What is meningitis?
Meningitis is an inflammation of the linings of the brain and spinal cord caused by either viruses or bacteria.
Viral meningitis is more common than bacterial meningitis and usually occurs in late spring and summer. Signs and symptoms of viral meningitis may include stiff neck, headache, nausea, vomiting, and rash. Most cases of viral meningitis run a short, uneventful course. Since the causative agent is a virus, antibiotics are not effective. Persons who have had contact with an individual with viral meningitis do not require any treatment.
Bacterial meningitis occurs rarely and sporadically throughout the year, although outbreaks tend to occur in late winter and early spring. Bacterial meningitis in college-aged students is most likely caused by Neisseria meningitidis or Streptococcus pneumoniae. Meningococcal infection may also cause a bloodstream infection resulting in high fever, rash, and sometimes shock. Because meningococcal meningitis can cause grave illness and rapidly progress to death, it requires early diagnosis and treatment. In contrast to viral meningitis, persons who have had intimate contact with a case require prophylactic therapy. Untreated meningococcal disease can be fatal.
How does meningococcal disease occur?
Approximately 10% of the general population carry meningococcal bacteria in the nose and throat in a harmless state. This carrier state may last for days or months before spontaneously disappearing, and it seems to give persons who harbor the bacteria in their upper respiratory tracts some protection from developing meningococcal disease.
During meningococcal disease outbreaks, the percentage of people carrying the bacterium may approach 95%, yet the percentage of people who develop meningococcal disease is less than 1%. This low occurrence of disease following exposure suggests that a persons' own immune system, in addition to bacterial factors, plays a key role in disease development.
Meningococcal bacteria usually cannot live for more than a few minutes outside the body. As a result, the bacteria are not easily transmitted in water supplies, swimming pools, or by routine contact with an infected person in a classroom, dining room, bar, rest room, etc.
Roommates, friends, spouses, and children who have had intimate contact with the oral secretions of a person diagnosed with meningococcal disease are at risk for contracting the disease and should receive prophylactic medication immediately. Examples of such contact include kissing, sharing eating utensils or drinking cups, and being exposed to droplet contamination from the nose or throat.
How many cases of meningococcal disease occur each year?
The annual incidence of meningococcal disease in the United States is about 1 case per 100,000 population. In Virginia there is an average of 60 cases per year, which comprises all age groups. The case fatality rate is approximately 12%.
Can meningococcal disease be mistaken for other health problems?
Meningococcal disease is potentially dangerous because it is relatively rare and can be mistaken for other conditions. The possibility of having meningitis may not be considered by someone who feels ill, and early signs and symptoms may be ignored. A person may have symptoms suggestive of a minor cold or flu for a few days before experiencing a rapid progression to severe meningococcal disease.
What are the signs and symptoms of meningococcal disease?
Understanding the characteristic signs and symptoms of meningococcal disease is critical and possibly lifesaving.
Common early symptoms of meningococcal meningitis include fever, severe sudden headache accompanied by mental status changes (e.g. malaise, lethargy), and neck stiffness. Meningococcal bloodstream infection (meningococcemia) presents similarly but with no headache or stiff neck. A rash may begin as a flat, red eruption, mainly on the arms and legs. It may then evolve into a rash of small dots that do not change with pressure (petechiae). New petechiae can form rapidly, even while the patient is being examined.
What is the treatment for meningococcal disease exposure?
Meningococcal disease can be rapidly progressive. With early diagnosis and treatment, however, the likelihood of full recovery is increased.
Early recognition, performance of a lumbar puncture (spinal tap), and prompt initiation of antimicrobial therapy are crucial.
The use of such prophylactic antibiotics as ciprofloxacin or rifampin is recommended for those who may have been exposed to a person diagnosed with meningococcal disease. Anyone who suspects possible exposure should consult a physician immediately. Prophylactic antibiotics may also be prescribed for asymptomatic meningococcus carriers. A bacterial culture taken from the nose is required for confirmation of N. meningitidis carrier status.
As an adjunct to appropriate antibiotic chemoprophylaxis, immunization against the meningococcus bacterium may be recommended when an outbreak (defined as three cases of the same type within a 3-month period) of meningococcal disease has occurred in a community. It is important to note that meningococcal vaccine should not be used in place of chemoprophylaxis for those exposed to an infected person; the protection from immunization is too slowly generated in this situation.
Meningococcal Meningitis Vaccine:
Immunization against the bacterium N. meningitidis may be recommended for persons over 2 years of age if they are members of a population that is experiencing an outbreak of meningococcal disease, e.g., students at a university where an outbreak has occurred.
Numerous studies have demonstrated the immunogenicity and clinical efficacy of meningococcal vaccines. Although protection probably persists in schoolchildren and adults for at least 3 years, the exact timing for a booster has not been determined. As with any vaccine, vaccination may not protect 100% of all susceptible individuals. Contact your university health center to determine if vaccination is appropriate for you.
Adverse reactions to meningococcal vaccine are mild and infrequent, consisting primarily of redness and pain at the injection site that may last 1 to 2 days. Rarely, fever of short duration may occur.
Although there is no public health recommendation for universal immunization at this time, there are special situations, such as travel abroad, where it may be indicated.
How can one reduce the risk of contracting meningococcal disease?
Maximize your body's own immune system response. A lifestyle that includes a balanced diet, adequate sleep, exercise, and the avoidance of excessive stress is very important. Avoiding upper respiratory tract infections and inhalation of cigarette smoke may help to protect from invasive disease. Everyone should be sensitive to public health measures that decrease exposure to oral secretions, such as covering one's mouth when coughing or sneezing and washing hands after contact with oral secretions.
Two recent potential outbreaks occurred because of drinking directly from keg spigots and sharing cups at large parties. Avoidance of such behavior and refusing to eat or drink at parties where such activities are occurring will reduce your risk of meningococcal disease.