What is meningitis?

Meningitis is an infection of the membranes (meninges) surrounding the brain and spinal cord. Meningitis can be caused by a bacterial, fungal or viral infection. Meningitis can be acute, with a quick onset of symptoms, it can be chronic, lasting a month or more, or it can be mild or aseptic. Anyone experiencing symptoms of meningitis should see a doctor immediately.

What is bacterial meningitis?

Acute bacterial meningitis is the most common form of meningitis. Approximately 80% of all cases are acute bacterial meningitis. Bacterial meningitis can be life threatening. The infection can cause the tissues around the brain to swell. This in turn interferes with blood flow and can result in paralysis or even stroke.

Who gets bacterial meningitis?

Children between the ages of 1 month and 2 years are the most susceptible to bacterial meningitis.

Adults with certain risk factors are also susceptible. You are at higher risk if you abuse alcohol, have chronic nose and ear infections, sustain a head injury or get pneumococcal pneumonia.

You are also at higher risk if you have a weakened immune system, have had your spleen removed, are on corticosteroids because of kidney failure or have a sickle cell disease.

Additionally, if you have had brain or spinal surgery or have had a widespread blood infection you are also a higher risk for bacterial meningitis.

Outbreaks of bacterial meningitis also occur in living situations where you are in close contact with others, such as college dormitories or military barracks.

What causes bacterial meningitis?

The bacteria most often responsible for bacterial meningitis are common in the environment and can also be found in your nose and respiratory system without causing any harm.

Sometimes meningitis occurs for no known reason. Other times it occurs after a head injury or after you have had an infection and your immune system is weakened.

What are the symptoms of bacterial meningitis?

You want to watch for high fever, headaches, and an inability to lower your chin to your chest due to stiffness in the neck.

In older children and adults, you may see confusion, irritability, increasing drowsiness. Seizures and stroke may occur.

In young children, the fever may cause vomiting and they may refuse to eat. Young children may become very irritable and cry. There may be seizures. Also, because the fluid around the skull may become blocked their heads may swell.

The onset of symptoms is fast, within 24 hours. If allowed to progress, you can die from bacterial meningitis.

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