Antibiogram and beta-lactamase genes among cefotaxime resistant E. coli from wastewater treatment plant

Abstract

Background: The World Health Organization (WHO) recently classified Enterobacteriaceae resistance to thirdgeneration cephalosporin into the group of pathogens with critical criteria for future research. Methods: A study to assess the antibiogram and beta-lactamase genes among the cefotaxime resistant E. coli (CREc) from a South African wastewater treatment plant (WWTP) was conducted using standard phenotypic and molecular biology characterization methods. Results: Approximate total E. coli (TEc) concentration (log 10 CFU/mL) ranged between 5.7 and 6.8 among which cefotaxime resistant E. coli were between 1.8 and 4.8 (log 10 CFU/mL) for cefotaxime antibiotic concentration of 4 and 8 mg/L in the influent samples. Effluent samples, heavily influenced by the chlorination had only 0.3 log 10 CFU/ mL of TEc. Fifty-one cefotaxime resistant isolates were selected out of an overall of 75 isolates, and subjected to a new round of testing, with a follow up of 36 and 48 isolates for both colistin and gentamicin, respectively as guided by initial results. Selected CREc exhibited resistance to amoxicillin-clavulanic acid (35.3%; n = 51), colistin sulphate (76.5%; n = 36), ciprofloxacin (47.1%; n = 51), gentamicin (87.5%; n = 48) and intermediate-resistance to meropenem (11.8%; n = 51). Extended spectrum-beta-lactamase genes detected, viz.: bla CTX-M (52.6%; n = 38) and bla TEM (84.2%; n = 38) and concurrent bla CTX-M + bla TEM (36.8%; n = 38), but no bla SHV was detected. Carbapenem resistance genes, blaKPC-2 (15.8%; n = 38), blaOXA-1 (57.9%; n = 38), blaNDM-1 (15.8%; n = 38) were also detected. Approximately, 10.5-36.8% (n = 38) co-occurrence of two or more beta-lactamase genes was detected in some isolates. Out of the selected number (n = 30), 7(23.3%) were enterotoxigenic E. coli (ETEC), 14 (46.7%) were Enteroaggregative E. coli (EAEC), but no enteropathogenic E. coli (EPEC) was detected. Conclusion: Resistance to cefotaxime and the presence of a wide range of beta-lactamase genes exposed the potential risks associated with these pathogens via occupational and domestic exposure during the reuse of treated wastewater.

Global colistin use: a review of the emergence of resistant Enterobacterales and the impact on their genetic basis

“…In addition to animals and humans, two reports from South Africa and Tunisia demonstrated colistin resistance among cefotaxime-resistant E. coli (76.5%) as well as ESBL-producing Enterobacterales (10.8%) that were mcr -negative, isolated from waste water (Adegoke et al . 2020 ; Hassen et al . 2020 )…”

Distribution of Antibiotic-Resistant Enterobacteriaceae Pathogens in Potable Spring Water of Eastern Indian Himalayas: Emphasis on Virulence Gene and Antibiotic Resistance Genes in Escherichia coli

“…Water quality assessment is the need of this hour to predict and minimize the future risks of water-borne diseases especially in rural areas of developing countries. Commensal bacteria living in the gastrointestinal tract of humans and animals mostly from Enterobacteriaceae family are used as a microbiological indicator of water quality and fecal contamination (Stange et al, 2016;Adegoke et al, 2020). There are several common fecal coliform genera such as Escherichia, Klebsiella, Citrobacter, Enterobacter, Morganella, and Hafnia (Stange et al, 2016).…”

New Insight on Antibiotic Resistance and Virulence of Escherichia coli from Municipal and Animal Wastewater

“…Adegoke et al [ 29 ] analysed E. coli isolates from municipal wastewater from South African WWTP and found in influent a large number of pathogenic cefotaxime-resistant E. coli that carried ESBL (blaCTX-M and blaTEM) and carbapenem resistance genes (blaKPC-2, blaOXA-1, and blaNDM-1) individually and concurrently. It was found out that they originated from hospitals.…”