The gut microbiome of the healthy population in Kolkata, India, is a reservoir of antimicrobial resistance genes emphasizing the need of enforcing antimicrobial stewardship

De, R.; Kanungo, S.; Mukhopadhyay, A. K.; Dutta, S.

doi:10.1101/2023.07.17.549428

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bioRxiv · 10.1101/2023.07.17.549428

The gut microbiome of the healthy population in Kolkata, India, is a reservoir of antimicrobial resistance genes emphasizing the need of enforcing antimicrobial stewardship

De, R.·Kanungo, S.·Mukhopadhyay, A. K.·Dutta, S.

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Abstract

Antimicrobial resistance (AMR) alleviation warrants antimicrobial stewardship (AS) entailing indispensability of epidemiological surveillance. We undertook a small-scale surveillance in Kolkata to detect the presence of antimicrobial resistance genes (ARGs) in the healthy gut microbiome. We found that it was a reservoir of ARGs against common antibiotics. A targeted PCR and sequencing-based ARGs detection against tetracyclines, macrolides, trimethoprim, sulfamethoxazole, aminoglycosides, amphenicol and mobile genetic element (MGE) markers was deployed in twenty-five fecal samples. Relative abundance and frequency of ARGs was calculated. We detected markers against all these classes of antibiotics. 100% samples carried aminoglycoside resistance marker and int1U. A comparison with our previously published diarrheal resistome from the same spatial and temporal frame revealed that a higher diversity of ARGs were detected in the community and a higher rate of isolation of tetC, msrA, tmp and sul-2 was found. The presence of common markers in the two cohorts proves that the gut microbiome has been contaminated with ARGs and which are being disseminated among different ecosystems. This is an issue of discerning concern for public health. The study raises an alarming picture of the AMR crisis in low-middle and emergent economies. It emphasizes the strict enforcement of AS in the community.

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De, R., Kanungo, S., Mukhopadhyay, A. K., Dutta, S.. 2023-07-18. The gut microbiome of the healthy population in Kolkata, India, is a reservoir of antimicrobial resistance genes emphasizing the need of enforcing antimicrobial stewardship. https://doi.org/10.1101/2023.07.17.549428

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