What is meningitis?

The term meningitis refers to an inflammation of the protective layers surrounding the brain and spinal cord - known as the meninges - that is caused by either a bacterial or viral infection. Bacterial meningitis is generally much more serious than viral meningitis, and without appropriate antibiotic treatment is almost always fatal. However, incidences of bacterial meningitis are rapidly reducing due to the widespread use of the Hib and meningococcal vaccines.

The bacteria responsible for the condition reaches the brain by spreading through the bloodstream from an initial site of infection, most commonly the nose or throat. Almost all bacterial meningitis is caused by just three bacteria: Haemophilus, meningococcus and pneumococcus. 

Each of these is commonly found in the nose and throat of healthy people but, for reasons that are not fully understood, occasionally gets into the bloodstream.

If the body’s own defences do not stop the infection at this point, septicaemia (blood poisoning) can occur. This is potentially very dangerous and the toxins produced by the bacteria can do a great deal of damage to organs and tissues. If the infection reaches the brain, this causes meningitis, which can lead to lasting damage and even death if it is not diagnosed quickly enough and treated correctly.

What are the different types of meningitis?

Depending on the type of bacteria involved, meningitis can manifest as one of several distinct types of disease.

Meningococcal disease
Meningococcal disease is the most common form of bacterial meningitis in the UK, and is caused by the MenA, MenB, MenC, MenW and MenY bacteria. Depending on how the bacteria enters the body, it can cause multiple forms of infection: if the meninges are affected it leads to meningitis, while bacterial infections in the bloodstream can cause septicaemia, or blood poisoning.

Up to 10% of meningococcal disease cases will result in death, and many of those who recover experience long-term after-effects.

Pneumococcal meningitis
Pneumococcal meningitis is caused by a bacteria called streptococcus pneumoniae, with around 200 reported cases each year, most commonly affecting babies and young children.

Approximately 15% of cases will result in death, and 25% of survivors experience severe and disabling after-effects; however, vaccines are available in the routine UK immunisation schedule to help prevent this disease.

Hib meningitis
Hib meningitis is caused by Hib bacteria, which is also responsible for infections such as epiglottitis, septic arthritis, osteomyelitis, pericarditis, cellulitis, bronchitis and otitis media.

This disease can be fatal in around 3% of cases, but a routine vaccine available as part of the Childhood Immunisation Programme for babies has been hugely successful in preventing it, reducing cases by 98%.

Neonatal meningitis
Neonatal meningitis occurs in the first 28 days of life and is caused by many different types of organism, including group B streptococcal, E. coli and Listeria bacteria, as well as some viruses.

There are around 300 cases of neonatal bacterial meningitis each year in the UK and 10% to 12% of these cases are fatal, while up to half lead to long-term after-effects.

TB meningitis
TB meningitis is caused by the Mycobacterium tuberculosis bacteria and is most likely to affect those living in poor conditions, such as the homeless and people with other illnesses like HIV.

This infection begins in the lungs before progressing slowly into a form of meningitis. Between 15% and 30% of patients with this disease will die, with around 150 to 200 cases reported each year in the UK.

How is meningitis diagnosed?

Young children are at particular risk of meningitis because they will not have encountered the bacteria before, meaning they will have no immunity to them. In the first days and weeks of life, when immune defences are immature, the risk of meningitis is higher than at any other age. However, at this age, the bacteria usually responsible are streptococcus B, E.coli and Listeria. These are all commonly found in the mother’s lower bowel and birth canal.

For information about the tests involved in diagnosing meningitis, take a look at the NHS website.

What are the symptoms of meningitis in babies and young children?

There are various symptoms of meningitis in babies and young children, and it is important to remember that not every baby will display every symptom. Symptoms include:

• High fever, but with cold hands and feet
• Drowsiness and being unresponsive
• Rapid breathing or grunting
• Vomiting
• Unwillingness to feed
• Unwillingness to be picked up
• Blotchy skin and a red rash that does not fade if you roll a glass over it
• Seizures or convulsions
• Stiff neck
• A tense soft spot on the head

In young infants, it is often very hard to distinguish meningitis from other, less serious conditions. Part of the reason for this is that many of the tell-tale features of the disease are symptoms rather than visible signs, and a small baby cannot tell anyone that they have a headache or are distressed by the light. Also, vomiting in babies is so common that it is often not seen as significant. 

Because it is so difficult to diagnose in a young infant and because a delay in diagnosis can have such catastrophic effects, the possibility of meningitis should never be dismissed when a baby falls ill.

What are the symptoms in older children, teenagers and adults?

As with the symptoms for babies and young children, these symptoms can appear in any order and may not affect every sufferer. They include:

• Fever, but with cold hands and feet
• Irritability and confusion
• Drowsiness
• Vomiting
• Distinctive rash
• Headaches
• Muscle pains

In more advanced cases, extreme drowsiness can progress to a coma. There may also be abdominal and muscle pain, as well as a rash. This rash consists of tiny red or brown pin-prick spots that do not fade when pressed firmly with a glass tumbler. 

What is the glass test?

In instances where a rash, which is comprised of small ‘pinpricks’ that later turn into purple bruising, is present, the glass test can be used to tell if a person has meningitis. It is performed by pressing the side of a clear glass firmly against the skin. If the rash does not fade, it is a sign of meningococcal septicaemia. If this occurs, you should seek medical help immediately as it is considered a medical emergency.

What are the after-effects of meningitis?

One of the most serious aspects of meningitis is the fact that many patients are left with long-term after-effects that can often be life-changing. These include:

• Brain injury
• Deafness
• Learning difficulties
• Epilepsy
• Mood swings
• Disruptive behaviour
• Vision problems
• Headaches
• Chronic tiredness
• Memory loss and concentration problems

Additionally, the toxins released during meningitis-related septicaemia can cause damage to blood vessels, resulting in additional after-effects such as:

• Skin and tissue damage
• Amputations
• Organ failure