About 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?
High fever, headache, and stiff neck are common symptoms of meningitis in anyone
over the age of 2 years. These symptoms can develop over several hours, or they
may take 1 to 2 days. Other symptoms may include nausea, vomiting, discomfort
looking into bright lights, confusion, and sleepiness. In newborns and small
infants, the classic symptoms of fever, headache, and neck stiffness may be
absent or difficult to detect, and the infant may only appear slow or inactive,
or be irritable, have vomiting, or be feeding poorly. As the disease progresses,
patients of any age may have seizures.
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 of 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. 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. College freshman, especially those who live in
dormitories are at higher risk for meningococcal disease and should be educated
about the availability of a safe and effective vaccine which can decrease their
risk. 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 1 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.
There are vaccines to prevent meningitis due to S. pneumoniae (also
called pneumococcal meningitis) which can also prevent other forms of infection
due to S. pneumoniae. The pneumococcal polysaccharide vaccine is
recommended for all persons over 65 years of age and younger persons at least 2
years old with certain chronic medical problems. There is a newly licensed
vaccine (pneumococcal conjugate vaccine) that appears to be effective in infants
for the prevention of pneumococcal infections and is routinely recommended for
all children greater than 2 years of age.
Please refer to the
CDC website for more information
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