Concentration and detection of rotavirus in water samples using polymerase chain reaction during a gastroenteritis epidemic outbreak in Madras city

Detection of enteropathogens by PCR

The widespread problem of contaminated water by enteric microorganisms necessitates the need to develop a rapid protocol to detect pathogens in water bodies. Usual methods like plating, biochemical tests and use of DNA probes are time consuming which is a limiting factor especially in epidemic situations. Moreover, some cells can exist in a virulent viable but non-culturable state making detection very difficult by plating method. This paper describes a rapid method to detect the enteropathogens,E.coli, Salmonella andVibrio and enteric viruses from water samples by Polymerase Chain Reaction.E.coli was specially chosen as it is an indicator of fecal contamination. The sensitivity ofE.coli detection was improved to 10 cells to keep in tune with the WHO guidelines. The presence ofE.coli would also indicate the probable presence of other pathogens.

Use of bituminous coal for concentration of enteroviruses from sewage and effluent

A method has been developed for concentration of enteroviruses from untreated and treated domestic wastewater using bituminous coal bed as a virus adsorbent. A bed made from 1.5 g of 120 mesh coal powder was used for concentrating enteroviruses from 100 ml of clarified sewage at different pH values with and without addition of AlCl3. To enhance the adsorption of viruses, requisite quantities of aluminium chloride were added so that a final concentration of 0.0005 M could be achieved. At pH 3.0 maximum adsorption (82.8%) of poliovirus type 1 from artificially contaminated clarified sewage was observed without addition of AlCl3. However, at pH 5.0 maximum virus adsorption of 98.7% was achieved after addition of aluminium chloride. An average recovery of 86.9% of adsorbed viruses at pH 5.0 was achieved from coal bed with 3% flocculating beef extract at pH 9.5. This method for concentration of enteroviruses incorporating use of coal was compared with that of Millipore membrane filter method applied to raw sewage and clarified sewage. The results obtained from the methodology using coal as adsorbent was subjected to Student's "t" test and it was observed that its efficiency is confirmed for recovery of enteroviruses from raw and nonclarified sewage. These results are also comparable with that obtained with MF method. The results presented in this paper are indicative of the potential of this method for both treated and raw sewage.

Environmental biotechnology in India: prospects and case studies

The emergence and acceptance of the concept of sustainable development warrants that the scope of environmental biotechnology be enlarged to address issues like environmental monitoring, restoration of environmental quality, resource/residue/waste-recovery/utilization/treatment, and substitution of the non-renewable resource base with renewable resources. This paper delineates the current and prospective applications in these sub-areas of environmental biotechnology, and documents case studies on environmental monitoring (enteric viruses), restoration of environmental quality (oil spill remediation), resource recovery (hydrocarbon recovery from oily sludges, biosurfactants from distillery spentwash, desulphurization of coal & sour gases), and substitution of non-renewable resources with renewables (conversion of lignocellulisics into value added chemicals).

A simple device for the concentration and detection of enterovirus, hepatitis E virus and rotavirus from water samples by reverse transcription-polymerase chain reaction

A simultaneous concentration of enteroviruses, hepatitis E virus, and rotavirus from drinking water samples through a filtration column filled with granular activated carbon (GAC) was achieved. Urea-arginine phosphate buffer (UAPB) as an eluent at pH 9.0 was used for effective desorption and elution of viruses from GAC. Further concentration of viruses with magnesium chloride enabled nucleic acid extraction, cDNA synthesis, amplification with a specific set of primers for enterovirus, hepatitis E virus and rotavirus. Polymerase chain reaction (PCR) products were then confirmed by Southern transfer and hybridization with the relevant probes. The efficacy of the protocol was established with 100 1 of water samples seeded with poliovirus-1, providing 74% recovery in granular activated carbon based UAPB-RT-PCR. The GAC-based method for concentration of viruses from water samples was preferred, despite its somewhat lower efficacy compared to 80% in membrane filter based UAPB-RT-PCR protocol, due to the specific requirements of short-time and savings in cost of analyses. The protocol was used for the detection of waterborne viruses from 24 drinking water sources in urban areas of New Delhi. Direct isolation of viruses from water samples revealed that the 4 samples were positive for enteroviruses, two for hepatitis E virus, and 10 samples for rotavirus. One sample was positive for both hepatitis E virus and rotavirus, and another for all the 3 types of viruses.