Encephalitis

Encephalitis is inflammation of the brain. It may cause headache and stiff neck among other symptoms.

Encephalitis is most often caused by a virus, such as herpes simplex viruses, which cause cold sores or the varicella zoster virus, which causes chickenpox and shingles. These are called infectious encephalitis.

It can also be caused by:

• Rabies
• Measles
• Mumps
• West Nile virus
• Zika virus
• HIV
• Other viruses

The virus may be spread to a person by other people, animals, ticks, or insects. Mosquito bites are a common way to get a virus that causes encephalitis. Very rarely, encephalitis may be caused by bacteria, fungus or parasites.

Autoimmune encephalitis is another type of encephalitis. It is one of the most common causes of non-infectious encephalitis. With autoimmune encephalitis, the body's immune system makes abnormal disease-fighting substances (antibodies) that attack the brain. Why this happens is not clear. Sometimes tumors or infections can cause autoimmune encephalitis.

Symptoms of encephalitis include:

• Headache
• Stiff neck
• Irritability
• Fever
• Drowsiness
• Nausea and vomiting
• Confusion
• Bizarre behavior
• Paralysis
• Seizures

Treatment of encephalitis depends on what's causing it.

You may be given:

• Antiviral medicine, if a virus is causing the encephalitis
• Anti-seizure medicine
• Steroid medicine by mouth or intravenously (I.V.)
• I.V. immunoglobulin for autoimmune encephalitis
• Plasma exchange and I.V. immunoglobulins (IVIG) for autoimmune encephalitis. These treatments use special blood products. They help fight the body's abnormal immune response or clear the abnormal antibodies from the bloodstream.

You will likely need to stay in the hospital until you are stable. In mild cases, most people recover fully in 2 to 4 weeks. But more severe cases may cause long-term disability.

• Get all vaccines for common viral illnesses.
• Drain areas of water where mosquitoes can breed.
• Use insect repellent that works on mosquitoes and ticks. Wear protective clothing when in areas where mosquitoes and ticks are found.
• Be cautious around stray cats and dogs, and wild animals.
• Try not to have close contact with people who have viruses.
• Work closely with doctors to treat and manage diagnosed autoimmune disorders.

• Rest in bed until you feel better. Stay home from school or work as advised by your doctor to prevent spreading the virus to others.
• If you were taking antiviral medicines in the hospital, you may need to continue them at home. Take any medicines as directed.
• Ask your doctor before you take medicines for fever and headache. This includes ibuprofen or acetaminophen. Tell your doctor if you have chronic liver or kidney disease. Tell them if you have ever had a stomach ulcer or digestive bleeding.
• If you have a fever, drink plenty of fluids to prevent dehydration. Drink water, sports drinks, or other fluids.

Follow up with your doctor during the next week as directed by our staff. The frequency and types of professionals involved in your follow-up will depend on how sick you were, your response to treatment, and whether you are having ongoing problems.

Contact your doctor if you have any of these:

• Fever of 100.4°F (38°C) or higher that does not get better with medicine
• Headache or stiff neck doesn't get better
• Headache or stiff neck gets worse
• Not able to keep fluids down due to vomiting

Call 911 if any of the following occur:

• Increasing drowsiness, confusion, or bizarre behavior
• Weakness of an arm or leg or one side of the face
• Trouble with speaking
• Trouble seeing
• Trouble walking
• Seizure
• Fainting