CTX-M-Producing Bacteria Isolated from a Highly Polluted River System in Portugal

Marta Tacão, José Laço, Pedro Teixeira and Isabel Henriques ()
Additional contact information
Marta Tacão: CESAM and Biology Department, University of Aveiro, 3810-193 Aveiro, Portugal
José Laço: Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal
Pedro Teixeira: CESAM and Biology Department, University of Aveiro, 3810-193 Aveiro, Portugal
Isabel Henriques: Department of Life Sciences and CFE, University of Coimbra, 3000-456 Coimbra, Portugal

IJERPH, 2022, vol. 19, issue 19, 1-17

Abstract: Enterobacteriaceae resistant to third-generation cephalosporins are a great concern for public health, as these are first-line drugs to treat infections. The production of carbapenemases and extended spectrum beta-lactamases (ESBLs) and/or the overexpression of AmpC β-lactamases are the main mechanisms of resistance to these antibiotics. Among the ESBLs, CTX-M β-lactamases are the most prevalent worldwide. Our aims were to determine the prevalence of cefotaxime-resistant Enterobacteriaceae along a heavily polluted river and characterize bla CTX-M carriers. River water was collected in 11 sites along the main course and tributaries, in two sampling moments. Water quality was evaluated and a collection of cefotaxime-resistant isolates was obtained. bla CTX-M carriers were characterized regarding phylogenetic affiliation, clonality, antibiotic susceptibility, gene diversity, and context. Water presented very low quality in all sites. From 147 cefotaxime-resistant isolates, 46% carried bla CTX-M and were affiliated with Escherichia , Klebsiella , Enterobacter , and Citrobacter . Molecular typing revealed clonal isolates in different sites and over the two years, suggesting survival of the strains in the river or continuous pollution inputs from the same sources. Eight variants of bla CTX-M were found, with bla CTX-M-15 being the most prevalent (52.5%). Sites with a lower water quality showed the highest resistance rates and prevalence of bla CTX-M , suggesting that river water may embody human health risks.

Keywords: bla CTX-M; river pollution; antibiotic resistance; ?-lactamases; Enterobacteriaceae; pig farms (search for similar items in EconPapers)
JEL-codes: I I1 I3 Q Q5 (search for similar items in EconPapers)
Date: 2022
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1660-4601/19/19/11858/pdf (application/pdf)
https://www.mdpi.com/1660-4601/19/19/11858/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jijerp:v:19:y:2022:i:19:p:11858-:d:920009

Access Statistics for this article

IJERPH is currently edited by Ms. Jenna Liu

More articles in IJERPH from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().