Free-living amoebae have been detected in a large number of man-made water systems, including
drinking water distribution systems. Some of these amoebae can harbor amoebae-resisting bacteria,
and thus potentially act as reservoirs and vehicles for a number of pathogens. The objectives of this
study were to: quantify the free-living amoebae present at different steps of drinking water production
and distribution; assess their potential association with Legionella spp.; and, identify possible control
strategies. Sampling campaigns were conducted in Europe on a series of drinking water treatment
plants supplied by different surface waters and applying different treatment technologies. The results
of this study confirm the presence of free-living amoebae in surface waters used for drinking water
production. Although surface water treatment chains significantly reduce their numbers, they do not
eliminate them totally. Moreover, when encysted, these microorganisms are highly resistant to
disinfectants. Consequently, control strategies in drinking water production should be principally
based on physical removal processes such as clarification and granular or membrane filtration.
Biofilms and sediments constitute ideal niches where they can feed on bacteria but also where they
can occasionally become infected by amoebae-resisting bacteria. Consequently, control strategies in
drinking water production and distribution should also include good management of sludge from
clarifiers, of filter backwash, and biofilm and sediment control in distribution systems. Includes references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 750 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 11/01/2008 |
