Meningitis

Meningitis is an infection of the meninges (the protective membranes that surround the brain and spinal cord).

The infection is most commonly caused by bacteria or a virus, and it leads to the meninges becoming inflamed (swollen). This can damage the nerves and brain. Less common causes of meningitis are parasites and fungi.

Meningitis causes symptoms such as:

  • severe headache
  • vomiting
  • high temperature (fever) of 38ºC (100.4ºF) or over
  • stiff neck
  • sensitivity to light
  • a distinctive skin rash (although not everyone will develop this)

Symptoms can differ in young children and babies. See Meningitis - symptoms for more information.

Bacterial meningitis

Bacterial meningitis is very serious and should be treated as a medical emergency. If the bacterial infection is left untreated, it can cause severe brain damage and infect the blood (septicaemia)

In 2008 there were 255 cases of bacterial meningitis reported in Ireland. Since then the number of cases has decreased because of the MenC vaccination programme that protects against many of the bacteria that can cause meningitis.

Meningococcal group B disease is the most common cause of bacterial meningitis in Ireland. The MenB vaccine protects against Meningitis B disease. The vaccine has not yet been introduced into the Primary Childhood Immunisation Schedule but is available privately from a General Practitioner.

It is essential to know the signs and symptoms to look for and get medical help if you are worried about meningitis.

Bacterial meningitis is most common in children who are under five years of age, and in particular in babies under the age of one. It is also common among teenagers aged 15 to 19 years. 

Viral meningitis

Viral meningitis is the most common and less serious type of meningitis. It is difficult to estimate the number of cases of viral meningitis because the symptoms are often so mild that they are mistaken for flu.

Viral meningitis is most common in children and is more widespread during the summer months.

Meningitis caused by parasites or fungi

Both parasites and fungi can cause meningitis, but these type of infections are not common. Individuals with weakened immune systems may be at increased risk of these diseases.

Outlook

Viral meningitis usually gets better within a couple of weeks, with plenty of rest and painkillers for the headache.

Bacterial meningitis is treated with antibiotics (medication that treats infections caused by bacteria). Treatment will require admission to hospital, with severe cases treated in an intensive care unit so that the body's vital functions can be supported.

Meningitis caused by parasites or fungi need specific treatments (anti-parasitic or anti-fungal).

Several decades ago, almost everyone who had bacterial meningitis would die. Nowadays, deaths are mainly caused by septicaemia (blood poisoning) rather than meningitis. Meningococcal disease (the combination of meningitis and septicaemia) causes death in around one in 10 cases.

Up to a quarter of people may experience complications, such as hearing loss, after having bacterial meningitis (see Meningitis - complications).

 

Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.
Septicaemia (blood poisoning)
Septicaemia (another name for blood poisoning)refers to a bacterial infection of the blood.

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

Bacterial meningitis

Bacterial meningitis is the more serious form of the condition. The symptoms usually begin suddenly and rapidly get worse. If you suspect a case of bacterial meningitis, you should phone 999 immediately to request an ambulance.

There are some early warning signs that you may notice before the other symptoms appear.

Early warning signs

Bacterial meningitis has a number of early warning signs that can occur earlier than the other symptoms. These are:

  • pain in the muscles, joints or limbs, such as in the legs or hands
  • unusually cold hands and feet, or shivering
  • pale or blotchy skin and blue lips

The presence of a high temperature (fever) plus any of the above symptoms should be taken very seriously. Phone 999 immediately to request an ambulance.

Early symptoms

The early symptoms of bacterial meningitis are similar to those of many other conditions, and include:

  • a severe headache
  • fever (see box, left)
  • nausea (feeling sick)
  • vomiting (being sick)
  • feeling generally unwell

Later symptoms

As the condition gets worse it may cause:

  • drowsiness
  • confusion
  • seizures or fits
  • being unable to tolerate bright lights (photophobia) - this is less common in young children
  • a stiff neck - also less common in young children
  • a rapid breathing rate
  • a blotchy red rash that does not fade or change colour when you place a glass against it - the rash is not always present

Babies and young children

The symptoms of bacterial meningitis are different in babies and young children. Possible symptoms include:

  • becoming floppy and unresponsive, or stiff with jerky movements
  • becoming irritable and not wanting to be held
  • unusual crying
  • vomiting and refusing feeds
  • pale and blotchy skin
  • loss of appetite
  • staring expression
  • very sleepy with a reluctance to wake up

Some babies will develop a swelling in the soft part of their head (fontanelle).

