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- Meningococcemia facts
- What is meningococcemia?
- What causes meningococcemia?
- What are risk factors for meningococcemia?
- What are symptoms and signs of meningococcemia?
- How is meningococcemia diagnosed?
- What is the treatment for meningococcemia?
- What is the prognosis of meningococcemia?
- Is it possible to prevent meningococcemia?
- Where can people find more information on meningococcemia?
What are risk factors for meningococcemia?
Children and adolescents 5 to 19 years of age are at highest risk for meningococcemia. Newborns acquire antibodies from their mothers via the placenta, although these antibodies fade after a few weeks or months. Toddlers are not immune, and there have been several exposures in day-care settings. As children age, they gradually gain immunity to meningococcal strains by coming into contact with milder strains of the bacteria. However, because this immunity is imperfect, it is still possible for adults to get meningococcemia.
The immune system is critical in fighting off the bacteria. Patients who have a history of a specific genetic deficiency in the complement system are at high risk for severe disease. The spleen is also needed for an effective immune response, so people are at higher risk for severe disease if they have had their spleens taken out or have spleens that function poorly.
People who have been in close contact with an infected patient are at increased risk to acquire the disease themselves. People who live together in close quarters such as military barracks are at special risk for disease, because one infected person can spread the disease to many others. One study showed that the attack rate in household contacts was 500 times greater than that of the general population.
In some parts of the world, outbreaks of meningococcal disease occur regularly. This is true of a group of countries in sub-Saharan Africa, which is known as the "meningitis belt." Because travelers from this area visit Saudi Arabia during the Hajj, there have been outbreaks associated with the pilgrimage. Saudi Arabia now requires proof of meningococcal vaccination before admitting pilgrims. Prevention of similar outbreaks is possible; for example, many universities in the U.S. now require proof of meningococcal vaccination before the students can attend classes.