# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 2991 | 0 | 0.9720 | Occurrence and antimicrobial resistance of Salmonella species and potentially pathogenic Escherichia coli in free-living seals of Canadian Atlantic and eastern Arctic waters. Seal populations in Canadian waters provide sustenance to coastal communities. There is potential for pathogenic and/or antimicrobial-resistant bacteria to transfer to humans through inadvertent faecal contamination of seal products. The objective of this study was to investigate the occurrence and potential antimicrobial resistance of Salmonella spp., Escherichia coli and Listeria monocytogenes in faecal samples collected from grey seals (Halichoerus grypus) in the Gulf of St. Lawrence and from ringed seals (Pusa hispida) in Frobisher Bay and Eclipse Sound, Nunavut, Canada. Grey seals were harvested during commercial hunts or during scientific sampling; ringed seals were collected by Inuit hunters during subsistence harvests. Virulence genes defining pathogenic E. coli were identified by PCR, and antimicrobial susceptibility testing was performed on recovered isolates. In grey seals, E. coli was detected in 34/44 (77%) samples, and pathogenic E. coli (extraintestinal E. coli [ExPEC], enteropathogenic E. coli [EPEC] or ExPEC/EPEC) was detected in 13/44 (29%) samples. Non-susceptibility to beta-lactams and quinolones was observed in isolates from 18 grey seals. In ringed seals from Frobisher Bay, E. coli was detected in 4/45 (9%) samples; neither virulence genes nor antimicrobial resistance was detected in these isolates. In ringed seals from Eclipse Sound, E. coli was detected in 8/50 (16%) samples and pathogenic E. coli (ExPEC and ExPEC/EPEC) in 5/50 (10%) samples. One seal from Eclipse Sound had an E. coli isolate resistant to beta-lactams. A monophasic Salmonella Typhimurium was recovered from 8/50 (16%) seals from Eclipse Sound. All Salmonella isolates were resistant to ampicillin, streptomycin, sulfisoxazole and tetracycline. L. monocytogenes was not detected in any sample. These findings suggest that seals may act as important sentinel species and as reservoirs or vectors for antimicrobial-resistant and virulent E. coli and Salmonella species. Further characterization of these isolates would provide additional insights into the source and spread of antimicrobial resistance and virulence genes in these populations of free-living seals. | 2023 | 37317052 |
| 1264 | 1 | 0.9685 | Characterization of mannitol-fermenting methicillin-resistant staphylococci isolated from pigs in Nigeria. This study was conducted to determine the species distribution, antimicrobial resistance pheno- and genotypes and virulence traits of mannitol-positive methicillin-resistant staphylococci (MRS) isolated from pigs in Nsukka agricultural zone, Nigeria. Twenty mannitol-positive methicillin-resistant coagulase-negative staphylococcal (MRCoNS) strains harboring the mecA gene were detected among the 64 Staphylococcus isolates from 291 pigs. A total of 4 species were identified among the MRCoNS isolates, namely, Staphylococcus sciuri (10 strains), Staphylococcus lentus (6 strains), Staphylococcus cohnii (3 strains) and Staphylococcus haemolyticus (one strain). All MRCoNS isolates were multidrug-resistant. In addition to β-lactams, the strains were resistant to fusidic acid (85%), tetracycline (75%), streptomycin (65%), ciprofloxacin (65%), and trimethoprim/sulphamethoxazole (60%). In addition to the mecA and blaZ genes, other antimicrobial resistance genes detected were tet(K), tet(M), tet(L), erm(B), erm(C), aacA-aphD, aphA3, str, dfrK, dfrG, cat pC221, and cat pC223. Thirteen isolates were found to be ciprofloxacin-resistant, and all harbored a Ser84Leu mutation within the QRDR of the GyrA protein, with 3 isolates showing 2 extra substitutions, Ser98Ile and Arg100Lys (one strain) and Glu88Asp and Asp96Thr (2 strains). A phylogenetic tree of the QRDR nucleotide sequences in the gyrA gene revealed a high nucleotide diversity, with several major clusters not associated with the bacterial species. Our study highlights the possibility of transfer of mecA and other antimicrobial resistance genes from MRCoNS to pathogenic bacteria, which is a serious public health and veterinary concern. | 2015 | 26413075 |