Viral meningitis

Most people with viral meningitis will have mild flu-like symptoms, such as:

  • headaches
  • fever (see box to the left)
  • generally not feeling very well

In more severe cases of viral meningitis symptoms may include:

  • neck stiffness
  • muscle or joint pain
  • nausea (feeling sick)
  • vomiting (being sick)
  • diarrhoea (passing loose, watery stools)
  • photophobia (sensitivity to light)

Unlike bacterial meningitis, viral meningitis does not usually lead to septicaemia (blood poisoning).

Meningitis is a very serious illness but, if treated quickly, most children make a full recovery.

Fever

A fever is where you have a body temperature that is higher than usual. In general, in both adults and children, this is taken to be a temperature of 38ºC (100.4ºF) or over.

Other signs of fever include:

  • your face is hot to touch
  • you look red or flushed

Bacterial or viral meningitis?

It is only possible to distinguish between bacterial and viral meningitis by carrying out clinical tests. It is not possible to tell the difference from the symptoms alone.

Therefore, every case of suspected meningitis should be treated as a medical emergency

 

Most commonly meningitis can be caused by bacteria or a virus. Less common causes of meningitis are parasites and fungi.

Bacterial meningitis

Vaccination programmes have helped to reduce the number of different types of bacteria that can cause meningitis. However, there are currently a number of bacteria for which no effective vaccines have been developed. Some bacterial causes are described below.

Neisseria meningitidis bacteria

Neisseria meningitidis bacteria are often referred to as meningococcal bacteria. There are several different types of meningococcal bacteria called groups A, B, C, W135, Y and Z.

There is a vaccination routinely recommended in Ireland that provides protection against group C meningococcal bacteria. See the Health A-Z topic about the Men C vaccination for more information.

In Ireland, most cases of meningococcal meningitis are caused by the group B bacteria. Before the Men C vaccination programme many cases of meningococcal C disease were reported each year.

Streptococcus pneumoniae bacteria

Streptococcus pneumoniae bacteria are often referred to as pneumococcal bacteria. Pneumococcal bacteria tend to affect babies and young children because their immune system (the body's defence system) has not built up immunity (protection) to these bacteria. The elderly are also affected because they lose immunity to the bacteria as they get older.

Spreading the bacteria

The meningococcal bacteria that cause meningitis do not live long outside the body, so they are usually only spread through prolonged, close contact. Possible ways to spread the bacteria include:

  • sneezing
  • coughing
  • kissing
  • sharing utensils, such as cutlery
  • sharing personal possessions, such as a toothbrush or cigarette

As most people, particularly adults above 25, have a natural immunity to the meningococcal bacteria, most cases of bacterial meningitis are isolated (single cases). However, there is a chance of a small outbreak of cases occurring in environments where a lot of young people live close together. For example:

  • a boarding school
  • a university campus
  • a military base
  • student housing

Pneumococcal bacteria are much easier to catch than meningococcal bacteria, and they are spread through coughing and sneezing. However, in most cases they only cause mild infection, such as a middle ear infection (otitis media). Outbreaks caused by pneumococcal bacteria are uncommon.

See the Health A-Z topic about Pneumococcal infections for more information about the type of infections that these bacteria can cause.

Viral meningitis

As in the case of bacterial meningitis, vaccination programmes have successfully eliminated the threat from many viruses that used to cause viral meningitis.

For example, the measles, mumps and rubella (MMR) vaccine provides children with immunity against mumps, which was once a leading cause of viral meningitis in children. See the Health A-Z topic about the MMR vaccination for more information.

There are still a number of viruses that can cause viral meningitis. These include:

  • enteroviruses - these are a group of viruses that usually only cause a mild stomach infection, although in the past they also caused polio (a condition that can cause paralysis but is now rare as a result of successful vaccination programmes)
  • the herpes simplex virus - this can cause genital herpes and cold sores 

These viruses can be spread through:

  • coughing
  • sneezing
  • not washing your hands after they are contaminated with the virus - for example, after touching a surface or object that has the virus on it

During a meningitis infection

In most meningitis infections, bacteria or viruses spread through the blood. An infection can begin in one part of the body, such as your throat or lungs, before moving through the tissue and into the blood.

