Antimicrobial Susceptibility Profiles of Bacteria Isolated from The Ozama River in Santo Domingo, Dominican Republic

Bonnellly, R.; Cavalcante, A. L. Q.; del Rosario Zorrilla, C.; Calderon, V. V.; Duarte, A.; Barauna, R. A.; Juca Ramos, R. T.; Rodriguez, Y.; Rodriguez de Francisco, L. E.; Maroto, L. O.; Perdomo, O. P.; Franco, E. F.

doi:10.1101/2022.09.19.508624

bioRxiv · 10.1101/2022.09.19.508624

Antimicrobial Susceptibility Profiles of Bacteria Isolated from The Ozama River in Santo Domingo, Dominican Republic

Bonnellly, R.·Cavalcante, A. L. Q.·del Rosario Zorrilla, C.·Calderon, V. V.·Duarte, A.·Barauna, R. A.·Juca Ramos, R. T.·Rodriguez, Y.·Rodriguez de Francisco, L. E.·Maroto, L. O.·Perdomo, O. P.·Franco, E. F.

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Abstract

The dissemination of antimicrobial-resistant bacteria in environmental waters is an emerging concern in medical and industrial settings. In the present study, our research team analyzed superficial water samples from 3 different collection sites along the Ozama River, the most important river in the Dominican metropolitan area. Seventy-six isolates were obtained from culture media previously enriched with cefotaxime and imipenem and subsequently identified by MALDI-ToF. Our isolates spanned 12 genera of bacteria; over 30% were of clinical relevance, and 43% exhibited a phenotype classified as multi-drug resistance. The most frequent species identified as Stenotrophomonas maltophilia (n = 33), an emerging nosocomial pathogen. This study constitutes part of the initiative to understand the profiles of the perils of multi-drug resistance in metropolitan areas of the Dominican Republic: a nation with poor antibiotic use regulation. IMPORTANCENearly two billion people are sourcing their water from low-quality reservoirs world-wide. These reservoirs consist of contaminated waters with anthropogenic pollutants such as antibiotics, disinfectants, and other substances used to treat water in societies with scarce resources and unregulated industries. Furthermore, the exposure of these antibiotics to potable water reservoirs promotes the increase of clinically relevant bacteria with antibiotic-resistance capabilities, becoming a public health crisis. Therefore, treating patients with infectious diseases and providing prophylactic measures against infection-associated conditions (such as post-surgical recovery) has become progressively more difficult. Based on this evidence frame, it is of considerable importance to analyze the bacterial profiles of rivers that fall prey to anthropogenic contamination, as these investigations on antibiotic resistance will, of course, benefit the life of humans.

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Bonnellly, R., Cavalcante, A. L. Q., del Rosario Zorrilla, C., Calderon, V. V., Duarte, A., Barauna, R. A., Juca Ramos, R. T., Rodriguez, Y., Rodriguez de Francisco, L. E., Maroto, L. O., Perdomo, O. P., Franco, E. F.. 2022-09-22. Antimicrobial Susceptibility Profiles of Bacteria Isolated from The Ozama River in Santo Domingo, Dominican Republic. https://doi.org/10.1101/2022.09.19.508624

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