Salmonella enterica serovar typhimurium and escherichia coli survival in estuarine bank sediments

Mahbubul H. Siddiqee, Rebekah Henry, Rebecca Coulthard, Christelle Schang, Richard Williamson, Rhys Coleman, Graham Rooney, Ana Deletic, David McCarthy

Research output: Contribution to journalArticleResearchpeer-review

2 Citations (Scopus)

Abstract

Estuarine bank sediments have the potential to support the survival and growth of fecal indicator organisms, including Escherichia coli. However, survival of fecal pathogens in estuarine sediments is not well researched and therefore remains a significant knowledge gap regarding public health risks in estuaries. In this study, simultaneous survival of Escherichia coli and a fecal pathogen, Salmonella enterica serovar Typhimurium, was studied for 21 days in estuarine bank sediment microcosms. Observed growth patterns for both organisms were comparable under four simulated scenarios; for continuous-desiccation, extended-desiccation, periodic-inundation, and continuous-inundation systems, logarithmic decay coefficients were 1.54/day, 1.51/day, 0.14/day, and 0.20/day, respectively, for E. coli, and 1.72/day, 1.64/day, 0.21/day, and 0.24/day for S. Typhimurium. Re-wetting of continuous-desiccated systems resulted in potential re-growth, suggesting survival under moisture-limited conditions. Key findings from this study include: (i) Bank sediments can potentially support human pathogens (S. Typhimurium), (ii) inundation levels influence the survival of fecal bacteria in estuarine bank sediments, and (iii) comparable survival rates of S. Typhimurium and E. coli implies the latter could be a reliable fecal indicator in urban estuaries. The results from this study will help select suitable monitoring and management strategies for safer recreational activities in urban estuaries.

Original languageEnglish
Article number2597
Number of pages13
JournalInternational Journal of Environmental Research and Public Health
Volume15
Issue number11
DOIs
Publication statusPublished - 21 Nov 2018

Keywords

  • Fecal indicator
  • Fecal pathogen
  • QMRA
  • Recreational risks
  • Waterborne pathogens

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