Prevalence and Genomic Investigation of Salmonella Isolates Associated with Watermelons and Their Environmental Reservoirs in Bejaia, Algeria.

This study was conducted in Bejaia, Algeria, to determine the presence of Salmonella in fresh watermelon (n = 105), soil (n = 23), and irrigation water samples (n = 17) collected from two different farms. After isolation, antimicrobial susceptibility testing, serotype determination, multilocus sequence typing, antimicrobial resistance genes detection, and whole genome sequencing were performed. Twenty watermelon samples (19%) were contaminated with Salmonella, but none were found in the soil or irrigation water. Among the 20 Salmonella isolates, 2 serovars were identified (Salmonella Liverpool and Salmonella Anatum), belonging to sequence types ST1959 and ST64, respectively. Ten Salmonella isolates showed significant resistance to nalidixic acid, ofloxacin, and ciprofloxacin but were susceptible to all other antibiotics. The coexistence of point mutations (parC:p.T57S) in Quinolone Resistance-Determining Regions and the qnrB19 gene may contribute to quinolone resistance. The study identified 164 virulence genes in the Salmonella isolates. Our study found Salmonella in fresh watermelon during the preharvest season in Bejaia, Algeria. Our study indicates a relatively high prevalence of Salmonella on watermelon samples before harvest. Although we cannot directly compare our results with previous studies, it is crucial to recognize that the absence of comprehensive comparative data underscores the need for further research and surveillance.

Chemical Composition and Synergistic Potential of Mentha pulegium L. and Artemisia herba alba Asso. Essential Oils and Antibiotic against Multi-Drug Resistant Bacteria.

The essential oils were obtained by hydrodistillation from aerial parts of Mentha pulegium L. (M. pulegium L.) and Artemisia herba alba (A. herba alba) Asso. and analyzed by gas chromatography-flame ionization detector chromatograpy (GC-FID) and gaz chromatography-mass spectrometry (GC-MS). The antibacterial activities of the oils were determined by the disk diffusion method and a microdilution broth assay against six bacteria stains. The combinations of these essential oils with antibiotics were evaluated against two multi-drug-resistant bacteria strains: imipenem-resistant Acinetobacter baumannii (IRAB S3310) and methicillin-resistant Staphylococcus aureus (MRSA S19). The chemical analysis of M. pulegium essential oil revealed the presence of pulegone (74.8%) and neoisomenthol (10.0%). A. herba alba essential oil was characterized by camphor (32.0%), α-thujone (13.7%), 1,8-cineole (9.8%), ß-thujone (5.0%), bornéol (3.8%), camphene (3.6%), and p-cymene (2.1%). All strains tested except Pseudomonas aeruginosa were susceptible to these oils. The combinations of essential oils with antibiotics exerted synergism, antagonism, or indifferent effects. The best effect was observed with A. herba alba essential oil in association with cefoxitin (CX) against MRSA S19. However, for IRAB S3310, the strongest synergistic effect was observed with M. pulegium in association with amikacin (AK). This study demonstrated that M. pulegium and A. herba alba essential oils have antibacterial activities which could be potentiated by antibiotics especially in the case of IRAB S3310.

OXA-48-producing Enterobacterales in different ecological niches in Algeria: clonal expansion, plasmid characteristics and virulence traits.