| 1265 | 2 | 0.9683 | Coagulase-negative staphylococci (CoNS) isolated from ready-to-eat food of animal origin--phenotypic and genotypic antibiotic resistance. The aim of this work was to study the pheno- and genotypical antimicrobial resistance profile of coagulase negative staphylococci (CoNS) isolated from 146 ready-to-eat food of animal origin (cheeses, cured meats, sausages, smoked fishes). 58 strains were isolated, they were classified as Staphylococcus xylosus (n = 29), Staphylococcus epidermidis (n = 16); Staphylococcus lentus (n = 7); Staphylococcus saprophyticus (n = 4); Staphylococcus hyicus (n = 1) and Staphylococcus simulans (n = 1) by phenotypic and genotypic methods. Isolates were tested for resistance to erythromycin, clindamycin, gentamicin, cefoxitin, norfloxacin, ciprofloxacin, tetracycline, tigecycline, rifampicin, nitrofurantoin, linezolid, trimetoprim, sulphamethoxazole/trimethoprim, chloramphenicol, quinupristin/dalfopristin by the disk diffusion method. PCR was used for the detection of antibiotic resistance genes encoding: methicillin resistance--mecA; macrolide resistance--erm(A), erm(B), erm(C), mrs(A/B); efflux proteins tet(K) and tet(L) and ribosomal protection proteins tet(M). For all the tet(M)-positive isolates the presence of conjugative transposons of the Tn916-Tn1545 family was determined. Most of the isolates were resistant to cefoxitin (41.3%) followed by clindamycin (36.2%), tigecycline (24.1%), rifampicin (17.2%) and erythromycin (13.8%). 32.2% staphylococcal isolates were multidrug resistant (MDR). All methicillin resistant staphylococci harboured mecA gene. Isolates, phenotypic resistant to tetracycline, harboured at least one tetracycline resistance determinant on which tet(M) was most frequent. All of the isolates positive for tet(M) genes were positive for the Tn916-Tn1545 -like integrase family gene. In the erythromycin-resistant isolates, the macrolide resistance genes erm(C) or msr(A/B) were present. Although coagulase-negative staphylococci are not classical food poisoning bacteria, its presence in food could be of public health significance due to the possible spread of antibiotic resistance. | 2015 | 25475289 |
| 1259 | 3 | 0.9682 | Tetracycline resistance potential of heterotrophic bacteria isolated from freshwater fin-fish aquaculture system. AIMS: This study investigated the tetracycline resistance potential of heterotrophic bacteria isolated from twenty-four freshwater fin-fish culture ponds in Andhra Pradesh, India. METHODS AND RESULTS: A total of 261 tetracycline resistant bacteria (tetR) were recovered from pond water, pond sediment, fish gills, fish intestine, and fish feed. Bacteria with high tetracycline resistance (tetHR) (n = 30) that were resistant to tetracycline concentrations above 128 μg mL-1 were predominantly Lactococcus garvieae followed by Enterobacter spp., Lactococcus lactis, Enterobacter hormaechei, Staphylococcus arlettae, Streptococcus lutetiensis, Staphylococcus spp., Brevundimonas faecalis, Exiguobacterium profundum, Lysinibacillus spp., Stutzerimonas stutzeri, Enterobacter cloacae, and Lactococcus taiwanensis. Resistance to 1024 μg mL-1 of tetracycline was observed in L. garvieae, S. arlettae, Enterobacter spp., B. faecalis. Tet(A) (67%) was the predominant resistance gene in tetHR followed by tet(L), tet(S), tet(K), and tet(M). At similar concentrations of exposure, tetracycline procured at the farm level (69.5% potency) exhibited lower inhibition against tetHR bacteria compared to pure tetracycline (99% potency). The tetHR bacteria showed higher cross-resistance to furazolidone (100%) followed by co-trimoxazole (47.5%) and enrofloxacin (11%). CONCLUSIONS: The maximum threshold of tetracycline resistance at 1024 μg mL-1 was observed in S. arlettae, Enterobacter spp., B. faecalis, and L. garvieae and tet(A) was the major determinant found in this study. | 2023 | 36958862 |
| 1318 | 4 | 0.9682 | Assessing the Public Health Implications of Virulent and Antibiotic-Resistant Bacteria in Côte d'Ivoire's Ready-to-Eat Salads. In Côte d'Ivoire, the popularity of ready-to-eat salads has grown substantially. Despite their convenience, these products often face criticism for their microbiological safety. This research was conducted to assess the virulence and antibiotic resistance profiles of Escherichia coli (E. coli), Salmonella spp., and Staphylococcus aureus (S. aureus) isolated from salads available in hypermarkets across Abidjan. The study utilized a combination of microbiological and molecular biology techniques. Results indicated that E. coli isolates harbored virulence genes such as stx2 (50%) and ST (62.50%), though genes stx1 and LT were absent in the samples tested. In S. aureus, virulence genes detected included sea (55.55%), sec (11.110%), and sed (44.44%). The antibiotic resistance assessment revealed high resistance in E. coli to β-lactam antibiotics, with all isolates resistant to cefuroxime (100%) and the majority to ampicillin and cefoxitin (87.5%). Most Salmonella spp. isolates were sensitive to the antibiotics tested, except for cefoxitin and ampicillin, showing resistance rates of 42.85% and 57.15%, respectively. Staphylococcus aureus demonstrated considerable resistance, particularly to cefoxitin (44.44%), benzylpenicillin (100%), and ampicillin (55.55%). In addition, resistance to aminoglycosides (55.55% to both kanamycin and gentamicin) and macrolides (66.66% to erythromycin and 55.55% to clindamycin) was noted. Resistance to various fluoroquinolones ranged between 33.33% and 55.55%. The presence of resistance genes such as blaTEM (10.52%), qnrA (2.26%), qnrB (5.26%), qnrS (5.26%), and mecA (13.15%) in E. coli and S. aureus underscores the challenge of multidrug resistance, exhibiting phenotypes such as ESBL (50%), Meti-R (55.55%), KTG (44.44%), MLSB (44.44%), and FQ-R (25%). These results carry significant epidemiological and public health implications, highlighting the urgent need for improved safety regulations and practices regarding ready-to-eat salads in urban food markets. | 2024 | 39139471 |
