Antimicrobial Resistance and ARGs Detection in Treated Final Effluent from STPs: An Upcoming Challenge to the Environment

Aim: The present study analysed the presence of antimicrobial resistance organisms and genes in the final effluent from STPs of hospitals.

Study Area and Sampling: Samples for microbiological analysis were collected from two different hospitals in Trivandrum City and carried out further microbiological analysis.

Methodology: In this study, MDRB (Multi Drug Resiatant Bacteria) were detected from the hospital effluent samples collected from two hospitals. Antibiotic susceptibility analysis showed that the 90% screened organisms was resistant to different antibiotics -Tetracycline (30µg), Amikacin (30µg), Gentamycin (10µg), Ciprofloxacin (5µg), Colistin (10µg) and Amoxicillin (30µg)). Metagenomic surveillance of effluent helped to assess the efficacy of STPs, at the same time assessing the local clinical antibiotic resistance condition by detection of the presence of antimicrobial resistance towards antibiotics and their genes (ARGs) in the hospital effluent.

Results: In this study, a total of 3 antibiotic resistant bacterial strains obtained from hospital STP effluent were identified by16S rRNA sequence analysis. The sequences of E.coli, Klebsiella and Enterobacter were submitted in Genbank with accession number MT784125, OM978270 andMN437586 respectively.The final effluent from Hospital 1 showed100% resistance to Tetracycline and 86% resistance to Amoxicillin followed by sensitivity 28%, 22%, 18% and 10% respectively to Ciprofloxacin, Gentamycin, Amikacin and Colistin. The bacterial strains isolated from final effluent of Hospital 2 showed highest resistance to Amikacin and Colistin which is 100% and 86% and 82% resistance to Gentamycin and Ciprofloxacin. The gene primers used for the respective genes above have been amplified in the sample with a higher efficiency of 16 SrRNA, ermB and ampC primers showing a lower Cq value. Thus, these three genes were detected in the samples at high amount which showed the prominent use of the consecutive antibiotics in the clinical field