OBJECTIVES: To investigate the prevalence and molecular characteristics of OXA-48-carbapenemase-producing Enterobacterales strains recovered from various ecological niches in Algeria. METHODS: In total, 3309 samples were collected from different ecological niches (human carriage, animal farms, wild animals, pets, food products, aquatic environment and wastewater treatment plants) distributed among six provinces in Algeria between December 2015 and April 2017. The potential presence of OXA-48-producing Enterobacterales isolates was screened on selective medium. Resistance and virulence profiles were characterized by PCR and sequencing. The clonal relatedness of the different isolates was studied using Rep-PCR and MLST. Conjugation was performed for all OXA-48-producing isolates. The plasmids were analysed by PCR-based replicon typing and WGS. RESULTS: A total of 78 OXA-48-producing Enterobacterales isolates were detected from 3309 samples (2.4%). OXA producers were observed in all the screened sources. The blaCTX-M-15 gene was only observed in two isolates. Clonality analysis revealed distinct lineages of the isolates and a clonal expansion of Klebsiella pneumoniae ST13. K. pneumoniae and Escherichia coli had few virulence factors. Plasmid analysis confirmed that all the isolates harboured a very similar transferable plasmid (belonging to IncL) with a similar structure to the pOXA-48a plasmid carried by K. pneumoniae strain Kp11978. CONCLUSIONS: This study suggests a global dissemination of OXA-48-producing Enterobacterales in different niches due mainly to the spread of an epidemic plasmid. Furthermore, it clearly shows that K. pneumoniae and commensal E. coli can be reservoirs of the blaOXA-48 gene, contributing to the dissemination and transfer of this gene to diverse bacteria among different sources.

First Description of Two Sequence Type 2 Acinetobacter baumannii Isolates Carrying OXA-23 Carbapenemase in Pagellus acarne Fished from the Mediterranean Sea near Bejaia, Algeria.

To determine the occurrence of carbapenem-resistantAcinetobacter baumanniiin fish fished from the Mediterranean Sea near the Bejaia coast (Algeria), we studied 300 gills and gut samples that had been randomly and prospectively collected during 1 year. After screening on selective agar media, using PCR arrays and whole-genome sequencing, we identified for the first time two OXA-23-producingA. baumanniistrains belonging to the widespread sequence type 2 (ST2)/international clone II and harboring aminoglycoside-modifying enzymes [aac(6')-Ib andaac(3')-I genes].

Extended spectrum ß-lactamase and plasmid mediated quinolone resistance in Escherichia coli fecal isolates from healthy companion animals in Algeria.

The aim of this study was to evaluate the rate of fecal carriage of Escherichia coli strains producing Extended-spectrum ß-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR) isolated from healthy pets (dogs and cats) in Algeria. Fecal samples from 171 healthy pets (102 dogs and 69 cats) in one veterinary practice and private owners were included. After isolates identification, antibiotic susceptibility was determined by disk diffusion procedure. ESBL were detected by combination disk tests. PCR and sequencing were used to characterize genes encoding ESBLs and PMQR. Transfer of ESBL and PMQR genes was assessed by conjugation experiments. Phylogenetic groups of E. coli were determined by PCR. Of the 171 animals, 20 carried an ESBL producing E. coli giving a prevalence of ESBL fecal carriage of 11.7%. All isolates were susceptible to carbapenems, cefoxitin, piperacillin-tazobactam, amikacin and fosfomycine. For the rest of the tested ß-lactams, susceptibility rates ranged from 35% to 70% for cefepime and amoxicillin-clavulanic acid respectively. Concerning the non-beta-lactams antibiotics, the rates of susceptibility ranged between 5% to trimethoprim and 95% for chloramphenicol. The beta-lactamase genes identified in E. coli isolates were blaCTX-M-15, blaCTX-M-1, blaSHV-12 and blaTEM-1. The PMQR determinants aac(6')-Ib-cr, qnrS1 and qnrB5 genes were identified in 15 isolates. Transconjugants were obtained for two isolates. Phylogenetic analysis showed that E. coli isolates belong to commensal phylogroups of A and B1. We reported here for the first time in Algeria ESBL and PMQR-producing E. coli in healthy cats and dogs.

First report of 16S rRNA methylase ArmA-producing Acinetobacter baumannii and rapid spread of metallo-ß-lactamase NDM-1 in Algerian hospitals.

