Evaluating the Role of Wastewaters as Reservoirs of Antibiotic-Resistant ESKAPEE Bacteria Using Phenotypic and Molecular Methods

Syeda Samar Mustafa; Rida Batool; Muhammad Kamran; Hasnain Javed; Nazia Jamil

doi:10.2147/IDR.S368886

Evaluating the Role of Wastewaters as Reservoirs of Antibiotic-Resistant ESKAPEE Bacteria Using Phenotypic and Molecular Methods

Infect Drug Resist. 2022 Sep 28:15:5715-5728. doi: 10.2147/IDR.S368886. eCollection 2022.

Authors

Syeda Samar Mustafa¹, Rida Batool¹, Muhammad Kamran², Hasnain Javed³, Nazia Jamil¹

Affiliations

¹ Institute of Microbiology and Molecular Genetics, Quaid e Azam Campus, University of the Punjab 54590, Lahore, Pakistan.
² Queensland Alliance for Agriculture and Food Innovation Centre for Animal Science, University of Queensland, Brisbane, Queensland, 4072, Australia.
³ Provincial Public Health Reference Lab, Punjab AIDS Control Program, Lahore, Pakistan.

Abstract

Introduction: Wastewaters carrying thousands of human specimens from the community and representing the diversity of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) directly from the community mirror the extent of AR spread in the community and environment. This study aimed to investigate the occurrence and distribution of antibiotic-resistant ESKAPEE bacteria in the community versus clinical settings through monitoring nonclinical and clinical wastewaters.

Methodology: Seven wastewater samples were collected from different environmental sources. Isolates were obtained on general and selective media, biochemically characterized and antimicrobial-susceptibility tests performed by disk diffusion against 13 antibiotics according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines using MastDisc disk cartridges, and 16S rRNA metagenomic analysis was performed for two water samples.

Results: Of 43 isolates, all representatives of the ESKAPEE group were recovered from clinical wastewaters, but Gram-positive cocci were not obtained from nonclinical wastewaters. The most predominant isolate was Pseudomonas aeruginosa (n=15; 33%), followed by Escherichia coli (n=9; 20%). Complete (100%) resistance to eleven of the tested antibiotics was observed, with only a few isolates being susceptible to clarithromycin, amikacin, and gentamicin. The lowest (79%) resistance rate was observed for linezolid. The multiple antibiotic resistance (MAR) index was calculated, and the resistance phenotype was independent of the wastewater source, indicated by x ² (P=0.766). Metagenomic analysis replicated the results, as Pseudomonas spp., Acinetobacter spp., and Escherichia spp. were found to be predominant. The integrase gene (IntI1) was also amplified in Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa.

Conclusion: Wastewaters are significant carriers of drug-resistant ESKAPEE bacteria and play an important role in their dissemination. This study endorses the periodic surveillance of water systems to evaluate the presence and burden of antibiotic-resistant pathogens.

Keywords: ESKAPEE; IntI1; metagenome; resistance profiling; wastewater.

Grants and funding

No formal funding or grant was provided for this study.