Nadia Safia CHENOUF

Dr. Nadia Safia CHENOUF

Biology, University of Djelfa, Djelfa, Algeria
orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 August 2021 in Antibiotics
Verified
Journal Article
Open access
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Isabel CarvalhoIsabel Carvalho
Isabel Carvalho
RCRita Cunha
Rita Cunha
CMCarla Martins
Carla Martins
SÁSandra Martínez Álvarez
Sandra Martínez Álvarez
NCNadia Safia CHENOUF
Nadia Safia CHENOUF
Patrícia PoetaPatrícia Poeta
Patrícia Poeta
The purpose of this study was to analyse the prevalence and genetic characteristics of ESBL and acquired-AmpC (qAmpC)-producing Escherichia coli isolates from healthy and sick dogs in Portugal. Three hundred and sixty-one faecal samples from sick and healthy dogs were seeded on MacConkey agar supplemented with cefotaxime (2 µg/mL) for cefotaxime-resistant (CTXR) E. coli recovery. Antimicrobial susceptibility testing for 15 antibiotics was performed and the ESBL-phenotype of the E. coli isolates was screened. Detection of antimicrobial resistance and virulence genes, and molecular typing of the isolates (phylogroups, multilocus-sequence-typing, and specific-ST131) were performed by PCR (and sequencing when required). CTXRE. coli isolates were obtained in 51/361 faecal samples analysed (14.1%), originating from 36/234 sick dogs and 15/127 healthy dogs. Forty-seven ESBL-producing E. coli isolates were recovered from 32 sick (13.7%) and 15 healthy animals (11.8%). Different variants of blaCTX-M genes were detected among 45/47 ESBL-producers: blaCTX-M-15 (n = 26), blaCTX-M-1 (n = 10), blaCTX-M-32 (n = 3), blaCTX-M-55 (n = 3), blaCTX-M-14 (n = 2), and blaCTX-M-variant (n = 1); one ESBL-positive isolate co-produced CTX-M-15 and CMY-2 enzymes. Moreover, two additional CTXR ESBL-negative E. coli isolates were CMY-2-producers (qAmpC). Ten different sequence types were identified (ST/phylogenetic-group/β-lactamase): ST131/B2/CTX-M-15, ST617/A/CTX-M-55, ST3078/B1/CTX-M-32, ST542/A/CTX-M-14, ST57/D/CTX-M-1, ST12/B2/CTX-M-15, ST6448/B1/CTX-M-15 + CMY-2, ST5766/A/CTX-M-32, ST115/D/CMY-2 and a new-ST/D/CMY-2. Five variants of CTX-M enzymes (CTX-M-15 and CTX-M-1 predominant) and eight different clonal complexes were detected from canine ESBL-producing E. coli isolates. Although at a lower rate, CMY-2 β-lactamase was also found. Dogs remain frequent carriers of ESBL and/or qAmpC-producing E. coli with a potential zoonotic role.