| 1222 | 5 | 0.9681 | Molecular Characterization and the Antimicrobial Resistance Profile of Salmonella spp. Isolated from Ready-to-Eat Foods in Ouagadougou, Burkina Faso. The emergence of antimicrobial-resistantfood-borne bacteria is a great challenge to public health. This study was conducted to characterize and determine the resistance profile of Salmonella strains isolated from foods including sesames, ready-to-eat (RTE) salads, mango juices, and lettuce in Burkina Faso. One hundred and forty-eight biochemically identified Salmonella isolates were characterized by molecular amplification of Salmonella marker invA and spiC, misL, orfL, and pipD virulence genes. After that, all confirmed strains were examined for susceptibility to sixteen antimicrobials, and PCR amplifications were used to identify the following resistance genes: bla (TEM), temA, temB, StrA, aadA, sul1, sul2, tet(A), and tet(B). One hundred and eight isolates were genetically confirmed as Salmonella spp. Virulence genes were observed in 57.4%, 55.6%, 49.1%, and 38% isolates for pipD, SpiC, misL, and orfL, respectively. Isolates have shown moderate resistance to gentamycin (26.8%), ampicillin (22.2%), cefoxitin (19.4%), and nalidixic acid (18.5%). All isolates were sensitive to six antibiotics, including cefotaxime, ceftazidime, aztreonam, imipenem, meropenem, and ciprofloxacin. Among the 66 isolates resistant to at least one antibiotic, 11 (16.7%) were multidrug resistant. The Multiple Antimicrobial Resistance (MAR) index of Salmonella serovars ranged from 0.06 to 0.53. PCR detected 7 resistance genes (tet(A), tet(B), bla (TEM), temB, sul1, sul2, and aadA) in drug-resistant isolates. These findings raise serious concerns because ready-to-eat food in Burkina Faso could serve as a reservoir for spreading antimicrobial resistance genes worldwide. | 2022 | 36406904 |
| 1223 | 6 | 0.9681 | Characterization of Escherichia coli virulence genes, pathotypes and antibiotic resistance properties in diarrheic calves in Iran. BACKGROUND: Calf diarrhea is a major economic concern in bovine industry all around the world. This study was carried out in order to investigate distribution of virulence genes, pathotypes, serogroups and antibiotic resistance properties of Escherichia coli isolated from diarrheic calves. RESULTS: Totally, 76.45% of 824 diarrheic fecal samples collected from Isfahan, Chaharmahal, Fars and Khuzestan provinces, Iran were positive for E. coli and all of them were also positive for cnf2, hlyA, cdtIII, f17c, lt, st, stx1, eae, ehly, stx2 and cnf1 virulence genes. Chaharmahal had the highest prevalence of STEC (84.61%), while Isfahan had the lowest (71.95%). E. coli serogroups had the highest frequency in 1-7 days old calves and winter season. Distribution of ETEC, EHEC, AEEC and NTEC pathotypes among E. coli isolates were 28.41%, 5.07%, 29.52% and 3.49%, respectively. Statistical analyses were significant for presence of bacteria between various seasons and ages. All isolates had the high resistance to penicillin (100%), streptomycin (98.25%) and tetracycline (98.09%) antibiotics. The most commonly detected resistance genes were aadA1, sul1, aac[3]-IV, CITM, and dfrA1. The most prevalent serogroup among STEC was O26. CONCLUSIONS: Our findings should raise awareness about antibiotic resistance in diarrheic calves in Iran. Clinicians should exercise caution when prescribing antibiotics. | 2014 | 25052999 |
| 1324 | 7 | 0.9681 | Molecular characterization of antimicrobial resistance in enterococci and Escherichia coli isolates from European wild rabbit (Oryctolagus cuniculus). A total of 44 Escherichia coli and 64 enterococci recovered from 77 intestinal samples of wild European rabbits in Portugal were analyzed for resistance to antimicrobial agents. Resistance in E. coli isolates was observed for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, gentamicin, tobramycin, nalidixic acid, ciprofloxacin and chloramphenicol. None of the E. coli isolates produced extended-spectrum beta-lactamases (ESBLs). The bla(TEM), aadA, aac(3)-II, tet(A) and/or tet(B), and the catA genes were demonstrated in all ampicillin, streptomycin, gentamicin, tetracycline, and chloramphenicol-resistant isolates respectively, and the sul1 and/or sul2 and/or sul3 genes in 4 of 5 sulfamethoxazole/trimethoprim resistant isolates. