Occurrence and densities of bacteriophages proposed as indicators and bacterial indicators in river waters from Europe and South America

Abstract

Aims: To evaluate the feasibility of bacteriophages as a complementary tool for water quality assessment in surface waters from different parts of the globe. Methods and Results: Faecal coliform bacteria, enterococci, spores of sulphite-reducing clostridia, somatic coliphages, F-specific RNA bacteriophages and bacteriophages infecting Bacteroides fragilis were determined by standardized methods in raw sewage and in 392 samples of river water from 22 sampling sites in 10 rivers in Argentina, Colombia, France and Spain, which represent very different climatic and socio-economic conditions. The results showed that the indicators studied maintained the same relative densities in the raw sewage from the different areas. Classifying the river water samples according to the content of faecal coliform bacteria, it can be observed that the relative densities of the different bacterial indicators and bacteriophages changed according to the concentration of faecal coliform bacteria. There was a relative increase in the densities of all groups of bacteriophages and sulphite-reducing clostridia with respect to faecal coliforms and enterococci in the samples with low counts of faecal coliform bacteria. Conclusions: The numbers of bacterial indicators and bacteriophages were similar in the different geographical areas studied. Once released in rivers, the persistence of the different micro-organisms differed significantly. Bacteriophages and spores of sulphite-reducing clostridia persisted longer than faecal coliforms and enterococci. Significance and Impact of the Study: Bacteriophages in river water samples provide additional information to that provided by bacteria about the fate of faecal micro-organisms in river water. The easy, fast and cheap methods for phage determination are feasible both in industrialized and developing countries.

The effect of antimicrobials on verocytotoxin bacteriophage transduction under bovine rumen fluid and broth conditions

“…The decrease in free phages from their peak values was unexpected as viral pathogens are generally considered to survive better that their cellular hosts, a phenomenon that has been demonstrated with Vtx phages (Muniesa et al, 1999;Lucena et al, 2003;Skraber et al, 2004). Moreover, the peak phage concentrations were similar to those previously recorded in human, cattle and poultry waste water and in bovine faeces (Imamovic et al, 2010;Rooks et al, 2012).…”

Coliphages as Model Organisms in the Characterization and Management of Water Resources

“…With respect to community septic tanks, somatic and F-specific coliphages were detected in all samples tested, with values ranging from 10 6 to 10 7 PFU per 100 mL and 10 5 to 10 6 PFU per 100 mL, respectively [94].…”

“…Thus, somatic coliphages are detected in raw municipal wastewater throughout the world in 100% of the samples tested and values range from 5ˆ10 6 -10 7 PFUs per 100 mL, with those of F-specific phages ranging from 10 4 to 10 6 PFUs per 100 mL [20,48,71,94,95]. With respect to community septic tanks, somatic and F-specific coliphages were detected in all samples tested, with values ranging from 10 6 to 10 7 PFU per 100 mL and 10 5 to 10 6 PFU per 100 mL, respectively [94].…”

Bacteriophage Removal Efficiency of In-line Coagulation with Ceramic Membrane Filtration

“…In addition, its survival characteristics in aquatic environments are similar to those of human enteric viruses. The average concentrations of F-specific RNA bacteriophage that commonly found in wastewater are ranging from 1 to 5 log10 plaque-forming units (PFU)/ml [8][9][10] and 1 to 3 log10 PFU/ml in river water [9,[11][12] The one of the most important factor for human survival is access to the high quality of potable water [13]. Membrane filtration is the promising technology which has been used extensively all over the world for potable water production and wastewater treatment.…”