Use of bituminous coal as an alternative technique for field concentration of waterborne viruses

An Appraisal of Bacteriophage Isolation Techniques from Environment

Researchers have recently renewed interest in bacteriophages. Being valuable models for the study of eukaryotic viruses, and more importantly, natural killers of bacteria, bacteriophages are being tapped for their potential role in multiple applications. Bacteriophages are also being increasingly sought for bacteriophage therapy due to rising antimicrobial resistance among pathogens. Reports show that there is an increasing trend in therapeutic application of natural bacteriophages, genetically engineered bacteriophages, and bacteriophage-encoded products as antimicrobial agents. In view of these applications, the isolation and characterization of bacteriophages from the environment has caught attention. In this review, various methods for isolation of bacteriophages from environmental sources like water, soil, and air are comprehensively described. The review also draws attention towards a handful on-field bacteriophage isolation techniques and the need for their further rapid development.

Chapter 9 The Detection of Waterborne Viruses

Viruses in water are usually present in concentrations too low for detection by direct analysis. Virological investigation of water samples is always a multi-stage process involving concentration of viruses present followed by an appropriate detection procedure. There are several approaches to detection of viruses. Part or all of the concentrate may be inoculated into cell cultures to detect infectious cytopathogenic virus, and if this is done in a quantitative fashion the virus can be enumerated, the count being reported as plaque-forming units, the tissue culture infectious dose, or most probable number units. The virus may be isolated and identified from the cell cultures. Viruses that multiply without producing an identifiable cytopathic effect in culture may sometimes be detected by immunoperoxidase or immunofluorescence staining. The concentrate may also be analyzed by molecular biological procedures (usually polymerase chain reaction (PCR) or real-time-PCR). The problem then is that such techniques do not usually detect the infectious virus, and novel approaches have been made recently to meet this challenge.

Detecting Viruses in Water

Various and divergent approaches that have been used to concentrate and assay viruses from tap water and environmental freshwaters are summarized and briefly explained. The basic principles behind the different methodologies and descriptions of the most recent developments are emphasized. Comparisons help demonstrate the relative sensitivities of different concentration and assay techniques.