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (39 isolates), followed by E. faecium (21 isolates) and E. hirae (4 isolates). More than one-fourth (29.7%) of the isolates were resistant to tetracycline; 20.3% were resistant to erythromycin, 14.1% were resistant to ciprofloxacin and 10.9% were resistant to high-level-kanamycin. Lower level of resistance (<10%) was detected for ampicillin, quinupristin/dalfopristin and high-level-gentamicin, -streptomycin. No vancomycin-resistance was detected in the enterococci isolates. Resistance genes detected included aac(6')-aph(2''), ant(6)-Ia, tet(M) and/or tet(L) in all gentamicin, streptomycin and tetracycline-resistant isolates respectively. The aph(3')-IIIa gene was detected in 6 of 7 kanamycin-resistant isolates, the erm(B) gene in 11 of 13 erythromycin-resistant isolates and the vat(D) gene in the quinupristin/dalfopristin-resistant E. faecium isolate. This survey showed that faecal bacteria such as E. coli and enterococci of wild rabbits could be a reservoir of antimicrobial resistance genes. | 2010 | 20624632 |
| 1346 | 8 | 0.9680 | High prevalence of multidrug resistant Escherichia coli isolated from fresh vegetables sold by selected formal and informal traders in the most densely populated Province of South Africa. Contaminated fresh produce has increasingly been implicated in foodborne disease outbreaks. As microbiological safety surveillance in South Africa is limited, a total of 545 vegetable samples (spinach, tomato, lettuce, cucumber, and green beans) were purchased from retailers, street traders, trolley vendors and farmers' markets. Escherichia coli, coliforms and Enterobacteriaceae were enumerated and the prevalence of Escherichia coli, Salmonella spp. and Listeria monocytogenes determined. E. coli isolates were characterized phenotypically (antibiotic resistance) and genotypically (diarrheagenic virulence genes). Coliforms, E. coli and Enterobacteriaceae counts were mostly not significantly different between formal and informal markets, with exceptions noted on occasion. When compared to international standards, 90% to 98% tomatoes, 70% to 94% spinach, 82% cucumbers, 93% lettuce, and 80% green bean samples, had satisfactory (≤ 100 CFU/g) E. coli counts. Of the 545 vegetable samples analyzed, 14.86% (n = 81) harbored E. coli, predominantly from leafy green vegetables. Virulence genes (lt, st, bfpA, eagg, eaeA, stx1, stx2, and ipaH) were not detected in the E. coli isolates (n = 67) characterized, however 40.30% were multidrug-resistant. Resistance to aminoglycosides (neomycin, 73.13%; gentamycin, < 10%), penicillins (ampicillin, 38.81%; amoxicillin, 41.79%; augmentin, < 10%), sulfonamides (cotrimoxazole, 22.39%), tetracycline (19.4%), chloramphenicol (11.94%), cephalosporins (cefepime, 34.33%), and carbapenemases (imipenem, < 10%) were observed. This study highlights the need for continued surveillance of multidrug resistant foodborne pathogens in fresh produce retailed formally and informally for potential consumer health risks. PRACTICAL APPLICATION: The results indicate that the microbiological quality of different vegetables were similar per product type, regardless of being purchased from formal retailers or informal street traders, trolley vendors or farmers' markets. Although no pathogenic bacteria (diarrheagenic E. coli, Salmonella spp. or L. monocytogenes) were isolated, high levels of multidrug-resistance was observed in the generic E. coli isolates. These findings highlight the importance of microbiological quality surveillance of fresh produce in formal and informal markets, as these products can be a reservoir of multidrug resistant bacteria harboring antibiotic resistance and virulence genes, potentially impacting human health. | 2021 | 33294974 |
| 1347 | 9 | 0.9680 | Microbiological quality and antimicrobial resistance characterization of Salmonella spp. in fresh milk value chains in Ghana. Consumer perception of poor hygiene of fresh milk products is a major barrier to promotion of milk consumption as an intervention to alleviate the burden of malnutrition in Ghana. Fresh milk is retailed raw, boiled, or processed into unfermented cheese and spontaneously fermented products in unlicensed outlets. In this study, we have determined microbiological quality of informally retailed fresh milk products and characterized the genomic diversity and antimicrobial resistance (AMR) patterns of non-typhoidal Salmonella (NTS) in implicated products. A total of 159 common dairy products were purchased from five traditional milk markets in Accra. Samples were analysed for concentrations of aerobic bacteria, total and fecal coliforms, Escherichia coli, staphylococci, lactic acid bacteria and yeast and moulds. The presence of Salmonella, E. coli O157:H7, Listeria monocytogenes and Staphylococcus aureus were determined. AMR of Salmonella against 18 antibiotics was experimentally determined. Genome sequencing of 19 Salmonella isolates allowed determination of serovars, antigenic profiles, prediction of AMR genes in silico and inference of phylogenetic relatedness between strains. Raw and heat-treated milk did not differ significantly in overall bacterial