PURPOSE: The aim of the present study was to characterize the molecular support of resistance to carbapenems, aminoglycosides and fluoroquinolones in carbapenem-resistant Acinetobacter baumannii clinical isolates recovered between January 2011 and April 2013 from Algerian hospitals. METHODS: Antibiotic susceptibility testing was performed using disk diffusion and Etest methods. Carbapenemase activity was detected using both MALDI-TOF mass spectrometry assay and via microbiological tests. Carbapenem, aminoglycoside and fluoroquinolone resistance determinants were studied by PCR and sequencing. Clonal relationships between strains were determined using Multi Locus Sequence Typing (MLST). RESULTS: A total of 47 imipenem-resistant A. baumannii were isolated and identified by MALDI-TOF mass spectrometry. All imipenem-resistant strains were positive in the modified Hodge test, and EDTA inhibited the activity of metallo-ß-lactamases enzymes in 11 strains. The blaOXA-23 gene was detected in 33 strains and the blaOXA-24 gene in 10 strains. The metallo-ß-lactamase blaNDM-1 gene was detected in 11 isolates (23.4%) from Algiers and Sétif, including 7 that co-expressed a blaOXA-23 gene. Resistance to aminoglycosides was due to the production of aminoglycoside-modifying enzymes, AAC(3)-Ia, AADA, ANT(2″)-I, APH(3')-VI, and 16S rRNA methylases, ArmA. The fluoroquinolone resistance was mainly associated with mutations at Ser83Leu and Ser80Leu of the gyrA and parC genes, respectively. MLST revealed five sequence types (STs), 1, 2, 19, 25, and 85. The imipenem-resistant A. baumannii ST2 was the predominant clone (35/47). CONCLUSIONS: Here we report for the first time clinical multidrug-resistant A. baumannii isolates harboring 16S rRNA methylase gene, armA, and rapid spread of metallo-ß-lactamase NDM-1 isolated from patients in Algeria.

Prevalence and characterization of Carbapenem-Resistant Enterobacterales among inpatients and outpatients in Skikda, Algeria.

INTRODUCTION: The spread of Carbapenemase-producing Enterobacterales (CPEs) has become a significant concern in Algeria, with limited data available on their presence in community settings. This research investigated the resistance mechanisms of carbapenem-resistant Enterobacterales (CREs) collected from hospitals and the community in Skikda city, Algeria, between December 2020 and June 2022. METHODOLOGY: The study collected Enterobacterales strains resistant to ertapenem from inpatient and outpatient populations. An automated system was used for identification and antibiotic susceptibility testing. ß-lactamase production was evaluated through phenotypic tests and confirmed by standard PCR. Lastly, the carbapenemase genes were sequenced using the Sanger method. RESULTS: 17 CRE were isolated, with 9 from inpatients and 8 from outpatients. These isolates belonged to four species: Klebsiella pneumoniae (n = 8), Escherichia coli (n = 6), Enterobacter cloacae (n = 1), and Proteus mirabilis (n = 1). Of 15 CPEs, 11 were extended-spectrum ß-lactamases (ESBLs) positive, 5 were plasmid-mediated cephalosporinase (AmpC) positive, and 1 harbored all three ß-lactamases. All metallo-ß-lactamase-producing strains carried the New Delhi metallo-beta-lactamase gene (blaNDM), including 5 NDM-1 and 7 NDM-5 variants. The presence of blaOXA-48 and blaOXA-244 was observed in one outpatient strain each. NDM was associated with Cefotaximase Munich (CTX-M) ESBL in 8 isolates, while Cephamycinase (CMY) was detected in 3 NDM-5-producing E. coli. CONCLUSIONS: This research highlights the rising prevalence of carbapenemases NDM-1 and NDM-5 among inpatients and outpatients and supports the notion that OXA-48 is becoming increasingly widespread beyond Algerian hospitals.

Panton-Valentine leukocidin positive sequence type 80 methicillin-resistant Staphylococcus aureus carrying a staphylococcal cassette chromosome mec type IVc is dominant in neonates and children in an Algiers hospital.

Methicillin-resistant Staphylococcus aureus (MRSA) is a major antimicrobial drug-resistant pathogen causing serious infections. It was first detected in healthcare settings, but in recent years it has also become disseminated in the community. Children and young adults are most susceptible to infection by community-acquired (CA) MRSA strains. In this study 25 MRSA isolates implicated in infections of neonates and children admitted to an Algiers hospital during an 18 month period were characterized by molecular methods including staphylococcal cassette chromosome (SCC) mec typing, PCR amplification of pvl genes, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Fifteen out of 25 isolates were from hospital-acquired infections. Twenty-four isolates carried SCCmec type IVc and belonged to the sequence type (ST) 80, one isolate carried SCCmec type II and was ST 39. Twenty-two out of 24 ST80-MRSA-IVc isolates carried pvl genes. Our results suggest that the Panton-Valentine leukocidin positive ST80- MRSA-IVc is the dominant MRSA clone causing disease in neonates and children in Algiers.

