Definition

The brain and spinal cord are encased by layers of tissue. These layers are called the meninges. Certain viruses can cause an infection in these layers. This is called viral meningitis.

Some types can be less serious than bacterial meningitis]]> .

The Spinal Cord and Meninges

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Causes

A number of viruses can cause viral meningitis including:

• Enteroviruses
• Herpes]]> viruses
• ]]>Mumps]]>
• Varicella virus ( ]]>chickenpox]]> )
• ]]>Measles]]>
• ]]>Rubella]]> viruses
• ]]>West Nile virus]]>

Most of these are also able to cause ]]>encephalitis]]> . This is an inflammation of the brain tissue. It is a much more serious condition.

Viruses that cause meningitis can be spread in numerous ways:

• Enteroviruses are spread:
  • Via direct contact with respiratory secretions of an infected person
  • Through feces
• Other viruses (mumps, herpes, chickenpox) spread though close personal contact or through the air
• Some viruses (West Nile) that cause encephalitis are spread by insects

Risk Factors

Risk factors for viral meningitis include:

• Conditions that weaken the immune system, such as HIV infection]]> (which itself can lead to meningitis/encephalitis)
• Immunosuppressive treatments
• Crowded, unsanitary conditions
• Season: summer and early fall

Symptoms

Classic symptoms of viral meningitis include:

• High fever
• Headache
• Stiff, sore neck
• Nausea
• Vomiting
• Sensitivity to bright lights
• Sleepiness

In newborns and infants:

• Inactivity
• High fever (especially unexplained high fever)
• Irritability
• Vomiting
• Feeding poorly or refusing to eat
• Tautness or bulging of soft spots between skull bones
• Difficulty awakening

Diagnosis

The doctor will ask about your symptoms and medical history. A physical exam will be done. The doctor will focus on the nervous system. To help rule out other causes of the inflammation, such as a tumor, your doctor may order an:

• MRI scan]]> —a test that uses magnetic waves to make pictures of structures inside of the body
• ]]>CT scan]]> —a type of x-ray that uses a computer to make pictures of structures inside of the body

To rule out bacterial meningitis, the following tests may be done:

• ]]>Lumbar puncture (spinal tap)]]> —removal of fluid from the lower spinal column to be tested for bacteria (bacterial cultures)
• Other cultures—blood, urine, mucus, and/or pus from skin infections

Treatment

Treatment includes:

• Rest and fluids
• Nonsteroidal anti-inflammatory drugs
• Aspirin]]> —Note: Aspirin is not recommended for children with a current or recent viral infection
  • Check with your doctor before giving a child aspirin
• Antibiotics may be given for 2 to 3 days while waiting for bacterial cultures to be reported as negative

• IV antiviral drugs and other medications may be given

If you are diagnosed with viral meningitis, follow your doctor's instructions .

Prevention

Wash your hands often particularly:

• If you are in close contact with an infected person
• Immediately after changing the diaper of an infected infant

If you work in a childcare setting:

• Regularly wash objects and surfaces touched by children
• Use a diluted bleach solution

If you've never had measles, mumps, rubella, and chickenpox:

• Consider being vaccinated

Some forms of viral meningitis are spread by mosquito bites:

• Follow public health recommendations for reducing mosquitoes near your home
• Take steps to avoid being bitten by mosquitoes

If you are contemplating a pregnancy:

• Be sure you are protected from common diseases (eg, chickenpox)
• Avoid all contact with rodents during pregnancy:
  • Lymphocytic choriomeningitis virus can be acquired from pet hamsters, mice, or other rodents
  • If you own a rodent, consider finding another home for it while you are pregnant