DAILY VARIABILITY OF NATURALLY OCCURRING WATERBORNE PATHOGENS IN A STREAM SYSTEM

Surface waters are an important source for recreation and irrigation but can be reservoirs of pathogens. There has been considerable work on surface water contamination with enteric pathogens, but we know less about the frequency and distribution of naturally occurring pathogens, and their contribution to microbial communities in stream systems. The objective of this work was to identify and evaluate population dynamics of presumptive Aeromonas and Vibrio and microbial composition in a freshwater stream over a daily time series. Water samples were collected from May through December 2024, filtered onto membranes and used for total community DNA extraction and culturing on TCBS agar. Two well-isolated colonies were picked for each sample and streaked for purification. Isolates were screened as presumptive Vibrio and Aeromonas using genus specific qPCR assays. Most isolates were identified as presumptive Aeromonas but genome sequencing suggests this includes other opportunistic pathogens as well. Presumptive Aeromonas and Vibrio copies/mL were determined from total community DNA extracts, resulting in a wide range of copies per mL over the study period. Concentrations were highest in the summer months, suggesting a seasonal variability in distribution. Additional work will evaluate the broader microbial community composition and explore species specific distribution using whole genome sequencing and targeted PCR. This work will address the scale of naturally occurring bacterial pathogens in a freshwater system and their ecological impact including risks to humans and animals.

Presentation Preference: Poster

Primary Presenter: Elisabeth Drake, University of Georgia (ebd36516@uga.edu)

Authors:

Elisabeth Drake, University of Georgia  (ebd36516@uga.edu)

Esther Palmer, University of Georgia  (esther.palmer@uga.edu)

Dawson Deal, University of Georgia  (dawson.deal@uga.edu)

Nikki Shariat, University of Georgia  (Nikki.Shariat@uga.edu)

Keri Lydon, University of Georgia  (keri.lydon@uga.edu)

Erin Lipp, University of Georgia  (elipp@uga.edu)