Nontyphoid Salmonella in farm animals and food products in the Middle East and North Africa: a systematic review.

Aim: This study aimed to document the prevalence, serotype distribution and antibiotic resistance of nontyphoidal Salmonella in animal food products from Middle East/North Africa (MENA) countries. Methods: Peer-reviewed articles published from 1 January 2011 to 7 March 2023 were included and the data were narratively synthesized and statistically analyzed to estimate and compare the overall prevalence. Results: The authors found a high prevalence of Salmonella in MENA countries (12.80%), with the highest prevalence in Lebanon (41.10%). Poultry had a higher prevalence of Salmonella (14.49%) than livestock (9.62%). Salmonella enteritidis was the most commonly identified serotype (21.99%), and sulfamethoxazole had the highest resistance rate (78.81%). Conclusion: The authors emphasize the importance of implementing control measures in MENA countries to limit the spread of the Salmonella pathogen.

Antimicrobial Resistance Among Gram-Negative Bacteria Isolated in the Newborn Intensive Care Unit at Abderrezak-Bouhara Hospital of Skikda, Algeria.

Background: This study aimed to determine the epidemiology of gram-negative bacteria (GNB) isolated in the newborn intensive care unit (NICU) population, to assess their antibiotic susceptibility patterns and possible associated risk factors. Methods: All neonates admitted to the NICU of Abderrezak-Bouhara hospital (Skikda, Algeria) with a clinical diagnosis of neonatal infections from March to May 2019 were included in the study. The extended-spectrum ß-lactamase (ESBLs), plasmidic cephalosporinase (pAmpC), and carbapenemases genes were screened by polymerase chain reaction (PCR) and sequencing. PCR amplification of oprD among carbapenem-resistant Pseudomonas aeruginosa isolates was also performed. The clonal relatedness of the ESBLs isolates was studied using multilocus sequence typing (MLST). Results: Among 148 clinical specimens, 36 (24.3%) GNB strains were isolated from urine (n = 22), wound (n = 8), stool (n = 3), and blood (n = 3) samples. The bacterial species identified were Escherichia coli (n = 13), Klebsiella pneumoniae (n = 5), Enterobacter cloacae (n = 3), Serratia marcescens (n = 3), Salmonella spp. (n = 3), Proteus mirabilis (n = 1), P. aeruginosa (n = 5), and Acinetobacter baumannii (n = 3). PCR and sequencing showed that eleven Enterobacterales isolates harbored the blaCTX-M-15 gene, two E. coli isolates harbored the blaCMY-2 gene, and three A. baumannii isolates harbored both blaOXA-23 and blaOXA-51 genes. Also, five strains of P. aeruginosa were found to harbor mutations in the oprD gene. MLST showed that the K. pneumoniae strains belonged to ST13 and ST189, E. coli belonged to ST69, and E. cloacae belonged to ST214. Different risk factors that could predict positive GNB cultures were found, including female sex, Apgar score <8 at 5 min of life, enteral nutrition, antibiotic use, and extended length of hospitalization. Conclusion: Our study highlights the importance of determining the epidemiology of pathogens causing neonatal infections, their sequence types (ST), and their antibiotic susceptibility patterns to address rapidly a correct antibiotic treatment regimen.

Comprehensive Genomic Characterization of Antibiotic Resistance, Virulence, and Clonality in Salmonella Isolates from Wild Animals in Algeria.

