Meningitis is the inflammation of the membranes (meninges) and the cerebrospinal fluids that surround the brain and the spinal cord and it is most commonly the result of a spreading infection. In most instances, meningitis is caused by a viral infection but in some cases, bacterial and fungal infections can also result in meningitis.
Types of Meningitis
Although viral meningitis occurs most frequently, it tends to be mild and usually clears up within two weeks without any medical intervention, or antiviral medications may be prescribed. The great majority (approximately 90 percent) of viral meningitis cases are caused by a group of viruses known as enteroviruses while the rest are caused by the same viruses which are credited with causing mumps, herpes and the West Nile virus. These viruses are most prevalent during the late summer or early fall.
Bacterial meningitis is also known as the acute bacterial meningitis and it is the most severe of all meningitis cases. Acute bacterial meningitis most often occurs when bacteria enters the brain and the spinal cord through the bloodstream but it can also occur by a direct attack on the meninges when an ear or a sinus infection is present or due to a skull fracture. There are a number of different bacteria that are known to cause acute bacterial meningitis and they are:
- The most common is the streptococcus pneumonia (pneumococcus) which can also cause pneumonia as well as ear and sinus infections.
- The most contagious and can lead to dangerous epidemics is the neisseria meningitides (meningococcus) which often comes through the bloodstream from an upper respiratory infection.
- The Haemophilus influenza (haemophilus) has been greatly reduced in the United States because of the Hib vaccine.
- Listeria monocytogenes (listeria) is a common bacteria which is found just about everywhere. Except for pregnant women, infants and the elderly; most healthy adults are resistant to them.
Delayed treatments with antibiotics of bacterial meningitis will increase the risk of permanent brain damage and possible death.
Fungal meningitis is also known as the cryptococcal meningitis and it can be life threatening. Thankfully its occurrence is quite rare and mostly affects people with compromised immune systems such as in cases of AIDS.
Chronic meningitis is very rare and it occurs when the membranes and fluids surrounding the brain are attacked by slow-growing organisms.
Other Causes of Meningitis
In some case, meningitis can be caused by allergies to various drugs, certain types of cancers as well as lupus or other inflammatory diseases.
Symptoms of Meningitis
Regardless of the causes, the symptoms of meningitis seem to be similar although their severity may vary. In adults and older children the symptoms are as follows:
- Severe headaches
- High fever
- Stiff neck
- Sensitivity to light
- Mental confusion
- Skin rash
- Sore throat
- Joint aches
- Sleepiness or difficulty waking up
- Disinterest in drinking or eating
In infants, the symptoms are:
- Stiffness of the neck and the entire body
- Swelling of the soft spot at the crown of the infant’s head (fontanel)
- Relentless crying
- Sleeping more than usual
- Disinterest in feeding
- High fever