The flagellate is pear-shaped and biflagellate: this means that it has two flagella. In tissues, it appears they phagocytize (consume by enclosing and then digesting prey) red blood cells and destroy tissue by releasing cytolytic substances. In their free-living state, trophozoites feed on bacteria. The pseudopods form at different points along the cell, thus allowing the trophozoite to change directions. They travel by pseudopodia, which means that they extend parts of their body's cell membrane (the pseudopods) and then fill them with protoplasm to force locomotion. The trophozoites are characterized by a nucleus and a surrounding halo. This reproductive stage of the protozoan organism, which transforms near 25 ☌ (77 ☏) and grows best around 42 ☌ (106.7 ☏), proliferates by binary fission. The trophozoite attaches to olfactory epithelium, where it follows the olfactory cell axon through the cribriform plate (in the nasal cavity) to the brain. The trophozoite is the feeding, dividing, and infective stage for humans. fowleri has been found to encyst at temperatures below 10 ☌ (50 ☏). When conditions improve, the amoeba can escape through the pore, or ostiole, seen in the middle of the cyst. Factors that induce cyst formation include a lack of food, overcrowding, desiccation, accumulation of waste products, and cold temperatures. Trophozoites encyst due to unfavorable conditions. A cyst is a life-capsule resistant to adverse environmental-conditions. It is smooth, having a single-layered wall with a single nucleus. It is spherical and about 7–15 µm in diameter. The cyst form is the storage-state of this amoeba. The flagellate form can exist in the cerebrospinal fluid. It does not form a cyst in human tissue, where only the amoeboid trophozoite stage exists. fowleri occurs in three forms – as a cyst, a trophozoite (ameboid), and a biflagellate. The amoeba was identified in the 1960s in Australia but appears to have evolved in the United States. As the water temperature rises, its numbers increase. It is found in warm and hot freshwater ponds, lakes and rivers, and in the very warm water of hot springs. Naegleria fowleri is a thermophilic, free-living amoeba. īiotic phases: cyst, trophozoite, flagellate The naegleriasis infection has been documented in Australia in 1965, Czechoslovakia in 1962 to 1965, the United States in 2003, 2011, 2013, 2020, and 2021, and Pakistan in 2008. It can be seen in either an amoeboid or temporary flagellate stage. This microorganism is typically found in bodies of warm freshwater, such as ponds, lakes, rivers, hot springs, warm water discharge from industrial or power plants, geothermal well water, poorly maintained or minimally chlorinated (under 0.5 mg/m 3 residual) swimming pools, water heaters, soil, and pipes connected to tap water. It is a free-living, bacteria-eating microorganism that can be pathogenic, causing an extremely rare, sudden, severe and usually fatal brain infection called naegleriasis or primary amoebic meningoencephalitis (PAM). Naegleria fowleri, colloquially known as a ' brain-eating amoeba', is a species of the genus Naegleria, belonging to the phylum Percolozoa, which is technically not classified as true amoeba, but a shapeshifting amoeboflagellate excavate.

Ameba come cerebro