This study investigated Salmonella spp. in wild animals in Algeria, focusing on their prevalence, serotypes, antibiotic resistance, and virulence profiles. From fecal samples collected between May 2021 and June 2022, 1.9% showed Salmonella shedding. The identified serotypes included S. Bredeney, S. Enteritidis, S. Altona, and S. Virchow. Except for S. Altona, all isolates were resistant to quinolones, with S. Bredeney strains, exhibiting multidrug resistance. Whole-genome sequencing revealed various resistance genes and mutations in gyrA or parC genes. Additionally, plasmids IncX1 and ColpVC were detected in several isolates. A comprehensive analysis identified 201 virulence genes. These findings contribute to understanding Salmonella in wild animal populations and their potential impact on public health.

Characterization of extended-spectrum beta-lactamase-producing Salmonella enterica serotype Brunei and Heidelberg at the Hussein Dey hospital in Algiers (Algeria).

The purpose of this work was to study the genetic determinants responsible for extended-spectrum cephalosporin (ESC) resistance of Salmonella collected during the period of 1995-2008 at the Hussein Dey hospital in Algiers (Algeria). Fourteen ESC-resistant Salmonella isolates were tested towards 22 antimicrobial agents. Polymerase chain reaction (PCR) and sequencing were used to determine the underlying genetic determinants responsible for the extended-spectrum beta-lactamase (ESBL) phenotypes. Enterobacterial Repetitive Intergenic Consensus PCR was employed to type the isolates. All tested isolates were resistant to ticarcillin, ticarcillin-clavulanate, piperacillin, cefuroxime, aztreonam, ceftazidime, cefotaxime (except two isolates), cefepime, and cefpirome. PCR and DNA sequencing identified these ESBLs as TEM-48 (n=6), TEM-4 (n=3), CTX-M-15 (n=4), and one new TEM, designated TEM-188. Thus, continued surveillance for the presence of ESBL-producing (non-typhoidal) salmonellae in Algeria is essential.

Whole Genome Sequencing of Extended-Spectrum Beta-Lactamase-Producing Klebsiella pneumoniae Isolated from Neonatal Bloodstream Infections at a Neonatal Care Unit, Algeria.

Aims: Neonatal bloodstream infections (BSIs) are an important cause of mortality among neonates. Besides, extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-Kp) is one of the most frequent pathogens causing neonatal BSIs. This study aimed to characterize ESBL-Kp strains recovered from neonatal BSI and to investigate risk factors associated with ESBL-Kp BSI at the neonatal care unit of Elmeki Hospital, Bejaia, Algeria. Methodology: After isolation, identification, and antibiotic susceptibility testing, the ESBL-Kp strains were characterized by whole genome sequencing. The genomes were then analyzed using bioinformatic tools to determine the resistome, virulome, and phylogenetic relatedness. Results: From September 2019 to May 2020, 27 (8.2%) out of 328 neonates were infected by ESBL-Kp strains. These strains displayed a multidrug-resistant phenotype, and on further investigation, were found to carry an array of antibiotic resistance genes. All ESBL-Kp strains harbored the blaCTX-M-15 gene. Using in silico multilocus sequence typing analysis, six sequence types (STs) were detected with ST268 being the most frequent (56%, n = 15) indicating a local outbreak, confirmed by single nucleotide polymorphism analysis. The yersiniabactin and colibactin gene clusters were identified in six and two ESBL-Kp strains, respectively. Conclusion: This study showed a high prevalence of CTX-M-15-producing K. pneumoniae strains coharboring different antibiotic resistance mechanisms from neonatal BSIs in Algeria. Screening of health care personnel and mothers for ESBL carriage before delivery, isolation of carriers, barrier precautions, antimicrobial usage, and control of hygiene are needed to prevent the dissemination of these pathogens.

Effect of Nanoencapsulation on the Antimicrobial and Antibiofilm Activities of Algerian Origanum glandulosum Desf. against Multidrug-Resistant Clinical Isolates.

