Survey of human virus occurrence in wastewater-recharged groundwater on Long Island

245

Standard methods for the detection of enteroviruses in environmental samples involve the use of cell culture, which is expensive and time-consuming. The polymerase chain reaction (PCR) is an attractive method for the detection of enteroviruses in water because primary cell culture is not needed and the increased sensitivity of PCR allows detection of the low numbers of target DNAs and RNAs usually found in environmental samples. However, environmental samples often contain substances that inhibit PCR amplification of target DNA and RNA. Procedures that remove substances that interfere with the amplification process need to be developed if PCR is to be successfully applied to environmental samples. An RNA-PCR assay for the detection of enteroviruses in water was developed and used to test a variety of groundwater concentrates and humic acid solutions seeded with poliovirus type 1. The groundwater samples and humic acid solutions were treated with Sephadex G-50, Sephadex G-100, Sephadex G-200, Chelex-100 resin, and a mixed bed resin to remove PCR-inhibitory material from the samples. Sephadex G-100 in combination with Chelex-100 was found to be very effective in removing inhibitory factors for the detection of enteroviruses in groundwater concentrates by PCR. Viruses were detected in two of the groundwater concentrates by the RNA-PCR assay after treatment with Sephadex G-100 plus Chelex-100. This was confirmed by tissue culture, suggesting that the treatment protocol and, subsequently, the RNA-PCR assay are applicable for the detection of enteroviruses in environmental samples.

mentioning

confidence: 99%

Detection of enteroviruses in groundwater with the polymerase chain reaction

Abbaszadegan

Huber

Gerba

et al. 1993

245

“…Septic tanks discharge more than 800 billion gal (3.028 x 1012 liters) of wastewater to the subsurface every year and are the most frequently reported sources of groundwater contamination (21). Enteric viruses can survive in septic tanks (10; S. L. Stramer, Ph.D. dissertation, University of Wisconsin, Madison, 1984), and their progress from the septic tank to the soil absorption field and into the underlying groundwater has been monitored (10,23,24; Stramer, Ph.D. dissertation). Viruses can survive for prolonged periods in groundwater (27) and have remained infective in the environment long enough to cause several waterborne outbreaks of disease.…”

mentioning

confidence: 99%

Use of geostatistics to predict virus decay rates for determination of septic tank setback distances

Yates¹,

Yates²,

Warrick³

et al. 1986

Water samples were collected from 71 public drinking-water supply wells in the Tucson, Ariz., basin. Virus decay rates in the water samples were determined with MS-2 coliphage as a model virus. The correlations between the virus decay rates and the sample locations were shown by fitting a spherical model to the experimental semivariogram. Kriging, a geostatistical technique, was used to calculate virus decay rates at unsampled locations by using the known values at nearby wells. Based on the regional characteristics of groundwater flow and the kriged estimates of virus decay rates, a contour map of the area was constructed. The map shows the variation in separation distances that would have to be maintained between wells and sources of contamination to afford similar degrees of protection from viral contamination of the drinking water in wells throughout the basin.

“…Within the past few years, a number of investigators have documented the presence of human enteroviruses in sewage-recharged aquifers (13,14,20), including those designated as "sole source aquifers" (18). Although the public health significance of enteroviruses in groundwater remains debatable, it has been shown that 57% of all outbreaks of water-borne diseases are of suspected viral etiology (2).…”

Section: Discussionmentioning

confidence: 99%

Poliovirus retention in 75-cm soil cores after sewage and rainwater application

Landry¹,

Vaughn²,

Penello³

1980

Self Cite

The adsorption rate of a guanidine-resistant strain of poliovirus LSc 2ab was measured in Long Island soils with in situ field cores (10.1 by 75 cm). The test virus was chosen because it exhibited soil adsorption and elution characteristics of a number of non-polioviruses. After the inoculation of cores with seeded sewage effluent at a 1-cm/h infiltration rate, cores were extracted, fractionated, and analyzed for total plaque-forming units per each 5-cm fraction. The results showed that 77% of the viruses were adsorbed in the first 5 cm of soil. An additional 11% were found in the 5-to 10-cm fraction, and a total of 96% of the viruses were adsorbed by 25 cm. The remaining 4% were uniformly distributed over the next 50 cm of soil, with a minimum of 0.23% in each soil section. Few viruses (<0.22%) were observed in core filtrates. Analysis of the viral distribution pattern in seeded cores, after an application of a single rinse of either sewage effluent or rainwater, indicated that large-scale viral mobilization was absent. However, localized areas of viral movement were noted in both of the rinsed cores, with the rainwaterrinsed cores exhibiting more extensive resorbed at lower core depths. movement. All mobilized viruses were Disposing of treated sewage effluent via basin recharge appears to be a viable and prudent method for supplementing groundwater reservoirs. The successful implementation of such recharge practices demands a thorough knowledge of the behavior and movement of sewageborne human pathogens in the receiving soils and groundwater. The isolation of human enteric viruses from treated sewage effluents (17, 18), as well as from groundwaters beneath wastewater recharge basins (14, 17, 18, 20) indicates that a better understanding of virus-soil interactions during the recharge process is required. Knowledge gained from an evaluation of these basic interactions could improve recharge practices and minimize virus contamination of the aquifer. A recent review by Bitton et al. (1) indicated that many of the basic interactions which occur between viruses and soil particles have been established in soil cores or columns. These interactions seem to be regulated by: (i) the virus type (5); (ii) the composition and pH of the soil (5, 7); (iii) the conductivity of the applied wastewater (3, 11); and (iv) the rate and schedule of wastewater application (6, 11). Recently, Vaughn et al. (18) reported that the groundwaters at three recharge sites on Long Island were contaminated with human enteric viruses.