The case of an unidentified man who died due to an infection caused by an amoeba known as a “brain eater”, called Naegleria Fowleri, generated fear in many people, mainly due to the way in which the contagion occurs, through nasal hygiene.
Naegleria Fowleri is a microorganism found in land and air, but more commonly in fresh water, generally at higher temperatures, around 46° C, normally present in warm water lakes or rivers, thermal waters, tap water, heaters , and more rarely in untreated swimming pools and water wells.
Naegleria Fowleri infections are considered rare, and precisely for this reason, there are not enough studies to better understand it and identify effective medications, which is why it has high mortality rates, over 97%, of the 111 cases already registered in the USA alone. one survived the infection.
Generally, infection occurs through the nose, whether through religious practices, cleaning the area or swimming, which causes the amoeba to reach the brain through the olfactory nerve in a bone plate in the skull, causing an infection called PAM – Primary Amoebic Meningoencephalitis.
Naegleria Fowleri enters the body in the form of a trophozoite – an adult stage of microorganisms used for food – this state gives it structures capable of allowing the ingestion of tissues from the human body, which allows it to “eat” the brain tissue of the infected person .
The amoeba has adhesins on its surface, components that facilitate its adhesion to the body’s cells. By accessing nerve cells, Naegleria Fowleri is able to absorb them through a structure known as “food cups”, in addition, it expresses a pore-forming cytolytic protein that depolarizes the cell’s membrane potential, causing it damage.
It is also capable of releasing hydrolytic enzymes, such as neuraminidases, sphingosine and choline, which damage the cell’s membrane, made up mainly of lipids, causing loss of functions in nervous tissues.
The organism presents a strong immunological response, which associated with the effects of the amoeba results in serious damage to the Central Nervous System, which generates symptoms that can range from headaches, vomiting, loss of balance and disorientation, similar to those caused by meningitis, to more serious problems such as seizures, stiff neck, hallucinations and coma.
Typically, the diagnosis of PAM is made in people who have symptoms that affect the Central Nervous System and a history of contact with contaminated water. Imaging tests, such as computed tomography and magnetic resonance imaging, can also be used, in addition to the use of brain puncture to obtain cerebrospinal fluid samples for testing, but more than 75% of diagnoses are only made after the patient’s death.
However, if water contaminated with Naegleria Fowleri is ingested, there is no risk of infection as the stomach acid kills the microorganism, therefore, the main prevention is to avoid contact of the water with the nose, when necessary, opt for distilled water or sterile, use nose clips when swimming, the average age of affected individuals is 12 years, so it is important to pay attention to children playing in rivers and lakes
Currently, although in cases of the disease some medications such as azithromycin, fluconazole and rifampicin can be administered intravenously or orally, their effects are limited, which can be even more difficult as in most cases death occurs within a eighteen days after the onset of symptoms.
