scholarly journals Cooccurrence of Five Pathogenic Legionella spp. and Two Free-Living Amoebae Species in a Complete Drinking Water System and Cooling Towers

Pathogens ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1407
Author(s):  
Alshae Logan-Jackson ◽  
Joan B. Rose

Pathogenic Legionella species grow optimally inside free-living amoebae to concentrations that increase risks to those who are exposed. The aim of this study was to screen a complete drinking water system and cooling towers for the occurrence of Acanthamoeba spp. and Naegleria fowleri and their cooccurrence with Legionella pneumophila, Legionella anisa, Legionella micdadei, Legionella bozemanii, and Legionella longbeachae. A total of 42 large-volume water samples, including 12 from the reservoir (water source), 24 from two buildings (influents to the buildings and exposure sites (taps)), and six cooling towers were collected and analyzed using droplet digital PCR (ddPCR). N. fowleri cooccurred with L. micdadei in 76 (32/42) of the water samples. In the building water system, the concentrations of N. fowleri and L. micdadei ranged from 1.5 to 1.6 Log10 gene copies (GC)/100 mL, but the concentrations of species increased in the cooling towers. The data obtained in this study illustrate the ecology of pathogenic Legionella species in taps and cooling towers. Investigating Legionella’s ecology in drinking and industrial waters will hopefully lead to better control of these pathogenic species in drinking water supply systems and cooling towers.

2017 ◽  
Vol 18 (5) ◽  
pp. 1664-1673 ◽  
Author(s):  
Fuad Ameen ◽  
Alhanouf Albejad ◽  
Rukaia Gashgari ◽  
S. Murialdo ◽  
A. Al-Sabri

Abstract The occurrence of fungi in drinking water systems has received increased attention over recent decades and fungi are now generally accepted as drinking water system contaminants. However, fungal contamination of bottled water has received little attention. Forty unopened bottled water samples, of different trademarks, were collected from various localities in Jeddah city, Saudi Arabia and analyzed for fungal contamination: (1) immediately after opening the bottles; and (2) after closing and storing them for 180 and 365 days. The fungal species were identified under a compound microscope followed by molecular sequencing. At least one fungal species were found in 58% of the bottles. In total, 18 fungal species belonging to 11 fungal genera were identified. Rhizopus nigricans and seven different species of Aspergillus were found to frequently contaminate the bottled water samples. Penicillium sp. were found in one sample. The 180 days storage of opened and reclosed bottles did not substantially affect the abundance of fungi or the species found. Some of the fungi identified may be pathogenic and the contamination of fungi in bottled water should be considered during the processing of water.


Author(s):  
A.V. Abramkin ◽  
R.S. Rakhmanov

Surface water resources of Mordovia Republic characterized by an inconstant output during a year, therefore, underground artesian waters use for household and drinking water supply. In 2009–2015 the quality of drinking water samples taken in 22 districts of Mordovia was unfavorable according to content of fluorine (taken in 13 districts and city of Saransk), iron (taken in 11 districts and city of Saransk), strontium (1 district), iodine was absent in all water samples. The main contaminant was fluorides, their level was up to 1,5–5,2 MAC. The development and scientific substantiation of hygienic actions on group and individual prevention of exposure to elevated concentrations of fluorine as well as iodine deficiency in human body are required.


Medicina ◽  
2019 ◽  
Vol 55 (8) ◽  
pp. 492 ◽  
Author(s):  
Valciņa ◽  
Pūle ◽  
Mališevs ◽  
Trofimova ◽  
Makarova ◽  
...  

Background and Objectives: Legionella is one of the most important water-related pathogens. Inside the water supply systems and the biofilms, Legionella interact with other bacteria and free-living amoeba (FLA). Several amoebas may serve as hosts for bacteria in aquatic systems. This study aimed to investigate the co-occurrence of Legionella spp. and FLA in drinking water supply systems. Materials and Methods: A total of 268 water samples were collected from apartment buildings, hotels, and public buildings. Detection of Legionella spp. was performed in accordance with ISO 11731:2017 standard. Three different polymerase chain reaction (PCR) protocols were used to identify FLA. Results: Occurrence of Legionella varied from an average of 12.5% in cold water samples with the most frequent occurrence observed in hot water, in areas receiving untreated groundwater, where 54.0% of the samples were Legionella positive. The occurrence of FLA was significantly higher. On average, 77.2% of samples contained at least one genus of FLA and, depending on the type of sample, the occurrence of FLA could reach 95%. In the samples collected during the study, Legionella was always isolated along with FLA, no samples containing Legionella in the absence of FLA were observed. Conclusions: The data obtained in our study can help to focus on the extensive distribution, close interaction, and long-term persistence of Legionella and FLA. Lack of Legionella risk management plans and control procedures may promote further spread of Legionella in water supply systems. In addition, the high incidence of Legionella-related FLA suggests that traditional monitoring methods may not be sufficient for Legionella control.


2015 ◽  
Vol 77 ◽  
pp. 119-132 ◽  
Author(s):  
Sarah Rodríguez-Martínez ◽  
Yehonatan Sharaby ◽  
Marina Pecellín ◽  
Ingrid Brettar ◽  
Manfred Höfle ◽  
...  

2013 ◽  
Vol 14 (4) ◽  
pp. 393-398

The occurrence of trihalomethanes (THMs) was studied in the drinking water samples from urban water supply network of Karachi city that served more than 18 million people. Drinking water samples were collected from 58 locations in summer (May-August) and winter (November-February) seasons. The major constituent of THMs detected was chloroform in winter (92.34%) and summer (93.07%), while the other THMs determined at lower concentrations. Summer and winter concentrations of total THMs at places exceed the levels regulated by UEPA (80 μg l-1) and WHO (100 μg l-1). GIS linked temporal variability in two seasons showed significantly higher median concentration (2.5%-23.06%) of THMs compared to winter.


Water ◽  
2018 ◽  
Vol 10 (5) ◽  
pp. 582 ◽  
Author(s):  
Ljiljana Zlatanović ◽  
Aleksandra Knezev ◽  
Jan van der Hoek ◽  
Jan Vreeburg

2015 ◽  
Vol 156 ◽  
pp. 972-979 ◽  
Author(s):  
Qihua Wu ◽  
Honglan Shi ◽  
Yinfa Ma ◽  
Craig Adams ◽  
Hua Jiang ◽  
...  

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