Phylogenetic group distribution and antibiotic resistance of <i>Escherichia coli</i> isolates in aquatic environments of a highly populated area

Abstract

&lt;abstract&gt;&lt;sec&gt; &lt;title&gt;Background&lt;/title&gt; &lt;p&gt;Extended-spectrum beta-lactamase (ESBL)-producing &lt;italic&gt;Enterobacteriaceae&lt;/italic&gt; including &lt;italic&gt;Escherichia coli&lt;/italic&gt; (&lt;italic&gt;E. coli&lt;/italic&gt;), are recognized as a global public health threat due to their multidrug-resistant (MDR) phenotypes and their rapid dissemination in aquatic environments. Nevertheless, studies investigating the prevalence and antimicrobial resistance (AMR) profile of ESBL-producing &lt;italic&gt;E. coli&lt;/italic&gt; in Lebanese surface water are limited.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Objective&lt;/title&gt; &lt;p&gt;This study aimed to assess the physicochemical properties and microbial contamination load and to determine the distribution of AMR patterns of ESBL-producing &lt;italic&gt;E. coli&lt;/italic&gt; in surface water samples from different sites in the North Governorate of Lebanon.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Methods&lt;/title&gt; &lt;p&gt;Water samples were collected from 25 major sites in North Lebanon. These samples were analyzed for the presence of total coliforms, &lt;italic&gt;E. coli&lt;/italic&gt;, and fecal enterococci. Phenotypic and genetic characterizations were then performed for &lt;italic&gt;E. coli&lt;/italic&gt; isolates to determine their resistance patterns and phylogenetic groups.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Results&lt;/title&gt; &lt;p&gt;Fifty-six samples out of 100 samples were positive for ESBL-producing &lt;italic&gt;E. coli&lt;/italic&gt;, mostly harboring bla&lt;sub&gt;CTX-M&lt;/sub&gt; (40/56, 71%) including bla&lt;sub&gt;CTX-M-15&lt;/sub&gt; (33/40, 82%), bla&lt;sub&gt;TEM&lt;/sub&gt; gene (36/56, 64%), bla&lt;sub&gt;SHV&lt;/sub&gt; (20/56, 36%), and bla&lt;sub&gt;OXA&lt;/sub&gt; (16/56, 29%) including bla&lt;sub&gt;OXA-48&lt;/sub&gt; gene (11/16, 69%). Most ESBL-producing &lt;italic&gt;E. coli&lt;/italic&gt; isolates belonged to the extra-intestinal pathogenic phylogroup B2 (40/56, 71.4%) while 10/56 (17.9%) belonged to the commensal phylogroup A.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Conclusion&lt;/title&gt; &lt;p&gt;Our results highlight the need to implement effective water monitoring strategies to control transmission of ESBL-producing &lt;italic&gt;E. coli&lt;/italic&gt; in surface water and thus reduce the burden on human and animal health.&lt;/p&gt; &lt;/sec&gt;&lt;/abstract&gt;