quality (P = 0.851). E. coli O157:H7 and Staphylococcus aureus were present in 34.3% and 12.9% of dairy products respectively. Multidrug resistant (MDR) Salmonella enterica serovars Muenster and Legon were identified in 11.8% and 5.9% of unfermented cheese samples respectively. Pan genome analysis revealed a total of 3712 core genes. All Salmonella strains were resistant to Trimethoprim/Sulfamethoxazole, Cefoxitin, Cefuroxime Axetil and Cefuroxime. Resistance to Chloramphenicol (18%) and Ciprofloxacin (100%), which are first line antibiotics used in treatment of NTS bacteremia in Ghana, was evident. AMR was attributed to presence and/or mutations in the following genes: golS, sdiA for cephalosporins, aac(6')-Iy, ant(9) for aminoglycosides, mdtK, gyrA, gyrB, parC, parE for quinolones and cat1, cat4 for phenicols. Phylogenetic analysis based on accessory genes clustered S. Legon strains separately from the S. Muenster strains. These strains were from different markets suggesting local circulation of related strains. Our study justifies consumer resistance to consumption of unripened soft cheese without further lethal heat treatment, and provides evidence that supports the Ghana Health Service recommendation for use of 3rd generation cephalosporins for the treatment of MDR NTS infections. | 2018 | 29680695 |
| 1303 | 10 | 0.9679 | Isolation and Characterization of Antimicrobial-Resistant Escherichia coli from Retail Meats from Roadside Butcheries in Uganda. Retail meats are one of the main routes for spreading antimicrobial-resistant bacteria (ARB) from livestock to humans through the food chain. In African countries, retail meats are often sold at roadside butcheries without chilling or refrigeration. Retail meats in those butcheries are suspected to be contaminated by ARB, but it was not clear. In this study, we tested for the presence of antimicrobial-resistant Escherichia coli from retail meats (n = 64) from roadside butcheries in Kampala, Uganda. The meat surfaces were swabbed and inoculated on PetriFilm SEC agar to isolate E. coli. We successfully isolated E. coli from 90.6% of these retail meat samples. We identified the phylogenetic type, antimicrobial susceptibility, and antimicrobial resistance genes prevalence between retail meat isolates (n = 89). Phylogenetic type B1 was identified from 70.8% of the retail meat isolates, suggesting that the isolates originated primarily from fecal contamination during meat processing. Tetracycline (TET)-resistant isolates with tetA and/or tetB gene(s) were the most frequently detected (28.1%), followed by ampicillin (AMP) resistance genes with bla(TEM) (15.7%,) and sulfamethoxazole-trimethoprim (SXT) resistance genes with sul2 (15.7%). No extended-spectrum beta-lactamase-producing isolates were detected. A conjugation assay showed that resistance to AMP, TET, and SXT could be simultaneously transferred to recipients. These findings suggest that antimicrobial-resistant E. coli can easily be transferred from farms to tables from retail meats obtained from roadside butcheries. | 2020 | 32551973 |
| 1382 | 11 | 0.9679 | Surveillance of antimicrobial-resistant Escherichia coli in Sheltered dogs in the Kanto Region of Japan. There is a lack of an established antimicrobial resistance (AMR) surveillance system in animal welfare centers. Therefore, the AMR prevalence in shelter dogs is rarely known. Herein, we conducted a survey in animal shelters in Chiba and Kanagawa prefectures, in the Kanto Region, Japan, to ascertain the AMR status of Escherichia coli (E. coli) prevalent in shelter dogs. E. coli was detected in the fecal samples of all 61 and 77 shelter dogs tested in Chiba and Kanagawa, respectively. The AMR was tested against 20 antibiotics. E. coli isolates derived from 16.4% and 26.0% of samples from Chiba and Kanagawa exhibited resistance to at least one antibiotic, respectively. E. coli in samples from Chiba and Kanagawa prefectures were commonly resistant to ampicillin, piperacillin, streptomycin, kanamycin, tetracycline, and nalidixic acid; that from the Kanagawa Prefecture to cefazolin, cefotaxime, aztreonam, ciprofloxacin, and levofloxacin and that from Chiba Prefecture to chloramphenicol and imipenem. Multidrug-resistant bacteria were detected in 18 dogs from both regions; β-lactamase genes (blaTEM, blaDHA-1, blaCTX-M-9 group CTX-M-14), quinolone-resistance protein genes (qnrB and qnrS), and mutations in quinolone-resistance-determining regions (gyrA and parC) were detected. These results could partially represent the AMR data in shelter dogs in the Kanto Region of Japan. | 2022 | 35031646 |
