Amoebas in drinking water: a double threat
Analysis reveals widespread, hidden contamination by the sometimes lethal parasites
Amoebas — blob-shaped microbes linked to several deadly diseases — contaminate drinking-water systems around the world, according to a new analysis. The study finds that amoebas are appearing often enough in water supplies and even in treated tap water to be considered a potential health risk.
A number of these microorganisms can directly trigger disease, from a blinding corneal infection to a rapidly lethal brain inflammation. But many amoebas possess an equally sinister if less well-recognized alter ego: As Trojan horses, they can carry around harmful bacteria, allowing many types to not only multiply inside amoeba cells but also evade disinfection agents at water-treatment facilities.
A new analysis finds evidence of widespread contamination of water supplies with amoebas, such as the three Acanthamoeba cells shown here. Each contains many bacteria (some shown, red arrows), which can be toxic to humans. The light circle is a cyst, an amoeba resting inside a heavily protective shell.
Credit: F. Marciano-Cabral/Va. Commonwealth Univ. Sch. of Med.
Naegleria fowleri amoebas, like these, can glom onto nerve endings in the nose of an exposed individual and motor along them into the brain. There they can trigger encephalitis, a nerve infection that is quickly lethal. Feeding cups on their surface are where they take in bacteria from the environment or bits of tissue while living within a human host. Credit: F. Marciano-Cabral/Va. Commonwealth Univ. Sch. of Med.