Antimicrobial Profiling of Resistant Genes in Bacteria Isolated from Drinking Water Sources in Bonny Island, Rivers State, Nigeria

Abstract

The global health crisis of antimicrobial resistance (AMR) necessitates a profound understanding of its dynamics, particularly in environmental reservoirs such as drinking water sources. The aim of the study was to identify the presence and variety of antibiotic-resistant genes (ARGs) within bacteria isolated from drinking water sources in Bonny Island, Rivers State, Nigeria – an area characterized by unique ecological and human-induced factors. Eighty water samples were collected from drinking water distribution systems within Bonny Island for a period of six month. Bacteria isolated from drinking water samples within Bonny Island underwent antimicrobial profiling, including susceptibility tests against a range of clinically relevant antibiotics. Molecular techniques were employed to identify the isolated bacteria and characterize specific ARGs, illuminating the genetic basis of resistance in the isolated bacteria. The bacterial isolates displayed varying resistance patterns, with the highest resistance observed against cefuroxime (59.6%), cefotaxime (48.9%), ceftazidime (44.7%), ceftriaxone (36.3%), chloramphenicol, and Augmentin (29.8%), while resistance to cotrimoxazole and gentamicin was lower (12.8%). Among the bacterial isolates, the tet gene, conferring resistance to tetracycline antibiotics, was present in 46.7% of cases, while 100% exhibited the oxa gene and 93.3% possessed the aac(6’)-ib gene. Preliminary findings revealed a diverse array of bacteria with varying resistance profiles, including both common and emerging pathogens. The identified ARGs covered genes providing resistance to a broad spectrum of antibiotics, including beta-lactams, fluoroquinolones, and tetracyclines. These results underscore the potential risks associated with the spread of ARGs in drinking water sources and their potential transfer to pathogenic bacteria.