Comparative study on enteric pathogens and their relations with fecal indicator bacteria in urban surface waters
城市地表水中肠道病原微生物与粪便污染指示菌的关系研究

In this study, Salmonella typhi, Shigella sp. and Escherichia coli were selected as typical enteric pathogens in urban surface waters and characterized by the real-time PCR methods. The occurrences of pathogens were investigated in urban surface waters including source of drinking water supply, landscape water and urban river. Enteroviruses were detected in most of water samples with the concentration below 103 copy·L-1. The concentration of Escherichia coli was obviously different between the reserved waters and the waters receiving sewage. Salmonella typhi and Shigella sp. often appeared in the fecal contaminated waters. By statistical analysis, the concentrations of enteric pathogens in each water body all followed the log-normal distribution. There was no significant correlation between fecal indicator bacteria and enteroviruses. Nevertheless, fecal indicator bacteria can reflect the presence of typical enteric pathogens in urban surface waters to some extent. The positive rate of Salmonella typhi or Shigella sp. was high in the water samples where the concentration of total coliforms or fecal coliforms was above 104 CFU·L-1.