Home /

Quick Facts: Brain, Spinal Cord, and Nerve Disorders /

Brain Infections /

... /

Overview of Brain Infections /

How do infections get in your brain?

What are the symptoms of brain infections?

How do doctors diagnose brain infections?

How do doctors treat brain infections?

Brain Infections

Overview of Brain Infections

Brain Abscess

Encephalitis

Rabies

ADDITIONAL CONTENT

Abortion is defined as the intentional ending of a pregnancy by surgery or drugs. Which of the following statements about abortion in the United States is most accurate?

Abortion is illegal during the 1^st trimester
Abortion is one of the most common surgical procedures done
Abortion is always unsafe, and complications are common
About 70% of pregnancies are unintended and result in elective abortion

Overview of Brain Infections

By

The Manual's Editorial Staff

Last full review/revision Sep 2020| Content last modified Sep 2020

Click here for the Professional Version

Get the full details

Brain infections are very serious and can be fatal. They can be caused by:

Viruses (most common)
Bacteria
Fungi or parasites (rare)

Infections that involve only the brain are called encephalitis. Infections that involve the layers of tissue (meninges) that cover the brain and spinal cord are called meningitis. But encephalitis can spread and cause meningitis. And sometimes meningitis spreads to cause encephalitis.

Brain infections from a virus usually affect your whole brain. Brain infections caused by bacteria sometimes cause a pocket of pus, called a brain abscess.

Infections usually start somewhere else. They can get to your brain and meninges in several ways:

From an infection nearby, such as in your teeth, sinuses, or ears
Through your blood from another part of your body
Directly from the outside, for example, through a skull fracture or during brain surgery

Infections that spread through your blood sometimes come from bug bites, particularly from mosquitoes and ticks.

Brain infections keep your brain from working properly. You often have:

Headache
Confusion and trouble thinking clearly

You may not act like yourself. Severe infections can cause seizures and make you go into a coma, have trouble breathing, and sometimes die.

Doctors usually do:

CT or MRI
Spinal tap

Doctors try to treat the cause of the infection. Antiviral drugs or antibiotics work for some infections but not all. Doctors also give medicine to relieve symptoms. If needed, they may put the person on a ventilator or give treatments to support the person's blood pressure.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version

Click here for the Professional Version

Electromyography (EMG) and Nerve Conduction Studies

Was This Page Helpful?

Brain Abscess

Overview of Brain Infections

Overview of Brain Dysfunction

Parasitic Brain Infections

Merck and the Merck Manuals

Merck & Co., Inc., Kenilworth, NJ, USA is a global healthcare leader working to help the world be well. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world. The Merck Manual was first published in 1899 as a service to the community. The legacy of this great resource continues as the Merck Manual in the US and Canada and the MSD Manual outside of North America. Learn more about our commitment to Global Medical Knowledge.

This site complies with the HONcode standard for trustworthy health information:
verify here.

TOP