Abstract
Comprehensive understanding of the occurrence of pathogens in the aquatic environment is important for assessing possible biological health risks associated with water usage. The occurrence of bacterial pathogens in the Yodo and Kita Rivers, Kinki district, Japan, was investigated by using a DNA microarray targeting 1012 species/groups of bacterial pathogens infectious to human, animals, plants, fish, and shellfish. Eighty-seven pathogens were detected in 24 river water samples collected from two rivers, with more than half present in both rivers. The pathogen profile in the river waters varied primarily seasonally. Effluent from wastewater treatment plants, a well-known possible pathogen source, did not significantly affect the occurrence of bacterial pathogens in the monitored basins. Moreover, some of the detected pathogens, particularly non-fecal ones, did not positively correlate with the total coliform count, a conventional hygienic indicator. Therefore, the conventional hygienic indicator for fecal contamination is inadequate for comprehensive determination of the health risks associated with contamination of river water by bacterial pathogens.
