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Medical Term:

Neisseria meningitidis


a bacterial species found in the nasopharynx of humans but not in other animals; the causative agent of meningococcal meningitis and meningicoccemia; virulent organisms are strongly gram negative and occur singly or in pairs; in the latter case the cocci are elongated and are arranged with long axes parallel and facing sides kidney shaped; groups characterized by serologically specific capsular polysaccharides are designated by capital letters (the main serogroups being A, B, C, and D).

Synonym(s): meningococcus, Weichselbaum coccus

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