Methods for Virus Sampling and Analysis of Ground Water

The consumption of contaminated ground water is responsible for almost half of the reported waterbome disease outbreaks each year in the United States. Enteric viruses continue to be a significant cause of such waterbome disease. Methods for virus detection in ground water are needed to assess the safety of ground-water supplies. Viruses in ground water may originate from septic tanks, leaking sewer lines, domestic and sludge landfills, land disposal of sewage effluent, leaking sewage ponds, etc. Because of the potential health significance of low numbers of viruses in water, it is necessary to sample large volumes of water (40 to 1000 L). The method most commonly used is the microporous filter adsorption/elution technique. This involves passing water through a filter to which the viruses adsorb and subsequently eluting (deadsorbing) the viruses off the filter using a 1 to 2-L suspension of 3% beef extract. This eluate is further reconcentrated to a volume of 20 to 30 mL before assay. Currently, this concentrate is then assayed by animal cell culture. Newer techniques for virus detection should dramatically reduce the time and cost of virus detection in ground water.