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Clinical Information

Meningococcal Disease: Technical & Clinical Information

Clinical Features

Fever, headache and stiff neck in meningococcal meningitis cases, and sepsis and rash in meningococcemia.

Etiologic Agent

Multiple serogroups of Neisseria meningitidis. Serogroups B, C, and Y cause the majority of disease in the United States. Serogroup W causes a small portion of disease, and serogroup A causes disease in developing countries and the meningitis belt of sub-Saharan Africa.

Burden of disease

Fewer than 1000 cases annually in the United States. Higher rates of disease occur in other countries. The largest burden is in sub-Saharan Africa, where epidemics during the dry season can cause disease in up to 2% of a population, resulting in thousands of cases and deaths during large epidemics.


10%-15% of cases are fatal. Of patients who recover 11%-19% have permanent hearing loss, mental retardation, loss of limbs, or other serious sequelae.


N. meningitidis colonizes mucosal surfaces of nasopharynx and is transmitted through direct contact with large droplet respiratory secretions from the patients or asymptomatic carriers. Humans are the only host. Asymptomatic nasopharyngeal carriers who are not a close contact of a patient with meningococcal disease do not require prophylaxis.

Risk Groups

Risk groups include household contacts of case patients, military recruits, first-year college students who live in residence halls, microbiologists who work with isolates of N. meningitidis, persons traveling to a country where meningococcal disease is epidemic or highly endemic, and patients without spleens or with terminal complement component deficiencies.  Infants less than one year of age and adolescents ages 16 through 21 years have higher rates of disease than other age groups, but cases occur in all age groups including the elderly.


Meningococcal disease is a reportable condition in all states. The state and local health department will conduct an investigation to ensure all close contacts are provided prophylaxis. See more about meningococcal disease surveillance.

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