The emergence of multidrug-resistant (MDR) bacteria is a danger to public health and exposes patients to high risk, increasing morbidity and mortality worldwide. For this purpose, three months of evaluation of MDR's prevalence and antimicrobial susceptibility patterns in the military regional university hospital of Constantine from different services and samples was carried out. Among a total of 196 isolates, 35.2% were MDR. The use of essential oils such as Origanum glandulosum Desf. as an alternative to antibiotics is attractive due to their rich content of bioactive compounds conferring many biological activities. Also, to overcome the drawbacks of using oils as the hydrophobicity and negative interaction with the environmental conditions, in addition to increasing their activity, encapsulation for the oil was performed using high-speed homogenization (HSH) into nanocapsules and high-pressure homogenization (HPH) into nanoemulsion. Nine volatile constituents were determined using gas chromatography-mass spectrometry analysis (GC-MS) in hydrodistilled oil with thymol, carvacrol, p-cymene, and γ-terpinene as dominants. A dramatic decrease in the major volatile components was observed due to the use of HSH and HPH but generated the same oil profile. The mean particle size of the nanoemulsion was 54.24 nm, while that of nanocapsules was 120.60 nm. The antibacterial activity of the oil and its nanoparticles was estimated on MDR isolates using the disk diffusion, aromatogram, and broth microdilution methods. Consistent with the differences in volatile constituents, the oil exhibited a higher antibacterial activity compared to its nanoforms with the diameters of the inhibition zone against E. coli (20 mm), S. aureus (35 mm), and A. baumannii (40 mm). Both formulations have shown relatively significant activity against the biofilm state at sub-inhibitory concentrations, where nanoemulsion was more potent than nanocapsules. The results obtained suggested that nanoformulations of essential oils are strongly recommended for therapeutic application as alternatives to antibiotics.

Plasmid-Determined Colistin Resistance in the North African Countries: A Systematic Review.

We have conducted a systematic review to update available information on plasmid-mediated colistin resistance (mobilized colistin resistance [mcr]) genes in North African countries. We have searched the articles of PubMed, Scopus, and Web of Science databases reporting plasmid-mediated colistin resistance bacteria isolated in North African countries. After searching and selection, 30 studies that included 208 mcr-positive isolates were included. Different mcr-positive strains frequencies were recorded and ranged from 2% in clinical isolates to 12.3% in environmental samples. Escherichia coli was the predominant species recorded and these microorganisms showed high resistance to ciprofloxacin and cotrimoxazole. IncHI2 plasmids are probably the key vectors responsible for the dissemination of mcr genes in these countries. This review highlighted that the mcr-positive isolates are circulating in different ecological niches with different frequencies. Therefore, actions should be implemented to prevent the dissemination of the mcr genes within and outside of these countries, such as microbiological and molecular surveillance programs and restriction use of colistin in farming.

Epidemiological and Genetic Features of Plasmids Carrying blaNDM Genes: An In Silico Analysis with Emphasis on Replicon Types, and Resistome.

Background: New Delhi metallo-ß-lactamase (NDM) is a metallo-ß-lactamase that has been disseminated worldwide. Plasmids harboring the blaNDM gene belonged to many incompatibility groups, of which IncX3, IncF, and IncA/C were the most represented. This in silico study aimed at analyzing a set of 649 plasmids carrying NDM-type carbapenemase (pNDMs) previously assigned in GenBank. Materials and Methods: The selected plasmids were analyzed by ResFinder (antibiotic resistome identification), BacMet (metal/biocides resistome identification), PlasmidFinder/PLSDB (replicon typing), TAfinder (toxin-antitoxin system [TAS] identification), and OriTfinder (prediction of the transferability). Results: We found that Escherichia coli and Klebsiella pneumoniae amounted to about 68.6% of all reported species. The distribution of these plasmids by samples showed a diversity of origins. Many plasmids carried different genes encoding resistance to antibiotics, heavy metals, and biocides with different frequencies. The TAfinder allowed the identification of a TAS in 292 plasmids (45%). Twenty-four different incompatibility groups were predicted, of which IncX3 (34.2%; n = 222), IncC (10.9%, n = 71), and IncFII (9.9%, n = 64) were the most often described. Besides, 23.6% (n = 151) of pNDMs were recognized as multireplicon plasmids. Conclusion: This study has shown the importance of plasmids in the dissemination of the NDM carbapenemase and raises the importance of monitoring these elements to better understand the evolution of the antibiotic resistance threat.