The brain is usually protected from infection by the blood-brain barrier, which is a thick membrane that filters out impurities from the blood before allowing it into the brain.

However, in some people, for reasons that are not entirely clear, the infection is able to pass through the blood-brain barrier and infect the meninges (brain membrane). The immune system responds to the infection by causing the meninges to swell in an attempt to stop the spread of infection. The swollen meninges may then damage the brain and the rest of the nervous system (nerves and spinal cord).

Bacteria or viruses can also infect the cerebrospinal fluid (CSF), which is the fluid that surrounds and supports the brain and spinal cord. An infection of the CSF can cause further swelling of the meninges, leading to increased pressure in the skull and pressing on the brain. This is known as intracranial pressure.

Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some are good for you.
Immune system
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.
Meninges
The protective membranes that surround the brain and spinal cord.

Meningitis is difficult to diagnose because it usually comes on suddenly and can be easily confused with the flu. Many of their symptoms are the same (see Meningitis - symptoms).

Seek medical attention

If you notice any of the symptoms of meningitis, particularly in a young child, seek medical help immediately.

This may mean going to the accident and emergency (A&E) department of your local hospital in the middle of the night. Do not wait for the purple rash to appear because not everyone gets a rash. Always treat a suspected case of meningitis seriously until doctors have confirmed the diagnosis.

If you are not sure if it is meningitis, you can get more information by contacting your GP.

Confirming the diagnosis

In cases of suspected meningitis, treatment will usually begin before the diagnosis has been confirmed. This is because some of the tests can take several hours to complete and it could be dangerous to delay treatment for that amount of time.

The doctors will carry out a physical examination to look for signs of meningitis or septicaemia (blood poisoning), such as a rash. They will also carry out tests to confirm the diagnosis.

Diagnostic tests for meningitis include:

  • a blood test - to check for the presence of bacteria or viruses that can cause meningitis 
  • a lumbar puncture - where a sample of cerebrospinal fluid (CSF) is taken from the base of the spine and checked for the presence of bacteria or viruses

A lumbar puncture will need to be delayed if there are signs of increased pressure on the brain. This is because removing some of the CSF could increase in pressure even more.

Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some are good for you.
Cerebrospinal fluid (CSF)
CSF is the fluid that surrounds your brain and spinal cord. It helps to support and protect the brain and spinal cord from trauma.

The tumbler test

If your child or a young adult is clearly ill and a purplish or red rash has appeared, press the side of a glass tumbler firmly against their skin. If you can see the rash through the glass, the person has septicaemia (blood poisoning).

Seek urgent medical help at the A&E department of your local hospital, or call 999 to request an ambulance.

People with suspected meningitis or septicaemia (blood poisoning) need to be admitted to hospital immediately, wherever they are.

Bacterial meningitis

Someone with bacterial meningitis will require urgent treatment in hospital. If they have severe meningitis, they may need to be treated in an intensive care unit (ICU).

Antibiotics (medication for infections caused by bacteria) will be used to treat the underlying infection. These will be given intravenously (through a vein in your arm).

At the same time you may also be given:

  • oxygen
  • intravenous fluids (through a vein)
  • steroids or other medication to help reduce the inflammation (swelling) around your brain

If the antibiotics work well, you should spend about a week in hospital, or maybe less. But if you are severely ill you may need to stay in hospital for weeks or even months.

Meningococcal disease (the combination of meningitis and septicaemia) can cause some long-term complications. See Meningitis - complications for more information.

Viral meningitis

Viral meningitis can either be:

  • severe
  • mild

The treatment for both severe and mild meningitis is described below.

Severe viral meningitis

If the symptoms of viral meningitis are severe enough to require admission to hospital, the condition will be treated in the same way as bacterial meningitis with antibiotics.

Once a diagnosis of viral meningitis has been confirmed, the antibiotics will be withdrawn. However, intravenous fluids will be continued to support the body as it recovers.

In very severe cases, where someone is in hospital with viral meningitis, anti-viral medicines may be given.

Mild viral meningitis

Most people with viral meningitis will not require hospital treatment. Viral meningitis is usually mild and can be treated at home with:

  • plenty of rest
  • painkillers for the headache
  • anti-emetics (anti-sickness) medicine for the vomiting

Most people recover within 5 to 14 days.

Infection control

Most cases of meningitis are isolated and the risk of the infection spreading is low.

