What
You Need to Know About:
Meningitis
What
is meningitis?
Meningitis is an infection of the
fluid of a person's spinal cord and
the fluid that surrounds the brain.
People sometimes refer to it as spinal
meningitis. Meningitis is usually
caused by a viral or bacterial infection.
Knowing whether meningitis is caused
by a virus or bacterium is important
because the severity of illness and
the treatment differ. Viral meningitis
is generally less severe and resolves
without specific treatment, while
bacterial meningitis can be quite
severe and may result in brain damage,
hearing loss, or learning disability.
For bacterial meningitis, it is also
important to know which type of bacteria
is causing the meningitis because
antibiotics can prevent some types
from spreading and infecting other
people. Before the 1990s, Haemophilus
influenzae type b (Hib) was the leading
cause of bacterial meningitis, but
new vaccines being given to all children
as part of their routine immunizations have
reduced the occurrence of invasive
disease due to H. influenzae.
Today, Streptococcus pneumoniae and Neisseria
meningitidis are the leading
causes of bacterial meningitis.
What
are the signs and symptoms
of meningitis?
Common
Triad of symptoms:
How
is meningitis diagnosed?
Early diagnosis and treatment are
very important. If symptoms occur,
the patient should see a doctor immediately.
The diagnosis is usually made by
growing bacteria from a sample of
spinal fluid. The spinal fluid is
obtained by performing a spinal tap,
in which a needle is inserted into
an area in the lower back where fluid
in the spinal canal is readily accessible.
Identification of the type of bacteria
responsible is important for selection
of correct antibiotics.
Can
meningitis be treated?
Bacterial meningitis can be treated
with a number of effective antibiotics.
It is important, however, that treatment
be started early in the course of
the disease. Appropriate antibiotic
treatment of most common types of
bacterial meningitis should reduce
the risk of dying from meningitis
to below 15%, although the risk is
higher among the elderly.
Is
meningitis contagious?
Yes, some forms are bacterial meningitis
are contagious. The bacteria are
spread through the exchange of respiratory
and throat secretions (i.e., coughing,
kissing). Fortunately, none of the
bacteria that cause meningitis are
as contagious as things like the
common cold or the flu, and they
are not spread by casual contact
or by simply breathing the air where
a person with meningitis has been.
However,
sometimes the bacteria that cause
meningitis have spread to other
people who have had close or
prolonged contact with a patient
with meningitis caused by Neisseria
meningitidis (also called
meningococcal meningitis) or
Hib. People in the same household
or day-care center, or anyone
with direct contact with a patient's
oral secretions (such as a boyfriend
or girlfriend) would be considered
at increased risk of acquiring
the infection. People who qualify
as close contacts of a person
with meningitis caused by N.
meningitidis should receive
antibiotics to prevent them from
getting the disease. Antibiotics
for contacts of a person with
Hib meningitis disease are no
longer recommended if all contacts
4 years of age or younger are
fully vaccinated against Hib
disease (see below).
Are
there vaccines against meningitis?
Yes, there are vaccines against Hib
and against some strains of N.
meningitidis and many types of Streptococcus
pneumoniae. The vaccines against
Hib are very safe and highly effective.
There is also a vaccine that protects
against four strains of N. meningitidis,
but it is not routinely used in the
United States and is not effective
in children under 18 months of age.
The vaccine against N. meningitidis is
sometimes used to control outbreaks
of some types of meningococcal meningitis
in the United States. Meningitis
cases should be reported to state
or local health departments to assure
follow-up of close contacts and recognize
outbreaks. Although large epidemics
of meningococcal meningitis do not
occur in the United States, some
countries experience large, periodic
epidemics. Overseas travelers should
check to see if meningococcal vaccine
is recommended for their destination.
Travelers should receive the vaccine
at least one week before departure,
if possible. Information on areas
for which meningococcal vaccine is
recommended can be obtained by calling
the Centers for Disease Control and
Prevention at (404)-332-4565.
A
vaccine to prevent meningitis
due to S. pneumoniae (also
called pneumococcal meningitis)
can also prevent other forms
of infection due to S. pneumoniae.
The pneumococcal vaccine is not
effective in children under 2
years of age but is recommended
for all persons over 65 years
of age and younger persons with
certain chronic medical problems.
Update
from October 20, 1999 Press
Release:
The Advisory Committee on Immunization
Practices (ACIP) has modified its
guidelines for use of the polysaccharide
meningococcal vaccine to prevent
bacterial meningitis, particularly
for college freshmen who live in
dormitories, a group found to be
at a modestly increased risk of meningococcal
disease relative to other persons
their age.
Information supplied by
the Centers for Disease Control
and Prevention-- Revised 2002