Meningitis

Centers for Disease Control and Prevention Recommendation for Travelers

Overseas travelers should check to see if meningococcal vaccine is recommended for their destination, as some countries have large epidemics of meningococcal meningitis.

Travelers should receive the vaccine at least one week before departure.

Meningitis

What is meningitis?

Meningitis is an inflammation of the meninges, the membranes that surround the brain. There are three meninges:

dura mater - the outside membrane that adheres to the inside of the skull
arachnoid - the middle membrane
pia mater - the innermost membrane, which adheres to the brain

What are the causes of meningitis?

There are two distinct types of meningitis:

viral - caused by a virus

Viral meningitis is more common than bacterial, although rarely life threatening. Viral meningitis can be caused by different viruses, and is spread between people by coughing or sneezing, or through poor hygiene. Other germs can be found in sewage polluted water.
Viral meningitis cannot be helped by antibiotics. Recovery is normally complete, but headaches, tiredness, and depression may persist.

bacterial - caused by a bacterium

Bacterial meningitis, although rare, may be fatal.
Bacteria may be spread through the exchange of respiratory and throat secretions, such as coughing and kissing, but they cannot live outside the body for long. They cannot be picked up from water supplies, swimming pools, buildings, etc.
Many species of bacteria can cause meningitis, but three types account for about 80 percent of cases:
- neisseria meningitidis (meningococcus) Meningococcus is found in the nasopharynx of about 5 percent of the population and is spread by respiratory droplets and close contact. For unknown reasons, only a small fraction of carriers develop meningitis. Meningococcal meningitis occurs most often in the first year of life, but may also occur in closed populations, such as schools.
- haemophilus influenzae type b
  Haemophilus influenzae type b accounts for most meningitis in children more than one month old, but usually not in adults unless there is a predisposing factor such as head trauma or a compromised immune system. Vaccines against this type are given to children as part of a routine vaccination program.
- streptococcus pneumoniae (pneumococcus)
  Pneumococcus is the most common cause of adult meningitis. Those at high risk may include persons with chronic ear infections, sinus infections, closed head injury, recurrent meningitis, and pneumococcal pneumonia.
- other

How does the infection reach the brain?

There are several ways that the infection can reach the brain, including:

through the bloodstream from another infected part of the body
through the bones of the skull from infected sinuses or inner ears
from a head injury, such as a fractured skull or penetrating wound
after surgery or extended hospitalization
a weakened immune system
as a result of chronic kidney failure

What are the symptoms of meningitis?

The following are the most common symptoms of meningitis. However, each individual may experience symptoms differently. Symptoms may include:

fever
headache
nausea and vomiting
stiff neck
photophobia (low tolerance to bright light)
confusion
joint aches or pains
drowsiness
seizures
loss of appetite
irritability

Symptoms for children may also include:

fever
high pitched cry
pale, blotchy skin color
not wanting to eat
vomiting
fretful and fussy
arching back
difficult to wake

It is important to note that these symptoms may not occur all at once, nor in everyone who contracts meningitis. The symptoms of meningitis may resemble other conditions or medical problems. Consult a physician for diagnosis.

How is meningitis diagnosed?

Early diagnosis is important so that appropriate treatment can be started immediately. The diagnosis of meningitis is usually made by taking a sample of spinal fluid obtained by performing a spinal tap. The sample of spinal fluid is analyzed in the laboratory and the type of bacteria is identified.

Treatment for meningitis:

There are many forms and degrees of meningitis. Treating it depends on the type of bacterium or virus that causes the infection. Specific treatment will be determined by your physician based on:

your overall health and medical history
extent of the disease
your tolerance for specific medications, procedures, or therapies
expectations for the course of the disease
your opinion or preference

Generally, antibiotics are used to treat bacterial meningitis, and may also prescribed for immediate family members or others who are in very close contact with the patient. Antibiotics are not used for viral meningitis.

In a 2002 study, researchers found that administering a steroid in addition to antibiotics reduces the risk of death by as much as 50 percent in cases where the meningitis was caused by the Pneumococcus bacteria. The Pneumococcus bacteria account for 30 percent to 40 percent of bacterial meningitis. In addition, fewer patients suffered serious complications of their infection if treated with both the antibiotics and the steroid. The steroid, dexamethasone, when given with antibiotics, also reduces hearing loss in children associated with the infection. The steroid-antibiotics combination also appears effective for bacterial meningitis caused by the Meningococcus bacteria, but results were not conclusive.

How is meningitis prevented?

There is a meningococcal vaccine that is currently only used for high-risk groups. Immunization for the bacteria is not widespread due to its uncommon occurrence. Individuals who may require immunization include the following:

asplenic children - children without a spleen
college students - immunization of college students is recommended by the American College Health Association
military recruits
individuals who are traveling to countries where the incidence of meningococcal infectious is higher (parts of Africa)
family members or those in close contact of individuals with meningitis, if the individual has the following type of bacterial meningitis:
- H. influenzae type b
- Neisseria meningitidis (meningococcal)

If you have questions regarding prevention, discuss this with your physician.