Prevalence of human enteric viruses in coastal canal communities

Several residential canal systems into which wastewater that had received secondary treatment was being discharged were studied to assess the nature, extent, and sanitary significance of human enteric viruses in these waters and to determine the relationship, if any, between the presence of viruses, indicator bacteria, and other physicochemical characteristics of the water in these canals. Significant concentrations of enteric viruses were found in recreational coastal waters which met acceptable bacteriological standards for contact recreational activity. No significant statistical relationship was demonstrated between virus concentration and the presumptive total coliforms in sediments. No correlation was found between virus number and various physicochemical characteristics of water. On several occasions pathogenic human enteric viruses were isolated from water which contained no detectable fecal coliforms, indicating that conventional bacteriological indicators may not be suitable indicators for determination of a viral disease hazard.