Molecular characterization of antimicrobial resistance organisms from drinking water and wastewater in a metropolitan city

BackgroundAntimicrobial resistant (AMR) organisms in environment may harm people. This study assessed the phenotypic and genotypic characteristics of AMR organisms from drinking and wastewater. Materials and methodsThis cross-sectional study conducted randomly on 30 samples (15 drinking water samples from household places; 15 sewage lifts stations) and collected aseptically, filtered, inoculated and isolated from culture plates, identified biochemically of pathogenic bacteria, and disc diffusion tested for antibiotic susceptibility. The primers of the targeted antimicrobial resistance genes were used for molecular amplification. ResultsTwenty-five bacteria were isolated from 30 drinking and wastewater samples. Pseudomonas spp. (36%), Enterobacter spp. (28%), Escherichia coli (20%), Citrobacter spp.(4%), Acinetobacter spp (4%) and Klebsiella oxytoca (4%) were isolated. Most of the isolates exhibited resistance to multiple groups of antibiotics, with meropenem, imipenem, gentamicin, ciprofloxacin, and amikacin showing the highest sensitivity against the isolates. Multiplex PCR confirmed the presence of two ESBL genes (blaSHV and blaCTX-M-15) and five carbapenemase genes (blaIMP, blaVIM, blaKPC, blaOXA1, blaNDM1) in resistant bacteria and blaCTX-M-15 (53.3%) followed by blaKPC (46.7%) genes were the most prevalent from drinking and wastewater samples respectively. According to WHOs sanitary inspection risk score classification, 60% of drinking water samples scored 4 out of 11, categorizing them as intermediate risk based on hazard score. ConclusionsThis study addresses antimicrobial resistance in the environment, emphasizing public health implications; advocating for improved environmental regulations to mitigate AMR organism discharge through wastewater and drinking water. The significance of the studyThe study attempted to determine the pattern of antimicrobial resistance of microorganisms using phenotypic and genotypic methods by polymerase chain reaction (PCR), targeting particular genes with specific sequence of primers. As in Bangladesh very few studies for antimicrobial resistance organisms from drinking water and wastewater around household and hospital environments in Dhaka city, yet finished to change public health perspectives, and inform respective authorities for making decision. Thus the research contributes to generating some evidence-based information about the reservoir of antimicrobial resistance in environment.