Technically not an actual amoeba, Naegleria fowleri is an amoeboid eukaryotic protist that is usually found in freshwater environments. Moreover, this organism has an affinity for warm water, and it has been found in water as hot as 45°C. Hence, thermally polluted water bodies, such as industrial runoffs and powerplants, provide favorable breeding grounds. Therefore, it is advisable to seek suitable control measures of water pollution to prevent the risk of infections.
Naegleria cannot survive in environments with high salinity. It cannot live in chlorinated water as well. This organism is colloquially known the brain-eating amoeba because it can enter through the nose and start feeding on the brain. During harsh conditions, the protist reverts to a cyst form; it is dormant, but resilient to many environmental factors, which would otherwise kill the organism. Harsh conditions include a shortage of nutrients, desiccation, cold temperatures, and overcrowding. When favorable conditions return, the amoeba can revert to its active form – called the trophozoite. The protists do not exist in the cyst form when inside a human body. The trophozoite form is the active form where feeding and dividing occurs. Moreover, this is the stage where the organism can infect humans.
Out in its natural environment, the organism typically consumes bacteria; it does this by enveloping the bacteria and releasing lytic enzymes capable of dissolving cellular contents. However, once it enters the brain, there are no other sources of nutrition, hence, it starts feasting on brain cells by releasing the lytic enzymes to destroy the cellular membrane.
The body’s immune system responds to the infection, which often results in inflammation of the brain. Unfortunately, the skull is a sturdy structure and it cannot expand to accommodate the swelling. Forebrain parts, such as the Cerebrum gets damaged due to the increased pressure, thereby compromising many important functions of the body.
As stated before, the organism enters the body when the individual is exposed to warm, freshwater environments. After initial exposure, it takes an average of 5 days for symptoms to appear. Symptoms include severe headache and fever. Other symptoms include stiff neck, lack of attention, loss of balance and hallucinations. Death can occur in 2-3 weeks after the onset of the symptoms. A person infected with this disease has a mortality rate of 99{e8320b3a48b868d914fa32d2d6dd13b99d3fcdd8bc3f2724f7c5e8c2702076aa}. The disease is non-communicable, meaning that it cannot be passed on to another person.
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