Sagar M. Goyal

Quantitative Assessment of the Adsorptive Behavior of Viruses to Soils

To evaluate the potential for groundwater contamination by viruses, it is essential to understand the processes controlling virus adsorption to soil. Recent laboratory studies have indicated that the degree of viral adsorption is highly type and strain dependent. The purpose of this study was to statistically reexamine earlier data by grouping studied variables into a number of broad categories. The results indicated that different types and strains of viruses can be grouped by their ability to be similarly affected by certain soil characteristics. Viruses could be grouped into two general categories. For group I, the most important factors affecting adsorption were pH, organic matter, and exchangeable iron content of the soil. No studied soil characteristic was found to be significantly associated with adsorption of group I1 viruses. The implication is that adsorption-elution of group I viruses is more sensitive to certain soil characteristics than that of group 11. Certain types of coliphages were found to be better models for some types of enteroviruses than others.

Relationship of viruses and indicator bacteria in water and wastewater of Israel

Abstract Different aquatic resources of Israel were monitored to obtain information on the occurrence of enteroviruses and their relationship to the bacteriological indicators of water quality. A total of 155 samples of groundwater, surface water, potable water and swimming pool water were examined, of which 45 (29.0%) yielded virus. Echovirus type 7 was the most predominant, followed by poliovirus 1, echovirus 6 and coxsackieviruses B2, B5 and B6. Virus was isolated on several occasions when the water in question met current bacteriological standards. Viruses were isolated from water samples with no detectable fecal or total coliform bacteria. No significant statistical correlation could be determined between the occurrence of bacterial indicators and the presence of viruses. This study raises serious doubts about the validity of the indicator bacteria concept to predict the virological quality of water, particularly in countries with a high incidence of enteric viral disease.

Viradel method for detection of rota virus from seawater

This report describes the use of a virus adsorption-elution (Viradel) technique for the concentration and detection of rotavirus from seawater. Simian rotavirus SA-11 was used as a model virus because it can be readily propagated and plaqued in vitro. The virus adsorbed optimally to fiberglass epoxy filters when seawater was adjusted to pH 3.5 and aluminum chloride added to a concentration of 1.0 mM. Adsorbed virus was eluted with 6% beef extract at pH 10.5 and was further concentrated to a smaller volume by a modification of the organic flocculation method. Using this method, in conjunction with an indirect immunofluorescence test, rotavirus was detected in sewage-contaminated seawater.

Transferable drug resistance in bacteria of coastal canal water and sediment

Abstract This study was undertaken to determine the comparative incidence of drug-resistant coliforms and salmonellae in the water and bottom sediments of six coastal canal communities which are used heavily for recreational activities. Of a total of 423 coliforms, 300 fecal coliforms and 100 salmonella isolates examined, 74.9% coliforms, 61.3% fecal coliforms and 71.0% salmonellae were resistant to one or more of the 12 antibiotics tested. Multiple resistance occurred in 48.9% coliforms, 32.7% fecal coliforms and 68.0% salmonella strains. A total of 178 coliforms, 137 fecal coliforms and 51 salmonella isolates were tested for the presence of resistance transfer factors, and 53.9%, 53.3% and 56.9% isolates, respectively, were capable of transferring their resistance patterns to Escherichia coli and/or Salmonella choleraesuis recipient strains. A significantly higher number of drug-resistant bacteria carrying R-factors (R + ) was found to occur in sediment than in surface water.

Type and strain dependence of enterovirus adsorption to activated sludge, soils and estuarine sediments

Abstract The degree of enterovirus adsorption to surfaces was found to be both type- and strain-dependent.

Occurrence of enteroviruses in community swimming pools.

Municipal swimming pools and wading pools were examined for the presence of human enteric viruses using a portable virus concentrator at the site to concentrate viruses from 100-gallon to 500-gallon samples. Ten of 14 samples contained viruses; three of these were positive for virus in the presence of residual free chlorine. Enteroviruses were isolated from two pools which exceeded the 0.4 ppm free residual chlorine standard. This study appears to be supportive of recent evidence that indicates a higher incidence of enterovirus infection among bathers. All seven wading pool samples contained virus. Coxsackieviruses B3 and B4, poliovirus 1, and echovirus 7 were isolated. Total coliform bacteria were not adequate indicators of the presence of virus, as six of the samples were positive for virus but negative for coliforms. Total plate counts appeared to provide a better indication of the sanitary quality of the pool water, but viruses could still be detected in samples that met currently recommended bacterial levels. It is possible that swimming and wading pools may serve as a means of transmission of enteroviral disease, especially in children, during summer months.

Characteristics of humic acid and organic compounds concentrated from tapwater using the aquella virus concentrator

Abstract Humic acid and other organic compounds present in eluates from filters used to process large volumes of treated tapwater using the Aquella virus concentrator were found to share certain properties. Both humic acid and the other organic compounds in the filter eluates adsorbed to membrane filters at low pH, were eluted from membrane filters at high pH, interfered with virus adsorption to membrane filters, formed flocs at low pH, and were removed by anion-exchange resins.

Prevalence of Enteroviruses in Ground Water of Israel

Few studies have been performed on the occurrence of enterovirus contamination of ground water. In this study, 99 ground-water samples were examined for the presence of enteroviruses, total bacteria, fecal coliforms, and fecal streptococci by standard methods. Enteroviruses were isolated from 20% of the samples. Viruses were isolated from 12 samples which contained no detectable fecal organisms per 100 ml. No statistical correlation between presence of virus and bacteriological indicators could be determined. The widespread failure of current bacteriological standards to indicate the presence of potentially pathogenic enteroviruses in ground water is an area of concern that requires more study.

Distribution of viral and bacterial pathogens in a coastal canal community

Abstract Significant concentrations of human enteric viruses and bacteria were found to be present in the water and sediment of a coastal canal community into which secondarily treated sewage was being discharged.

A simple method for concentration of enteroviruses and rotaviruses from cell culture harvests using membrane filters

Organic compounds in cell culture harvests known as membrane-coating components (MCC) prevent virus adsorption to membrane filters. Blending cell culture harvests with fluorocarbon removed the MCC and permitted adsorption of virus in acidified harvests to epoxy-fiberglass filters. Subsequent elution with high pH buffer resulted in recovery of greater than 90% of the virus with concentrations of up to 100-fold.