29 June 2020 in Microbial Drug Resistance
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Journal Article
Closed access
NCNadia Safia CHENOUF
Nadia Safia CHENOUF
Isabel CarvalhoIsabel Carvalho
Isabel Carvalho
CMChafik Redha Messaï
Chafik Redha Messaï
LRLaura Ruiz-Ripa
Laura Ruiz-Ripa
OMOlouwafemi Mistourath Mama
Olouwafemi Mistourath Mama
Carmen TorresCarmen Torres
Carmen Torres
This study aimed to determine the prevalence and diversity of extended-spectrum β-lactamase (ESBL)-producing and multidrug-resistant (MDR) Escherichia coli and Klebsiella pneumoniae isolates from 136 broiler livers randomly purchased in 136 retail markets in Djelfa (Algeria). Isolation was performed on Hektoen agar and bacterial identification was carried out by API20E system and Maldi-TOF-MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry). Antimicrobial susceptibility was tested by the disk diffusion and agar dilution methods. Detection of ESBLs and other resistance and integron genes, phylogenetic grouping, and molecular typing was performed by PCR and sequencing. Seventy-eight isolates (one per positive sample) were recovered: 73 E. coli and 5 K. pneumoniae . Among E. coli , 86.3% of isolates were MDR. ESBL activity was revealed in eight E. coli and five K. pneumonia e isolates (rates of 5.9% and 3.7% in analyzed samples, respectively). ESBL genes detected among E. coli were as follows (number of isolates): bla CTX-M-15 (3), bla CTX-M-1 (3), bla CTX-M-55 (1), and bla SHV-12 (1); all ESBL-producing K. pneumoniae isolates carried the bla CTX-M-15 gene. ESBL-producing E. coli isolates were assigned to lineages (phylogroup/sequence type and number of isolates in parenthesis): A/ST48 (1), B1/ST6448 (1), B1/ST5087 (3), B1/ST23 (1), and B2/ST131 (two bla CTX-M-15 E. coli isolates). K. pneumoniae isolates were ascribed to sequence types ST2010 and ST3483. Regarding the 65 non-ESBL E. coli isolates, the most observed resistance genes were as follows: tet (A) (75%), bla TEM (57.1%), and sul2 (43.5%). Class1 integrons were revealed in seven non-ESBL E. coli isolates (10.7%) and two gene-cassette arrays were identified: dfrA 1 and aadA 1 +dfrA 1. Our study provides evidence that broiler-derived food from Center of Algeria constitutes a source of ESBL and/or MDR-producing Enterobacteriaceae, with detection of relevant ESBL genes and epidemic clones.

1 April 2021 in Comparative Immunology, Microbiology and Infectious Diseases
Verified
Journal Article
Closed access
LMLynda Onyinye Majesty-Alukagberie
Lynda Onyinye Majesty-Alukagberie
Isabel CarvalhoIsabel Carvalho
Isabel Carvalho
NCNadia Safia CHENOUF
Nadia Safia CHENOUF
SMSandra Martínez-Álvarez
Sandra Martínez-Álvarez
MSMadjid Sadi
Madjid Sadi
CTCarmen Torres
Carmen Torres

14 December 2022 in Antibiotics
Verified
Journal Article
Open access
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MBMohamed Belmahdi
Mohamed Belmahdi
NCNadia Safia CHENOUF
Nadia Safia CHENOUF
ABAbdelkrim Ait Belkacem
Abdelkrim Ait Belkacem
SÁSandra Martínez Álvarez
Sandra Martínez Álvarez
Mario Sergio Pino-HurtadoMario Sergio Pino-Hurtado
Mario Sergio Pino-Hurtado
Carmen TorresCarmen Torres
Carmen Torres
Antimicrobial resistance is a global threat that is spreading more and more in both human and animal niches. This study investigates the antimicrobial resistance and virulence threats of Escherichia coli isolates recovered from intestinal and fecal samples of 100 chickens, 60 turkeys, and 30 sparrows. Extended spectrum β-lactamase (ESBL) producing E. coli isolates were recovered in 12 of the animals tested, selecting one isolate per positive animal: sparrow (eight isolates, 26.7%), turkey (three isolates, 5%), and chicken (one isolate, 1%). The E. coli isolates were ascribed to B1 and D phylogenetic groups. The blaCTX-M-14 gene was detected in all ESBL-producing E. coli isolates from sparrow. The blaCTX-M-15 (two isolates) and blaCTX-M-14 genes (one isolate) were detected in the isolates of turkey, and the blaCTX-M-1 gene in one isolate from broiler. Three lineages were revealed among the tested isolates (ST/phylogenetic group/type of ESBL/origin): ST117/D/CTX-M-1/broiler, ST4492 (CC405)/D/CTX-M-15/turkey, and ST602/B1/CTX-M-14/sparrow. All isolates were negative for stx1, sxt2, and eae virulence genes. Our findings provide evidence that the sparrow could be a vector in the dissemination of ESBL-producing E. coli isolates to other environments. This study also reports, to our knowledge, the first detection of blaCTX-M-14 from sparrow at a global level and in turkey in Algeria.

