Viral Meningitis

Meningitis is an infection of the thin layer of tissue that covers your brain and spinal cord. This layer of tissue is called the meninges. In viral meningitis, the infection is caused by a virus. Viral meningitis isn't usually as dangerous as meningitis caused by bacteria (bacterial meningitis).

• Viral meningitis usually begins with fever, feeling ill, headache, and muscle aches

• Later, your headache gets worse, and you may have a stiff neck

• Doctors suspect viral meningitis based on your symptoms and the results of a spinal tap

• If you have meningitis caused by HIV or herpesvirus, you're treated with medicines for those viruses, but there are no medicines that treat most types of viral meningitis

• Most people with viral meningitis feel better in a few weeks

Many different viruses can cause viral meningitis, including:

• Stomach viruses (enteroviruses)—these are the most common cause

• Herpesvirus, particularly genital herpes

• Viruses carried by mosquitoes (arboviruses such as West Nile virus)

• Lymphocytic choriomeningitis virus, carried by infected mice or pet hamsters

• HIV

You can get the viruses that cause viral meningitis in several ways, depending on which virus is the cause:

• Touching contaminated stool (poop) which can happen when infected people swim in a public swimming pool or don’t wash their hands after using the bathroom

• Sex or other genital contact with an infected person

• A bite from an insect, such as a mosquito

• Breathing in the virus in the air

• Touching dust or food with urine or stool on it from infected mice or pet hamsters

• Sharing needles

Symptoms may resemble those of bacterial meningitis but are usually milder and progress more slowly. At first, you may have no symptoms or symptoms similar to a cold or stomach virus, such as:

• Fever

• Cough

• Muscle aches

• Throwing up

• Not feeling hungry

Later, you’ll have:

• Fever

• Headache

• Stiff neck that makes you unable to touch your chin to your chest or causes pain when you try—moving your head in other directions may not hurt as much

Most people, but not everyone, with herpes meningitis will also have herpes sores on their genitals.

Doctors do tests to look for viruses in the fluid surrounding your brain and spinal cord (spinal fluid). To get the spinal fluid, doctors do a:

• Spinal tap (lumbar puncture)

In a spinal tap, doctors put a long, thin needle in your lower back. They take out a little spinal fluid for testing. Before doing the spinal tap, doctors sometimes do an MRI (magnetic resonance imaging) or CT (computed tomography) scan.

Doctors will also:

• Do blood tests for signs of a viral infection

How a Spinal Tap Is Done

Spinal fluid flows through a channel between the middle and inner layer of tissues (meninges) that cover the brain and spinal cord. To remove a sample of this fluid, a doctor inserts a small, hollow needle between two bones (vertebrae) in the lower spine, below the point where the spinal cord ends. Usually, people lie on their side with their knees curled to their chest. This position widens the space between the vertebrae, so that the doctor can avoid hitting the bones when the needle is inserted. Doctors collect spinal fluid in test tubes and send it to a lab for testing.

Most people with viral meningitis don't need anti-virus medicine, because they'll get better within a few weeks with or without treatment. Sometimes, recovery is slow, and it can take a few months to feel better.