| 1322 | 12 | 0.9678 | Phenotypic and genotypic characterization of antimicrobial resistance in faecal enterococci from wild boars (Sus scrofa). The objective was to study the prevalence of antimicrobial resistance and the mechanisms implicated in faecal enterococci of wild boars in Portugal. One hundred and thirty-four enterococci (67 E. faecium, 54 E. hirae, 2 E. faecalis, 2 E. durans and 9 Enterococcus spp.) were recovered from 67 wild boars (two isolates/sample), and were further analysed. High percentages of resistance were detected for erythromycin, tetracycline, and ciprofloxacin (48.5%, 44.8%, and 17.9%, respectively), and lower values were observed for high-level-kanamycin, -streptomycin, chloramphenicol, and ampicillin resistance (9%, 6.7%, 4.5%, and 3.7%, respectively). No isolates showed vancomycin or high-level-gentamicin resistance. The erm(B), tet(M), aph(3')-IIIa, and ant(6)-I genes were demonstrated in all erythromycin-, tetracycline-, kanamycin-, and streptomycin-resistant isolates, respectively. Specific genes of Tn916/Tn1545 and Tn5397 transposons were detected in 78% and 47% of our tet(M)-positive enterococci, respectively. The tet(S) and tet(K) genes were detected in one isolate of E. faecium and E. hirae, respectively. Three E. faecium isolates showed quinupristin-dalfopristin resistance and the vat(E) gene was found in all of them showing the erm(B)-vat(E) linkage. Four E. faecium isolates showed ampicillin-resistance and all of them presented seven amino acid substitutions in PBP5 protein (461Q-->K, 470H-->Q, 485M-->A, 496N-->K, 499A-->T, 525E-->D, and 629E-->V), in relation with the reference one; a serine insertion at 466' position was found in three of the isolates. Faecal enterococci from wild boars harbour a variety of antimicrobial resistance mechanisms and could be a reservoir of antimicrobial resistance genes and resistant bacteria that could eventually be transmitted to other animals or even to humans. | 2007 | 17658226 |
| 2647 | 13 | 0.9678 | Antibiotic Susceptibility and Virulence Factors in Escherichia coli from Sympatric Wildlife of the Apuan Alps Regional Park (Tuscany, Italy). Today a growing number of studies are focusing on antibiotic resistance in wildlife. This is due to the potential role of wild animals as reservoirs and spreaders of pathogenic and resistant bacteria. This study focused on isolating and identifying Escherichia coli from the feces of wild animals living in the Apuan Alps Regional Park (Tuscany, Italy) and evaluating some of their antibiotic resistance and pathogenicity traits. Eighty-five fecal samples from different species were studied. Seventy-one E. coli were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry analysis, subjected to antibiograms and polymerase chain reaction for the detection of antibiotic resistance genes and pathogenicity factors. The highest resistance rates were found against cephalothin (39.4%) and ampicillin (33.8%), followed by amoxicillin/clavulanic acid (15.5%), streptomycin (12.7%), and tetracycline (5.6%). Regarding resistance genes, 39.4% of the isolates were negative for all tested genes. The remaining isolates were positive for bla(CMY)(-2), sul2, strA-strB and aadA1, tet(B), and tet(A), encoding resistance to beta-lactams, trimethoprim/sulfamethoxazole, streptomycin, and tetracycline, respectively. With regard to virulence factors, 63.4% of the isolates were negative for all genes; 21.1% carried astA alone, which is associated with different pathotypes, 9.9% carried both escV and eaeA (aEPEC); single isolates (1.4%) harbored escV (aEPEC), escV associated with astA and eaeA (aEPEC), astA with stx2 and hlyA (EHEC) or astA and stx1, stx2, and hlyA (EHEC). These results show that wildlife from nonanthropized environments can be a reservoir for antibiotic-resistant microorganisms and suggest the need for a deeper knowledge on their origin and diffusion mechanisms through different ecological niches. | 2019 | 30676273 |
| 1301 | 14 | 0.9677 | Phenotypic and Genotypic Assessment of Antibiotic Resistance of Staphylococcus aureus Bacteria Isolated from Retail Meat. BACKGROUND: Resistant Staphylococcus aureus (S. aureus) bacteria are determined to be one of the main causes of foodborne diseases. PURPOSE: This survey was done to assess the genotypic and phenotypic profiles of antibiotic resistance of S. aureus bacteria isolated from retail meat. METHODS: Four-hundred and eighty-five retail meat samples were collected and examined. S. aureus bacteria were identified using culture and biochemical tests. The phenotypic profile of antibiotic resistance was examined using the disk diffusion method. The genotypic pattern of antibiotic resistance was determined using the polymerase chain reaction. RESULTS: Forty-eight out of 485 (9.89%) raw retail meat samples were contaminated with S. aureus. Raw retail buffalo meat (16%) had the highest incidence of S. aureus, while raw camel meat (4%) had the lowest. S. aureus bacteria exhibited the uppermost incidence of resistance toward tetracycline (79.16%), penicillin (72.91%), gentamicin (60.41%), and doxycycline (41.666%). The incidence of resistance toward chloramphenicol (8.33%), levofloxacin (22.91%), rifampin (22.91%), and azithromycin (25%) was lower than other examined antibiotics. The most routinely detected antibiotic resistance genes were blaZ (58.33%), tetK (52.08%), aacA-D (33.33%), and ermA (27.08%). Cat1 (4.16%), rpoB (10.41%), msrA (12.50%), grlA (12.50%), linA (14.58%), and dfrA1 (16.66%) had the lower incidence rate. CONCLUSION: Raw meat of animals may be sources of resistant S. aureus which pose a hygienic threat about the consumption of raw meat. Nevertheless, further investigations are essential to understand supplementary epidemiological features of S. aureus in retail meat. | 2020 | 32440171 |