However, if someone is thought to be particularly at risk of infection, they can be given a dose of antibiotics as a precautionary measure. For example, a young child who has spent a large amount of time in close contact with another child who has developed bacterial meningitis.

Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some are good for you.
Inflammation
Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.
Septicaemia (blood poisoning)
Septicaemia (another name for blood poisoning) refers to a bacterial infection of the blood.

Bacterial meningitis can place tremendous strain on the body and the brain. It is estimated that a quarter of people with meningococcal disease (the combination of meningitis and blood poisoning) will have complications. These can vary in severity from person to person, and they can be temporary or permanent.

Usually, the more severe a meningitis infection is, the greater the likelihood of complications. So complications are more common after bacterial meningitis and very rare after viral meningitis.

Possible complications include:

  • hearing loss (which may be partial or total)
  • problems with memory and concentration
  • problems with co-ordination and balance
  • learning difficulties (which may be temporary or permanent)
  • epilepsy - a condition that causes someone to have repeated fits
  • cerebral palsy - a general term for a set of conditions that affect movement and co-ordination
  • speech problems
  • vision loss (which may be partial or total)

Hearing loss

As hearing loss is the most common complication of meningitis people recovering from the condition are usually given a hearing test to assess their hearing. The test should be carried out before you are discharged or within four weeks of being well enough to have the test.

Children and young people should discuss the results of their hearing test with a paediatrician (a doctor who specialises in treating children). This should take place four to six weeks after you are discharged from hospital. If your hearing is severely affected, you may need to have cochlear implants (small devices that are inserted into your ear to improve your hearing).

See the Health A-Z topic about Hearing impairment for more information about this condition.

Gangrene

If bacteria have also entered the blood they can produce toxins (poisons) that kill healthy tissue. If the tissue damage is severe, it will die and become gangrenous.

Gangrenous tissue will need to be surgically removed (debridement). In the most severe cases, it may be necessary to amputate a whole body part, such as a:

  • finger
  • toe
  • limb

Intensive care

Being treated in intensive care for several weeks can also sometimes cause complications. Some of the common problems that people have reported after leaving an intensive care unit include:

  • feeling weak and tired
  • having a weak voice
  • feeling depressed

See the Health A-Z topic about Intensive care - recovery for more information about the problems that you may experience, and the help that is available.

Psychological effects

Having meningitis can be a traumatic experience, particularly for young children. Many people's psychological and emotional behaviour may change.

Possible psychological effects include:

  • becoming 'clingy' and needing to be near a loved one - for example, a child feel anxiety when they are not with a parent
  • bed wetting
  • disturbed sleep
  • nightmares
  • moodiness
  • aggression or irritability
  • feeling despondent (dejected or hopeless)
  • temper tantrums
  • developing a fear of doctors and hospitals

These effects should improve with time as you or your child recover, but some people may need additional therapy to cope.

Talk to your GP if you are anxious about your child's behaviour or you are having psychological complications.

Your GP may be able to refer you to the mental health services for treatment, such as counselling (a talking therapy), or they may refer your child to a childhood psychologist (a healthcare professional who specialises in the assessment and treatment of mental health conditions in children).

See the Health A-Z topic on Counselling for more information about this type of treatment.

 

Septicaemia (blood poisoning)
Septicaemia (another name for blood poisoning) refers to a bacterial infection of the blood.

 

There are a number of vaccines that can prevent many cases of viral and bacterial meningitis. They include:

Children should receive these vaccines as part of their childhood vaccination programme. Speak to your GP if you are not sure whether you or your child's vaccinations are up to date.

Older people should get the pneumococcal vaccine when they reach 65 years of age. Speak to your GP if you are not sure if you are up to date.

Some people with weakended immune systems should get additional vaccines to prevent bacteria causing meningitis.  Speak to your GP if you are not sure if you have got all the vaccines that can help you avoid infection.

Vaccines for travellers

If you are going travelling, you can be vaccinated against groups A, C, W135 and Y of the meningococcal bacteria. This vaccine may be considered if you are travelling to a high-risk area, such as some parts of Africa or the Middle East, and you are:

  • staying for longer than one month
  • backpacking
  • living with locals in rural areas
  • attending the Hajj or Umrah pilgrimages (religious journeys to Mecca, the centre of the Islamic world) in Saudi Arabia
  • doing seasonal work in the Hajj area of Saudi Arabia

See the Health A-Z topic about Travel vaccinations for more information.


Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.

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