Meningococcal infection is caused by the meningococcal bacteria (Neisseria meningitidis). The bacteria can cause life-threatening meningitis or septicaemia, or a combination of these diseases.

In the case of meningitis, bacteria attack the lining between the brain and skull called the meninges. It can cause severe brain damage and is fatal in 50% of cases if untreated.

There are several strains or serogroups of meningococcal bacteria B, C, A, Y and W135. Meningitis serogroup B (MenB) accounts for almost all cases in the UK. Serogroup C (MenC) used to account for one third of all cases however now, through the introduction of routine vaccination, almost all cases are prevented.

The UK was the first country in the world to introduce meningococcal serogroup C conjugate (MenC) vaccination. The immunisation programme started in November 1999 for everybody up to the age of 18 years, and to all first year university students. This has since been extended to include everybody less than 25 years of age.

The majority of meningococcal infections occur in infants under five years of age, with a peak incidence in those under 1 year of age. There is a smaller, secondary peak in incidence in young adults aged between 15-19 years of age. Immunisation has shown a significant reduction of cases caused by MenC within the targeted age groups.

The information outlined above reflect current NHS Choices recommendations

Meningitis: What is it?

Meningitis is inflammation of the protective layers or lining around the brain and spinal cord. These layers are often called ‘meninges’ and the fluid around them ‘cerebral spinal fluid’ or CSF.

Viruses, bacteria or fungi can cause meningitis. While viral meningitis is a serious illness, it is rarely life-threatening and the majority of people make a full recovery.

Classic symptoms of meningitis include severe headaches, dislike of bright lights (photophobia) and neck stiffness (less common in young children). Other symptoms include nausea and vomiting, fever, confusion and drowsiness, a rash and seizures.

Bacterial meningitis can be life-threatening, particularly if it is not recognised and treated immediately. It is important to know what the symptoms of meningitis are, particularly in children, and what you should do about it.

Meningitis should be treated as a medical emergency because bacterial meningitis can lead to septicaemia, which can be fatal.

Trust your instincts. If your GP is unavailable you should go straight to the hospital or call an ambulance.