| 1323 | 15 | 0.9677 | Detection of antibiotic resistant enterococci and Escherichia coli in free range Iberian Lynx (Lynx pardinus). Thirty fecal samples from wild specimens of Iberian lynx were collected and analyzed for Enterococcus spp. (27 isolates) and Escherichia coli (18 isolates) recovery. The 45 isolates obtained were tested for antimicrobial resistance, molecular mechanisms of resistance, and presence of virulence genes. Among the enterococci, Enterococcus faecium and Enterococcus hirae were the most prevalent species (11 isolates each), followed by Enterococcus faecalis (5 isolates). High percentages of resistance to tetracycline and erythromycin (33% and 30%, respectively) were detected among enterococcal isolates. The tet(M) and/or tet(L), erm(B), aac(6')-Ie-aph(2″)-Ia, ant(6)-Ia, or aph(3')-IIIa genes were detected among resistant enterococci. Virulence genes were detected in one E. faecalis isolate (cpd, cylB, and cylL) and one E. hirae isolate (cylL). High percentages of resistance were detected in E. coli isolates to tetracycline (33%), streptomycin (28%), nalidixic acid (28%), and sulfamethoxazole-trimethoprim (SXT, 22%). Additionally, the blaTEM, tet(A), aadA, cmlA, and different combinations of sul genes were detected among most ampicillin, tetracycline, streptomycin, chloramphenicol and SXT-resistant isolates, respectively. Two isolates contained a class 1 integron with the gene cassette arrays dfrA1 + aadA1 and dfrA12 + aadA2. The E. coli isolates were ascribed to phylo-groups A (n=5); B1 (n=4); B2 (n=6), and D (n=3), with the virulence gene fimA present in all E. coli isolates. This study found resistance genes in wild specimens of Iberian lynx. Thus, it is important to notice that multiresistant bacteria have reached species as rare and completely non-synanthropic as the Iberian lynx. Furthermore, the susceptibility of this endangered species to bacterial infection may be affected by the presence of these virulence and resistance genes. | 2013 | 23588135 |
| 1316 | 16 | 0.9675 | Virulence factors and antimicrobial resistance in Escherichia coli strains isolated from hen egg shells. Eggs may contain extraintestinal pathogenic (ExPEC) and diarrheogenic (DEC) Escherichia coli which in addition may carry antibiotic resistance. The wide use of biocides and disinfectants in the food industry may induce biocide tolerance in bacteria. The aim of the present study was to evaluate biocide tolerance and antibiotic resistance in E. coli from hen egg shells. A total of 27 isolates obtained from a screening of 180 eggs were studied. Seven isolates carried both eae and bfpA genes of typical enteropathogenic E. coli (EPEC) strains, while 14 isolates only carried eae associated with atypical EPEC strains. Shiga toxin genes stx and stx2 were detected in four isolates. Heat-stable and heat-labile enterotoxin genes as well as aggR were also detected. Several isolates had minimum inhibitory concentrations (MICs) that were higher than the wild-type for the biocide hexadecylpyridinium chloride (HDP, 18.52%) or the commercial disinfectant P3 oxonia (OX, 14.81%). Antibiotic resistance was detected for ampicillin (37.03%), streptomycin (37.03%), tetracycline (37.03%), chloramphenicol (11.11%), nalidixic acid (18.51%) and trimethoprim-sulfamethoxazole (14.81%). Eight isolates (29.63%) were biocide tolerant and antibiotic resistant. Efflux pump genes detected included acrB (96.29%), mdfA (85.18%) and oxqA (37.03%), in addition to quaternary ammonium compound (QAC) resistance genes qacA/B (11.11%) and qacE (7.40%). Antibiotic resistance genes detected included bla(CTX-M-2) (22.22%), bla(TEM) (3.70%), bla(PSE) (3.70%), tet(A) (29.63%), tet(B) (29.63%), tet(C) (7.40%), tet(E) (11.11%), aac(6')-Ib (3.70%), sul1 (14.81%), dfrA12 (3.70%) and dfrA15 (3.70%). Most isolates (96.30%) carried more than one genetic determinant of resistance. The most frequent combinations were efflux pump components acrB and mdfA with tetracycline resistance genes (33.33% of isolates). Isolates carrying QAC resistance genes also carried between 4 and 8 of the additional antimicrobial resistance genes investigated. Regardless of biocide tolerance and antibiotic resistance, all isolates were sensitive to carvacrol (0.25%), thymol (0.125%) and trisodium phosphate (1 to 1.5%), but they exhibited a heterogeneous response to sodium lactate and lysozyme-EDTA combinations that apparently were not related with antibiotic resistance. Results from the study reveal not only a low incidence of biocide tolerance but also the presence of multiple resistance strains carrying multiple genetic determinants of resistance. | 2016 | 27607065 |
