Pneumococcal meningitis

Pneumococcal meningitis is caused by the bacterium Streptococcus pneumoniae, commonly called the pneumococcus.

There are over 95 strains (or serotypes), but not all of these cause disease. The pneumococcus can also cause other serious illnesses including pneumonia, septicaemia* and septic arthritis, and other less serious illnesses including otitis media and sinusitis. Together these are known as pneumococcal disease.

There are vaccines to protect against some, but not all, strains of pneumococcal bacteria. Although most people will make a good recovery, some will be left with life-changing after-effects and some will die.

The facts

• Most cases occur in babies and young children under 18 months of age
• The elderly and people with conditions that affect their immune systems are also at increased risk
• Although most people will make a good recovery, 30% of those who survive pneumococcal meningitis can be left with severe and disabling after-effects
• There are vaccines available in the UK routine immunisation schedule to help prevent pneumococcal disease in the UK

Download our pneumococcal fact sheet.

How is it caused?

• Pneumococcal meningitis is caused by a bacteria called streptococcus pneumoniae. There are over 95 strains (or serotypes), but only a minority commonly cause disease.
• Pneumococcal bacteria can be carried harmlessly in the back of the throat by both adults and children
• Virtually all children will become carriers at one time or another. Carriage of bacteria helps us to build natural immunity
• Bacteria are passed from person to person by coughing, sneezing and intimate kissing
• When the pneumococcus invades, it can overcome the body’s defences and lead to infection
• Most of the bacteria are transferred to the meninges via the bloodstream
• When the bacteria infect the meninges, the blood vessels in the lining of the brain are damaged
• This allows the bacteria to break through and infect the cerebrospinal fluid (CSF). The meninges then become inflamed and pressure around the brain can cause nerve damage
• Pneumococcal meningitis may occur following head injury and damage to the meninges; on rare occasions this may be recurrent
• The pneumococcus can also cause other serious infections such as pneumonia, blood poisoning and septic arthritis, and less serious infections such as otitis media, glue ear and sinusitis. Together these are known as pneumococcal disease or pneumococcal infection