Presence of antibiotic resistance genes in raw source water of a drinking water treatment plant in a rural community of USA

Very few studies have been reported on the presence of antibiotic resistance genes in the raw source water of rural communities in the USA. Therefore this study was conducted to study the presence of few specific antibiotic resistance genes, which imparts resistance to commonly used antibiotics in a rural drinking water plant in Louisiana, USA. Samples were taken from raw intake water, the treated water in holding tank at the water treatment facility, and an offsite consumer source serviced by the distribution line. Water quality analysis uncovered increase in organic carbon in distributed water. No live bacteria were found in the treated or distributed water, but bacterial DNA in the form of 16s rRNA was consistently found. Isolates of antibiotic resistant E. coli, Enterobacter cloacae, Pseudomonas aerugenosa, and Klebsiella pneumonia were found in the raw intake water. Antibiotic resistance genes, tetA and sul1 were observed in the raw intake showing the presence of antibiotic resistance genes (ARG) and antibiotic resistant bacteria (ARB) in the raw intake water. However, no ARGs or ARB were found in the treated and distributed water.