| 1227 | 17 | 0.9675 | Antibiotic resistance among coliform bacteria isolated from carcasses of commercially slaughtered chickens. A total of 322 coliform bacteria Escherichia coli, Enterobacter spp., Citrobacter spp., Klebsiella spp. and Serratia spp., were isolated from 50 carcasses of commercially slaughtered chickens. Their resistance to ampicillin, tetracycline, gentamicin, chloramphenicol, cephalotine, cotrimoxazole, nalidixic acid and nitrofurantoin, were determined. The most commonly found resistance was to tetracycline followed by cephalotine, cotrimoxazole and nalidixic acid. A large percentage of E. coli (41%) and Klebsiella spp. (38%) showed multiple antibiotic resistance. | 1990 | 2282290 |
| 2373 | 18 | 0.9675 | Antimicrobial Resistance Profiles, Virulence Determinants, and Biofilm Formation in Enterococci Isolated from Rhesus Macaques (Macaca mulatta): A Potential Threat for Wildlife in Bangladesh? Enterococci are commensal bacteria that inhabit the digestive tracts of animals and humans. The transmission of antibiotic-resistant genes through human-animal contact poses a potential public health risk worldwide, as zoonoses from wildlife reservoirs can occur on every continent. The purpose of this study was to detect Enterococcus spp. in rhesus macaques (Macaca mulatta) and to investigate their resistance patterns, virulence profiles, and biofilm-forming ability. Conventional screening of rectal swabs (n = 67) from macaques was followed by polymerase chain reaction (PCR). The biofilm-forming enterococci were determined using the Congo red agar plate assay. Using the disk diffusion test (DDT), antibiogram profiles were determined, followed by resistance and virulence genes identification by PCR. PCR for bacterial species confirmation revealed that 65.7% (44/67) and 22.4% (15/67) of the samples tested positive for E. faecalis and E. faecium, respectively. All the isolated enterococci were biofilm formers. In the DDT, enterococcal isolates exhibited high to moderate resistance to penicillin, rifampin, ampicillin, erythromycin, vancomycin, and linezolid. In the PCR assays, the resistance gene bla(TEM) was detected in 61.4% (27/44) of E. faecalis and 60% (9/15) of E. faecium isolates. Interestingly, 88.63 % (39/44) of E. faecalis and 100% (15/15) of E. faecium isolates were phenotypically multidrug-resistant. Virulence genes (agg, fsrA, fsrB, fsrC, gelE, sprE, pil, and ace) were more frequent in E. faecalis compared to E. faecium; however, isolates of both Enterococcus spp. were found negative for the cyl gene. As far as we know, the present study has detected, for the first time in Bangladesh, the presence of virulence genes in MDR biofilm-forming enterococci isolated from rhesus macaques. The findings of this study suggest employing epidemiological surveillance along with the one-health approach to monitor these pathogens in wild animals in Bangladesh, which will aid in preventing their potential transmission to humans. | 2023 | 37508046 |
| 1299 | 19 | 0.9675 | Prevalence, Drug Resistance, and Virulence Genes of Potential Pathogenic Bacteria in Pasteurized Milk of Chinese Fresh Milk Bar. Fresh Milk Bar (FMB), an emerging dairy retail franchise, is used to instantly produce and sell pasteurized milk and other dairy products in China. However, the quality and safety of pasteurized milk in FMB have received little attention. The objective of this study was to investigate the prevalence, antimicrobial resistance, and virulence genes of Escherichia coli, Staphylococcus aureus, and Streptococcus in 205 pasteurized milk samples collected from FMBs in China. Four (2.0%) isolates of E. coli, seven (3.4%) isolates of S. aureus, and three (1.5%) isolates of Streptococcus agalactiae were isolated and identified. The E. coli isolates were resistant to amikacin (100%), streptomycin (50%), and tetracycline (50%). Their detected resistance genes include aac(3)-III (75%), blaTEM (25%), aadA (25%), aac(3)-II (25%), catI (25%), and qnrB (25%). The S. aureus isolates were mainly resistant to penicillin G (71.4%), trimethoprim-sulfamethoxazole (71.4%), kanamycin (57.1%), gentamicin (57.1%), amikacin (57.1%), and clindamycin (57.1%). blaZ (42.9%), mecA (28.6%), ermB (14.3%), and ermC (14.3%) were detected as their resistance genes. The Streptococcus strains were mainly resistant to tetracycline (66.7%) and contained the resistance genes pbp2b (33.3%) and tetM (33.3%). The virulence genes eae and stx2 were only found in one E. coli strain (25%), sec was detected in two S. aureus strains (28.6%), and bca was detected in one S. agalactiae strain (33.3%). The results of this study indicate that bacteria with drug resistance and virulence genes isolated from the pasteurized milk of FMB are a potential risk to consumers' health. | 2021 | 34129676 |