild or severe. Most cases are mild. Examples of viral infections that can cause encephalitis include herpes simplex virus (the virus that causes cold sores and genital herpes), varicella zoster virus (the chickenpox virus), mumps virus, measles virus and flu viruses. In the UK, the most common virus to cause encephalitis is herpes simplex virus.

Most cases of encephalitis are caused by the virus directly infecting the brain. However, sometimes encephalitis can develop if your immune system tries to fight off a virus and, at the same time, attacks the nerves in your brain in error. This is known as post-infectious or autoimmune encephalitis. Rarely, this type of encephalitis can develop after an immunisation.

Adult patients with encephalitis present with acute onset of fever, headache, confusion, and sometimes seizures. Younger children or infants may present irritability, poor appetite and fever. Neurological examinations usually reveal a drowsy or confused patient. Stiff neck, due to the irritation of the meninges covering the brain, indicates that the patient has either meningitis or meningoencephalitis.

Vaccination is available against tick-borne and Japanese encephalitis and should be considered for at-risk individuals.

Post-infectious encephalomyelitis complicating small pox vaccination is totally avoidable now as small pox is now eradicated. Contraindication to Pertussis immunisation should be observed in patients with encephalitis. An immunodeficient patient who has had contact with chicken pox virus should be given prophylaxis with hyperimmune zoster immunoglobulin.

9 Nursing Diagnosis for Encephalitis
  1. Hyperthermia
  2. Acute Pain
  3. Impaired physical mobility
  4. Impaired gas exchange
  5. Disturbed thought processes
  6. Risk for impaired skin integrity
  7. Risk for deficient fluid volume
  8. Imbalanced nutrition: Less than body requirements
  9. Anxiety