Naegleria

A genus of free-living soil, water, and sewage ameba (order Schizopyrenida, family Vahlkampfiidae) one species of which, N. fowleri, has been implicated as the causative agent of the rapidly fatal primary amebic meningoencephalitis. Infection has been traced to swimming pools (including indoor chlorinated pools); entry is by the nasal mucosa, from which the amebae reach the meninges and brain through the cribriform plate and olfactory nerves. Other soil amebae that have been implicated, although of far less epidemiologic significance, include the genera Acanthamoeba and Hartmanella, the latter being a suspected but unproved causative agent.

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Nae·gle·ria nā-'glir-ē-ə n a genus of diphasic ameboid protozoans that are characterized by a predominate ameboid stage and a minute flagellate stage with two flagella, that occur esp. in stagnant water and are often coprozoic, and that include one (N. fowleri) causing meningoencephalitis in humans

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n.

a genus of amoeba that normally live in damp soil or mud. Naegleria species can, however, live as parasites in humans and are believed to have caused some rare, but fatal, infections of the brain.

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Nae·gle·ria (na-glērґe-ə) a genus of free-living protozoa (order Schizopyrenida, subclass Gymnamoebia) found in fresh water, soil, and sewage; they have both an ameboid and a flagellate stage in their life cycles, with two flagella present in the latter stage. Infection is usually acquired by swimming in contaminated water. Certain species, especially N. fowґleri, are capable of facultative parasitism; some strains are highly pathogenic and may cause fatal primary amebic meningoencephalitis.

Naegleria fowleri trophozoites in brain tissue.