Occurrence and correlations between coliphages and anthropogenic viruses in the Massachusetts Bay using enrichment and ICC-nPCR

Abstract

We evaluated a two-step enrichment procedure to detect coliphages and an integrated cell culture-nested polymerase chain reaction (ICC-nPCR) to detect human astrovirus, enteroviruses, rotavirus and adenovirus type 40 and 41 in marine water samples collected by the Massachusetts Water Resource Authority (MWRA). MWRA has been monitoring its receiving waters for coliphages, anthropogenic viruses and indicator bacteria in order to evaluate the impact of Boston's Deer Island Sewage Treatment Plant discharge. Coliphages and enteric viruses were originally assayed using single agar overlay and most probable number cell culture (MPN) methods, respectively. Reanalysis of these samples for enteric viruses by ICC-nPCR demonstrated that 46% were positive for at least one virus compared with 23% with the MPN method. Use of the enrichment method showed a 47% increase in the detection of male specific and somatic coliphages compared with the single agar overlay method. Correlations between the presence of coliphages, enteric viruses and indicator bacteria were based on proximity to the treatment plant discharge, seasonal variations and site levels. The presence of enteric viruses was significantly correlated to coliphages but not to indicator bacteria. Preliminary comparative results demonstrate that effective and efficient monitoring of anthropogenic contamination can be achieved using these more sensitive and specific techniques.

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

“…In contrast, other studies have shown some correlation between human viruses and F-specific phages [23,123,126,140,141] and between human viruses and somatic coliphages in surface waters [104,140,142], between enteroviruses and somatic coliphages in sludge [82], and between human viruses and both somatic and F-specific phages in surface water [78]. Thus, even if the results far from indicate a clear correlation between indicator coliphage densities and human viruses in water, there is evidence that somatic and F-specific coliphages are more strongly associated with pathogenic viruses than the traditional bacterial indicators and even a particular pathogenic virus.…”

Waterborne Viruses and F-Specific Coliphages in Mixed-Use Watersheds: Microbial Associations, Host Specificities, and Affinities with Environmental/Land Use Factors

“…In the absence of significant fecal pollution inputs, the levels of F-specific coliphage may be well below the limit of detection. In such cases, perhaps an enrichment method for the detection of F-specific coliphages would provide more valuable information than direct enumeration (87). When Ballester et al retested archived seawater sample concentrates prepared from large volumes (Ͼ100 liters of water) for the presence of coliphages, the rate of detection increased from 8% to 58% using a two-step enrichment method (87).…”

“…In such cases, perhaps an enrichment method for the detection of F-specific coliphages would provide more valuable information than direct enumeration (87). When Ballester et al retested archived seawater sample concentrates prepared from large volumes (Ͼ100 liters of water) for the presence of coliphages, the rate of detection increased from 8% to 58% using a two-step enrichment method (87). However, with respect to sampling and laboratory management, processing larger volumes of water can be logistically cumbersome and would preclude, potentially, the identification of viral contamination in surface waters captured via the smaller-volume approaches defined in the current study, where over 1,150 samples from 24 surface water sampling sites were processed and analyzed.…”

Diversity of Somatic Coliphages in Coastal Regions with Different Levels of Anthropogenic Activity in São Paulo State, Brazil

“…Some authors have suggested the use of an enrichment method because of a significant correlation between somatic coliphages, total enteric viruses, and adenoviruses (11). Others proposed the use of one bacterial indicator and somatic coliphages, which could be more informative than two bacterial indicators (22,29), and the observation of somatic coliphage replication must not be argued as a limitation (27).…”

“…Marine viruses were first described by Spencer (43), though they were largely ignored for 3 decades because of the relatively low abundances inferred on the basis of culturebased assays (12). However, more recently, it has been recognized that viruses are extremely abundant in aquatic environments (11,17,40,46,47). The viruses may exceed the concentration of bacteria by up to 100 times, with their total numbers estimated to be 10 31 in the biosphere (12).…”