Freshwater environment as a reservoir of extended-spectrum beta-lactamase-producing Enterobacteriaceae

Surface water receives large quantities of wastes from human and animal sources, thus providing an ideal setting for the accumulation, development, and dissemination of antibiotic resistant bacteria, including extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae. The rapid spread of ESBL-producing Enterobacteriaceae, particularly Escherichia coli and Klebsiella pneumoniae, is a growing threat to public health, and there have been increasing reports on the prevalence and abundance of ESBL-producing Enterobacteriaceae in aquatic environments all over the globe. The objective of this review is to understand the extent of ESBL-producing Enterobacteriaceae contamination in aquatic environments and to enhance our knowledge on the role of the freshwater environment as a reservoir and transmission routes for these bacteria. In this review, we present the prevalence and distribution of ESBL-producing Enterobacteriaceae and their ESBL genes in the freshwater environment, potential sources of these bacteria in the aquatic environment, as well as their potential drivers in the environment, including anthropogenic and environmental factors.