Unexpected Prevalence of eae-Positive Escherichia coli in the Animas River, Durango, Colorado

Abstract

Since 2014, biology students at Fort Lewis College have studied the water quality of the Animas River in Durango, Colorado. Environmental microbiology and molecular biology techniques have been employed to study Escherichia coli isolates from the river and to define characteristics of the bacteria related to public health. E. coli was found in the river, as well as in culverts and tributary creeks that drain into the river within the Durango city limits. Concentrations of E. coli in the river occasionally exceeded the US EPA guideline of 126 CFU per 100 mL for recreational water use. Many of the E. coli isolates were able to be grown at 45 °C, an indication of mammalian origin. Unexpectedly, 8% of the isolates contained the intimin (eae) gene, a virulence gene characteristic of two pathotypes of E. coli, the enterohemorrhagic and enteropathogenic E. coli. Several isolates tested were resistant to multiple antibiotics commonly used in animal and human medicine. Further study is warranted to determine the source of these bacteria entering the Animas River, and to further characterize the possible disease potential of multi-antibiotic resistant and virulence gene-containing isolates found in a semi-rural/urban setting.

Microbial Prevalence in Soil Water in the River Deltas of the World

“…Again a study on Colorado River basin delta represents that siltation of sandstones and fine grained clay substances constitute the rocky soil composition of this delta. The detritus growth on drainage river basin dominates calcite, quartz and subordinate dolomites including plagioclase, illite, kaolinite, zircon, magnetite, clinozoisite, leucoxene, chlorite and biotite [51][52][53][54].…”

Progress toward alleviating preventable waterborne diseases over the past 30 years

“…There were companies at the time working to develop arrays that could be used in environmental detection, including drinking water, but to my knowledge, they never reached the commercial level. PCR was beginning to revolutionize our ability to detect Escherichia coli and specific pathogens, something we used extensively for source tracking in the Ganges, Little Bighorn, and Animas Rivers (Hamner et al, 2007(Hamner et al, , 2014(Hamner et al, , 2020. At the same time, whole genome sequencing was becoming cheaper and simpler.…”