Meningitis is an inflammation of the lining that surrounds the brain and spinal cord, known as the meninges. The condition can be caused by many different organisms, including bacteria, viruses, fungi and amoebae.
Some bacteria that cause meningitis can also enter the blood stream and cause septicaemia, which is also known as blood poisoning (sepsis). Bacterial meningitis and septicaemia can both kill within hours of infection. Survivors may be left with a range of complications that dramatically alter their lives.
Bacterial meningitis and septicaemia have a number of symptoms that are similar, as well as others that are disease-specific. Both conditions can be hard to identify, as the initial symptoms are similar to those of many mild illnesses. Patients present themselves initially with a fever, vomiting, headache and feeling unwell, although symptoms can appear in any order.
In both meningitis and septicaemia patients, a rash that does not disappear under pressure, for example when a glass is pressed against it (see Tumbler Test), may appear anywhere on the body and they may be sleepy, vacant or difficult to wake and confused or delirious. Meningitis patients can also experience a stiff neck and discomfort to bright lights (both less common in young children), as well as seizures. Septicaemia patients can suffer from limb, joint and muscle pain; cold hands and feet; shivering; pale or mottled skin; and fast breathing/breathlessness.
In babies and toddlers, other symptoms can include a refusal to eat or feed; irritability and not wanting to be held or touched; a stiff body with jerky movements or floppy and lifeless; a high-pitched or moaning cry; and the fontanelle (soft spot on babies' heads) may be tense or bulging. Some symptoms may not occur at all, for example the rash can be late to appear or be completely absent. Sometimes symptoms develop slowly yet the person can still become ill very quickly.
Viral meningitis can be very unpleasant but it is almost never life-threatening and most people make a rapid and full recovery. However, bacterial meningitis is far more serious.
Bacterial meningitis can be caused by many different bacteria. One of the most common causes is the meningococcal bacterium, which can also enter the bloodstream and cause septicaemia. Most people who become infected with meningococcal bacteria have symptoms of both meningitis and septicaemia, collectively known as meningococcal disease. When septicaemia occurs without meningitis, it is even more life-threatening.
There are five serogroups of the meningococcal bacteria which can cause the vast majority of meningitis and septicaemia cases; they are meningococcal serogroups A, B, C, W-135 and Y. Serogroups B and C are the most common cause of disease in Europe and there are a number of vaccines available that provide protection against several meningococcal serogroups, however, scientistsare still pursuing the development of a global vaccine targeting serogroup B.
The conjugated MenC vaccine, for example, has dramatically reduced meningococcal disease caused by serogroup C of the meningococcal bacteria in vaccinated individuals and the wider population due to herd immunity. Tetravalent vaccines protecting against serogroups A, C, W-135 and Y forms of the disease have also been developed, and promise to reduce the disease burden further. Other equally serious forms of the diseases are not yet preventable through vaccination, although a number of vaccines are in development, including MenB vaccines, which it is hoped will be effective against serogroup B of the meningococcal bacteria, the most common cause of meningitis in the UK and Western Europe. Until medical research delivers these new vaccines, public awareness of both meningitis and septicaemia and their symptoms is vital, as immediate medical treatment is essential if infection is suspected.
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