Fitness Cost of Antibiotic Resistance in Staphylococcus aureus: A Systematic Review.

Background: Recent reports have shown the potential of Staphylococcus aureus for acquiring resistance to last-resort antibiotics. However, most antibiotic resistance mechanisms were associated with a fitness cost that was typically observed as a reduced bacterial growth rate. This systematic review aimed to address the fitness cost of antibiotic resistance in S. aureus that emerged by mutations. Methods: A systematic review was conducted after searching in two databases (PubMed and Scopus) using specific keywords. We included peer-reviewed articles published only in English. All studies describing the fitness cost associated with antibiotic resistance in S. aureus were selected. For each article, the results of fitness testing, minimum inhibition concentrations of mutants, the position of mutation, and the appearance of compensatory mutations were recorded. Results: At all, 35 articles were recorded in the final analysis examining the fitness cost associated with antibiotic resistance in S. aureus that conferred by mutations. Analysis of the data showed that 26 studies reported that the emergence of antibiotic resistance was frequently associated with a fitness cost. Conclusion: This review summarized that the antibiotic resistance selection caused in the majority of cases a substantial fitness cost. Further in vivo experiments revealed that these mutations affected bacterial virulence and the ability to establish a successful infection.

First Report of CC5-MRSA-IV-SCCfus "Maltese Clone" in Bat Guano.

Methicillin-resistant Staphylococcus aureus (MRSA) is a widespread pathogen that could cause different illnesses in both human and animals. Presence of MRSA in animals raises concerns of their capacity to act as reservoirs, particularly in wild animals. This study aimed to characterize the resistance and virulence patterns of S. aureus strains isolated from bat guano in Algeria. From March to May 2016, 98 bat guano samples from Aokas's cave (Bejaia, Algeria) were collected. Swabs were taken for microbiological studies. Isolates were identified by Vitek® MS system, and antibiotic susceptibility was determined by disk diffusion method. The clonal origin, virulence and antibiotic resistance profiles of S. aureus isolates were characterized by whole genome sequencing. Eleven S. aureus strains were obtained from the 98 guano samples. Seven isolates were sensitive to all antibiotics tested and four (36.3%) were resistant to penicillin G, cefoxitin and fusidic acid. The four MRSA isolates were assigned to the sequence type ST149 and related to spa type t010. These isolates harbored a SCCmecIV element and the fusidic acid resistance element Q6GD50 (fusC). They carried different virulence genes including several enterotoxins (sea, egc enterotoxin locus, sec, sel), and the toxic shock syndrome toxin (tst). Our results highlight that bat guano may constitute an important reservoir of MRSA strains.

Spread of OXA-48 and NDM-1-Producing Klebsiella pneumoniae ST48 and ST101 in Chicken Meat in Western Algeria.

Aim: We investigated the prevalence of carbapenemase-producing Enterobacteriaceae (CPE) in chicken meat in Western Algeria in 2017. Results: From February to July 2017, samples of chicken meat from three poultry farms in Western Algeria were screened for the presence of CPE. Strains were characterized with regard to antibiotic resistance, ß-lactamase content, Plasmid-mediated quinolone resistance, sulfonamide resistance genes, clonality (repetitive sequence-based profiles and multilocus sequence typing) and virulence traits. Of 181 samples analyzed, 29 (16.0%) carbapenemase-producing Klebsiella pneumoniae were detected. Twenty-three OXA-48-producers (79.3%) and six (20.7%) New Delhi metallo (NDM)-1-producers were observed. Clonality analysis showed three distinct lineages and clonal expansions of the OXA-48-producing K. pneumoniae ST48 and the NDM-1-producing K. pneumoniae ST101. These isolates harbored fimH, ureA, mrkD, entB, uge, and wabG. Neither capsular serotype genes nor hypermucoviscous phenotype were detected. Plasmid analysis confirmed that all these isolates harbored the transferable IncL and IncFIIK plasmids. Conclusions: This study reports the spread of OXA-48 and NDM-1-producing K. pneumoniae ST48 and ST101 in chicken meat in Western Algeria and demonstrates that food represents a reservoir of the carbapenemases encoding genes.