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Makhtar Camara

Publications and source records attributed to Makhtar Camara.

2 recordsLinked to original sources
PubMed2026

Frequency and characteristics of extended-spectrum beta-lactamase-producing Escherichia coli in wastewater in Dakar, Senegal.

OBJECTIVE: This study aimed to investigate the occurrence, antimicrobial resistance profiles, and genetic characteristics of extended-spectrum beta-lactamase (ESBL)-producing E. coli in wastewater collected in Dakar, Senegal. RESULTS DESCRIPTION: All samples (n = 48) carried ESBL-producing isolates. The concentrations of ESBL-producing E. coli ranged from 1.4 × 10⁴ to 3.3 × 10⁵ CFU/100 mL, whereas the ratio of ESBL-producing E. coli among the total E. coli population varied between 0.2% and 16.3%. All the 107 isolated ESBL-producing E. coli isolates were multidrug resistant (MDR), with 100% resistance to beta-lactams (ampicillin, cefalotin, cefotaxime, ceftazidime, cefepime, aztreonam) and high resistance rates to non-beta-lactam antibiotics, including ciprofloxacin (77.6%). No resistance was observed to imipenem. CTX-M-type genes were present in all isolates, with blaCTX-M-1 group (89.7%) and blaCTX-M-8 group (88.8%) being the most prevalent. The blaCTX-M-15 variant, a subgroup of blaCTX-M- group1, was detected in 96.9% of blaCTX-M-1 positive isolates. Additionally, blaTEM (31.8%) and blaOXA-1 (34.6%) were detected, while blaSHV and blaCTX-M-25 group were absent. Phylogenetic analysis of 107 isolates revealed a diverse distribution across four phylogroups: A (37.4%), D (22.4%), B1 (14.0%), and B2 (5.7%). The predominance of phylogroup A, mainly associated with intestinal commensal carriage, suggests fecal contamination as a primary source.

Senegal↗
PubMed2025

Clinical carbapenem-resistant Enterobacterales in a University Hospital in Dakar, Senegal: genomic insights into Enterobacter hormaechei ST182 strains carrying blaNDM-5 and blaOXA-48 genes .

Senegal has witnessed the emergence and spread of carbapenem-resistant Enterobacterales (CRE), which often cause deadly infections. Accordingly, this study aimed to determine the antimicrobial susceptibility and prevalence of carbapenemases, as well as to perform a whole-genome sequence analysis of clinical CRE isolates from a university hospital in Dakar, Senegal. MALDI-TOF MS and VITEK2 systems were used for bacterial identification and antimicrobial susceptibility testing (AST). Carbapenemase- and cephalosporinase-encoding genes were screened using simplex end-point polymerase chain reaction. Whole-genome sequencing (WGS) was performed using the Illumina MiSeq platform. The CRE isolates were resistant to almost all the 34 antimicrobials tested. Nevertheless, colistin and amikacin remained active, with susceptibility rates of 96% and 71%, respectively. Only the carbapenemase genes blaOXA-48 (53.8%; 15/28) and blaNDM (35.7%; 10/28) and the cephalosporinase gene blaCMY-1 (25%; 7/28) were identified. In this context, two extensively drug-resistant Enterobacter hormaechei isolates were subjected to WGS analysis. These isolates were assigned as sequence type (ST) 182 and carried several genes related to antimicrobial resistance (AMR), metal tolerance, and virulence. An IncL/M plasmid with 61,054 bp in length was identified as carrying the blaOXA-48 gene, whereas an IncFIB(pECLA)/IncFII(pECLA)/IncX3 mutireplicon plasmid with 217,745 bp in length was detected as harboring the blaNDM-5 gene and other genes related to AMR and metal tolerance. Our study presents the first landscape of clinical CRE circulating in Senegal, along with additional genomic analysis of E. hormaechei ST182 strains, which could be useful for mitigating the burden associated with CRE in this country.IMPORTANCEThe investigation of global critical priority CRE isolates has become crucial to reduce morbidity and mortality associated with AMR. This study revealed that colistin and amikacin can be considered good alternatives for treating CRE-associated infections in Dakar. In addition, the genomic approach revealed that the CRE isolates carried both a wide resistome and virulome. Moreover, the abundance of horizontal gene transfer regions in the genomes suggests the great implications of mobile genetic elements in the spread of AMR in Dakar. Furthermore, this study reported the complete sequences of chromosomes and blaOXA-48 and blaNDM-5-carrying plasmids. Our findings are of great importance because complete genome sequences are still rarely characterized in the West African region. Finally, this study highlights the importance of strengthening genomic surveillance of CRE in sub-Saharan African countries to mitigate the burden associated with these pathogens.

Senegal↗