The endemic disease manifests itself in small clusters or sporadically. Cerebrospinal meningitis or meningococcal meningitis caused by Neisseria meningitidis is the only disease that occurs in epidemic form. In developing countries, most often epidemic disease is indistinguishable from endemic disease because of the lack of adequate laboratory resources to clearly diagnose the disease. Thus meningococcal meningitis is grouped with the other endemic forms of bacterial meningitis. It is spread efficiently when the respiratory droplets of the infected person are spread to other individuals.
Humans presenting with meningococcal meningitis are the predominant carriers of the organisms.
The infection begins when the bacteria colonize the nasopharynx. The organisms have pilli on their surface to assist in adhering to nasopharyngeal mucosal receptors. The usual signs and symptoms of meningococcal meningitis.