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Bathing Water Quality and Human Health

 

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Amoeba

published on 01/08/2008
 
 

Origine

Amoeba are micro-organisms present in all components of the environment. They thrive in humid areas, particularly warm freshwaters where the temperature is between 25°C and 40°C. Only a few of the free amoeba found in the environment are hazardous to man. One is the species Naegleria fowleri.
The warm waters discharged from industrial facilities, in particular electrical power plants, can foster the development of amoeba. The discharge and environments affected are all subject to special monitoring.
Bathing can entail health risks when the local environment is assumed to contain high amoeba concentrations and when the bather inhales water droplets. The risk results from the concentration of amoeba pathogens in the water. This is particularly true of children, who are a favourite target for amoeba.
 
More information:
The term free amoeba refers to amoeba that do not require an intermediate host to develop. Free amoeba can be found in vegetative immediately pathogenic form, or in cystic form, which enable them to withstand outdoor conditions that are less conducive to their development. The cystic forms found in the environment can become pathogenic to man, and should therefore not be neglected.

Health Impacts

Contamination occurs through inhalation: the amoeba enter the brain through the nasal mucous glands and develop there. The disease caused by Naegleria Fowleri (Nf) is an amibiase that leads to brain inflammation (meningoencephalitis). The most common symptoms are headache, fainting, convulsions, drowsiness and, sometimes, abnormal anxiety. The disease is very rare but may be deadly when a diagnosis is lacking.
Since 1967, a total of only 196 cases of meningoencephalitis have been identified across the world, not all due to bathing in contaminated environments. As of today, no cases have been reported in France. This is likely due to the fact that the concentrations found in the environment were low.