1 March 2021 in Journal of Dairy Science
Verified
Journal Article
Closed access
NCNadia Safia CHENOUF
Nadia Safia CHENOUF
OMOlouwafemi Mistourah Mama
Olouwafemi Mistourah Mama
CMChafik Redha Messaï
Chafik Redha Messaï
LRLaura Ruiz-Ripa
Laura Ruiz-Ripa
RFRosa Fernández-Fernández
Rosa Fernández-Fernández
Carmen TorresCarmen Torres
Carmen Torres
This study was designed to determine antimicrobial resistance phenotypes and genotypes and virulence factors in Staphylococcus aureus and coagulase-negative staphylococci (CNS) in unpasteurized milk sold in Djelfa, Algeria. Eighty-two unpasteurized cow milk samples were randomly obtained from 82 retail stores in Djelfa and tested to detect staphylococci. Species were identified by biochemical tests and MALDI-TOF. Antimicrobial resistance phenotypes and genotypes were determined by disk diffusion test, PCR, and sequencing. The Staph. aureus isolates were subjected to spa typing, multilocus sequence typing, and detection of virulence genes and the scn gene by PCR and sequencing. Forty-five (54.9%) milk samples were contaminated by staphylococci and 45 isolates were recovered: 10 Staph. aureus (12.2% of total samples) and 35 CNS (42.7%). Resistance to penicillin (blaZ), tetracycline (tetL/tetK), and erythromycin (ermB/msrA/ermC) were the most common phenotypes (genotypes). Three CNS were methicillin-resistant and all were mecA-positive. The Staph. aureus isolates were ascribed to the following lineages [spa type/sequence type/associated clonal complex (number of isolates)]: t267/ST479/CC479 (n = 6), t1510/ST5651/CC45 (n = 1), t359/ST97/CC97/ (n = 1), t346/ST15/CC15 (n = 1), and t044/ST80 (n = 1). The mecA gene was detected in the cefoxitin-susceptible t044/ST80 isolate and co-harbored the lukF/lukS-PV and scn genes. The detection of mecA-PVL-positive Staph. aureus, methicillin-resistant CNS, and multidrug-resistant staphylococcal species indicates a potentially serious health issue and reveals that unpasteurized milk sold in Djelfa city could be a potential vehicle for pathogenic and antimicrobial-resistant staphylococci.

22 June 2020 in Journal of Food Protection
Verified
Journal Article
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MSMargarida Sousa
Margarida Sousa
Vanessa SilvaVanessa Silva
Vanessa Silva
ASAdriana Silva
Adriana Silva
NSNuno Silva
Nuno Silva
JRJessica Ribeiro
Jessica Ribeiro
Patrícia PoetaPatrícia Poeta
Patrícia Poeta
The prevalence and diversity of Staphylococcus species from wild European rabbits (Oryctolagus cuniculus) in the Azores were investigated, and the antibiotic resistance phenotype and genotype of the isolates were determined. Nasal samples from 77 wild European rabbits from São Jorge and São Miguel islands in Azores were examined. Antibiotic susceptibility of the isolates was determined using the Kirby-Bauer disk diffusion method, and the presence of antimicrobial resistance genes and virulence factors was determined by PCR. The genetic lineages of S. aureus isolates were characterized by spa typing and multilocus sequence typing. A total of 49 staphylococci were obtained from 35 of the 77 wild rabbits. Both coagulase-positive (8.2%) and coagulase-negative (91.8%) staphylococci were detected: 4 S. aureus, 17 S. fleurettii, 13 S. sciuri, 7 S. xylosus, 4 S. epidermidis, and 1 each of S. simulans, S. saprophyticus, S. succinus, and S. equorum. The four S. aureus isolates showed methicillin susceptibility and were characterized as spa type t272/CC121, Panton-Valentine leukocidin negative, and hlB positive. Most of the coagulase-negative staphylococci showed resistance to fusidic acid and beta-lactams, and multidrug resistance was identified especially among S. epidermidis isolates. The mecA gene was detected in 20 isolates of the species S. fleurettii and S. epidermidis, associated with the blaZ gene in one S. epidermidis isolate. Five antimicrobial resistance genes were detected in one S. epidermidis isolate (mecA,dfrA,dfrG,aac6′-aph2′′, and ant4). Our results highlight that wild rabbits are reservoirs or “temporary hosts” of Staphylococcus species with zoonotic potential, some of them carrying relevant antimicrobial resistances.