What is meningitis?
Meningitis is a bacterial, viral or fungal infection that can cause inflammation of the protective membranes that line the brain (the meninges).
Causes of meningitis
Meningitis can be bacterial, viral or sometimes fungal, although bacterial meningitis (caused by the meningococcal bacteria) is more serious than viral or fungal meningitis and requires rapid treatment. The infection can pass through the brain's natural barrier and infect the meninges, causing them to swell as they attempt to stop the infection from spreading. Meningitis can also infect the cerebrospinal fluid (CSF), leading to a rise in intracranial pressure. Inflammation and increased pressure around the brain can cause serious injury if left untreated.
Diagnosis and treatment of meningitis
Meningitis can be recognised by a rapid onset of flu-like symptoms and a characteristic purple rash, although the rash does not always appear. Tests to diagnose meningitis can take a number of hours to complete, so treatment will usually be offered immediately if meningitis is suspected. A diagnosis can also be made using a blood test, lumbar puncture, a CT scan or a chest X-ray. Antibiotics are used to treat bacterial meningitis and serious viral meningitis. Mild viral meningitis can usually be treated at home with plenty of rest.