Extended-spectrum β-lactamase-producing Escherichia coli in wastewaters and refugee camp in Lebanon

Aim: To evaluate the effects of population influx of refugees on the prevalence of extended-spectrum beta-lactamase-producing Escherichia coli in wastewater networks in Lebanon. Materials & methods: Pulsed-field gel electrophoresis, multilocus sequence typing and antibiotic resistance genes typing were performed. Results: 53.1% of isolates recovered from Al-Qaa refugee camp were positive for the tested resistant determinants compared with 49.1% from river effluents. All isolates carried aac(6)-1b and/or aac(3)-II; none carried armA, rmtB, ant(4')-Iia, aph(3')-Ia or carbapenemases. CTX-M-15, TEM-1, OXA-1, CMY-2 and SHV-12 were detected. Single and/or double substitutions were detected in GyrA and ParC. Phylogenetic group B2 and ST6470 were the most prevalent. Pulsed-field gel electrophoresis revealed 19 XbaI patterns and 17 pulsotypes. Conclusion: The introduction of novel resistance patterns into the wastewater network requires effective control.