Antibiotic resistance patterns of diverse Escherichia coli phylogenetic groups isolated from the Al-Hillah river in Babylon province, Iraq

Abstract

Surface water contamination remains a major worldwide public health concern and may contribute to the dissemination of antibiotic-resistant bacteria. The Al-Hillah River in the city of Babylon Province, Iraq, diverts flows from the Euphrates River. Because of its importance in irrigation and population density, it faces several forced and unforced changes due to anthropogenic activities. To evaluate water quality, water samples were collected from three sites with different anthropogenic pressures along the Al-Hillah River. These samples were subjected to bacteriological analyses, i.e., total coliforms, Escherichia coli, and faecal enterococci. The phylogenetic groups of the E. coli isolates (n = 61) were typed by rapid PCR-based analyses. Representatives of each isolate were tested phenotypically for resistance to six classes of antibiotics and characterized according to their phylogenetic groups. The results demonstrated the highest resistance levels were to β-lactam antibiotics, followed by fosfomycin and aminoglycosides. Escherichia coli isolates belonging to phylogenetic groups A and B2 were the most common and were characterized by a higher prevalence of antibiotic resistance. This study is important for understanding the current conditions of the Al-Hillah River, as the data reveal a high prevalence of multiresistance among E. coli isolates circulating at the three sampling sites.