Meningococcal disease is a serious infection caused by a bacterium called Neisseria meningitidis. It occurs when these bacteria, which can live harmlessly in the nose and throat of healthy people, invade the tissues or bloodstream of the body. A common presentation of invasive meningococcal disease is meningitis.
Meningitis is an inflammation of the lining surrounding the brain and spinal cord. Several different organisms such as bacteria and viruses can cause this condition.
Viral meningitis is more common and usually occurs in the late summer and early fall. Sometimes, abdominal discomfort, chest pain, or a rash will be present. The central nervous system is involved with possible alteration of consciousness or paralysis; however, these more serious conditions are infrequent. Most cases of viral meningitis run a short, uneventful course. Since this is a virus (like the common cold), antibiotics are not effective. Likewise, persons who have had contact with viral meningitis patients do not require any treatment.
Bacterial meningitis is a rare disease, but can be very serious and requires treatment with antibiotics. It can occur sporadically throughout the year.
One form of bacterial meningitis is meningococcal meningitis. This form can cause very grave illness. It requires early diagnosis and treatment. Untreated meningococcal disease can be fatal.
Meningococcal bacteria are spread from person to person by direct contact with an infected person's oral or nasal secretions (for example, respiratory droplets or saliva).
Approximately 5% to 10% of the general population carries the meningococcal bacteria in the nose and throat in a harmless state. This carrier state may last for days or months and seems to give those individuals who harbor meningococci in their upper respiratory tract some protection from actually developing the disease state.
Fortunately, very few people ever develop invasive disease even if they are carriers. This low occurrence of illness after exposure suggests that an individual's health status (the strength or weakness of the immune system), rather than bacterial factors, plays an important role in determining who may get sick.
Meningococcal bacteria cannot live for more than a few minutes outside the body. They are not transmitted in water supplies, swimming pools, or by routine contact in classrooms, restaurants, bars, restrooms, etc., where an infected individual has been. Friends, classmates or children who are not directly exposed to an ill person are not at risk and do not require any treatment.
Persons who have had recent intimate or direct exposure to someone with meningococcal disease may be at increased risk for contracting meningococcal disease and should receive prophylactic medication. Intimate or direct exposure is defined as kissing, sharing eating utensils or glassware, or by droplet contamination with nose or throat secretions from the infected individual.
The annual occurrence rate of meningococcal disease in the United States is stable at 1 to 3 per 100,000. About 10% of cases result in a fatality, with early recognition and treatment being crucial variables for a good prognosis.
Meningococcal disease can be particularly dangerous for two fundamental reasons:
In instances when the meningococcal bacteria invade the bloodstream, it can be carried to other organs including the eyes, heart, lungs, and the central nervous system (brain and spinal cord).
Meningococcal meningitis can cause an individual to become very ill. Understanding the characteristic symptoms and signs is critical and could be lifesaving.
Consult with a physician or go to an emergency room immediately if you have a fever greater than 101°F AND a severe sudden headache accompanied by mental changes, neck/back stiffness, or rashes.
People who have been exposed to the saliva or oral secretions (as defined above) of a person with meningococcal disease may need to take antibiotics to prevent spread of the infection. The purpose of the antibiotics is to eliminate the meningococcal bacteria from the throat (carrier state). People who have not had direct exposure to oral secretions do not need to be treated.
The majority of patients who are diagnosed early in the course of meningitis illness can be effectively treated with antibiotics and experience complete recovery. Occasionally, a meningococcal infection is overwhelming and defies prompt medical treatment.
A lifestyle that helps keep the immune system as strong as possible with a balanced diet, adequate sleep and rest, appropriate exercise and the avoidance of excessive stress may be important. Avoiding respiratory illness and tobacco smoke may help to protect from invasive disease. Research suggests that the host's health status and ability to resist disease, rather than bacterial factors, play an important role in determining who becomes ill with meningococcal meningitis. A vaccine for meningococcal meningitis is also available but provides only limited protection.