Species identification and antibiotic susceptibility of municipal solid waste pathogens from sewage soil and water in the capital region in A.P.

AbstractThis study investigates the prevalence, identification and antibioticsusceptibility of bacterial pathogens isolated from sewage-contaminated soiland water samples collected across four municipal regions in South Tenali,North Tenali, Vijayawada and Guntur, Andhra Pradesh, India. A total of 20environmental samples were analyzed for their response to the antibioticAmpicillin (10 μg) using the standard disk diffusion method. Resultsrevealed a wide variation in resistance profiles among isolates, with zone ofinhibition (ZOI) values ranging from as low as 0.1 mm (indicating highresistance) to as high as 54.5 mm (indicating high susceptibility). Notably,isolates from South Tenali-1, Vijayawada-3 and North Tenali-4 showedstrong sensitivity, whereas samples from Vijayawada-2, Vijayawada-4 andNorth Tenali-5 exhibited significant resistance, suggesting the presence ofmultidrug-resistant (MDR) strains. Sewage water samples showed higherrates of antibiotic resistance than soil samples, highlighting the role ofuntreated wastewater in the dissemination of resistance genes. Molecularidentification of bacterial isolates using 16S rRNA gene sequencing revealeddominant strains belonging to Shigella flexneri, Shigella sonnei, Escherichiafergusonii, Shigella dysenteriae and Escherichia coli, with sequencesimilarities ranging from 97% to 98.4%. Furthermore, the detection of thesepathogens in sewage-irrigated agricultural soils raises critical concerns abouttheir potential impacts on crop productivity, food safety and the transfer ofantibiotic resistance genes into agricultural ecosystems.