# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 2685 | 0 | 1.0000 | Prevalence and genomic characterization of the Bacillus cereus group strains contamination in food products in Southern China. The Bacillus cereus group, as one of the important opportunistic foodborne pathogens, is considered a risk to public health due to foodborne diseases and an important cause of economic losses to food industries. This study aimed to gain essential information on the prevalence, phenotype, and genotype of B. cereus group strains isolated from various food products in China. A total of 890 strains of B. cereus group bacteria from 1181 food samples from 2020 to 2023 were identified using the standardized detection method. These strains were found to be prevalent in various food types, with the highest contamination rates observed in cereal flour (55.8 %) and wheat/rice noodles (45.7 %). The tested strains exhibited high resistance rates against penicillin (98.5 %) and ampicillin (98.9 %). Strains isolated from cereal flour had the highest rate of meropenem resistance (7.8 %), while strains from sausages were most resistant to vancomycin (16.8 %). A total of 234 out of the 891 B. cereus group strains were randomly selected for WGS analysis, 18.4 % of which displayed multidrug resistance. The species identification by WGS analysis revealed the presence of 10 distinct species within the B. cereus group, with B. cereus species being the most prevalent. The highest level of species diversity was observed in sausages. Notably, B. anthracis strains lacking the anthrax toxin genes were detected in flour-based food products and sausages. A total of 20 antibiotic resistance genes have been identified, with β-lactam resistance genes (bla1, bla2, BcI, BcII, and bla(TEM-116)) being the most common. The B. tropicus strains exhibit the highest average number of virulence genes (23.4). The diarrheal virulence genes nheABC, hblACD, and cytK were found in numerous strains. Only 4 of the 234 (1.7 %) sequenced strains contain the ces gene cluster linked to emetic symptoms. These data offer valuable insights for public health policymakers on addressing foodborne B. cereus group infections and ensuring food safety. | 2024 | 38354793 |
| 2677 | 1 | 0.9998 | Detection of Staphylococcus Isolates and Their Antimicrobial Resistance Profiles and Virulence Genes from Subclinical Mastitis Cattle Milk Using MALDI-TOF MS, PCR and Sequencing in Free State Province, South Africa. Staphylococcus species are amongst the bacteria that cause bovine mastitis worldwide, whereby they produce a wide range of protein toxins, virulence factors, and antimicrobial-resistant properties which are enhancing the pathogenicity of these organisms. This study aimed to detect Staphylococcus spp. from the milk of cattle with subclinical mastitis using MALDI-TOF MS and 16S rRNA PCR as well as screening for antimicrobial resistance (AMR) and virulence genes. Our results uncovered that from 166 sampled cows, only 33.13% had subclinical mastitis after initial screening, while the quarter-level prevalence was 54%. Of the 50 cultured bacterial isolates, MALDI-TOF MS and 16S rRNA PCR assay and sequencing identified S. aureus as the dominant bacteria by 76%. Furthermore, an AMR susceptibility test showed that 86% of the isolates were resistant to penicillin, followed by ciprofloxacin (80%) and cefoxitin (52%). Antimicrobial resistance and virulence genes showed that 16% of the isolates carried the mecA gene, while 52% of the isolates carried the Lg G-binding region gene, followed by coa (42%), spa (40%), hla (38%), and hlb (38%), whereas sea and bap genes were detected in 10% and 2% of the isolates, respectively. The occurrence of virulence factors and antimicrobial resistance profiles highlights the need for appropriate strategies to control the spread of these pathogens. | 2024 | 38200885 |
| 2399 | 2 | 0.9998 | Ready-to-eat dairy products as a source of multidrug-resistant Enterococcus strains: Phenotypic and genotypic characteristics. The enterococci are ubiquitous bacteria able to colonize the human and animal gastrointestinal tracts and fresh and fermented food products. Their highly plastic genome allows Enterococcus spp. to gain resistance to multiple antibiotics, making infections with these organisms difficult to treat. Food-borne enterococci could be carriers of antibiotic resistance determinants. The goal of this work was to study the characteristics of Enterococcus spp. in fermented milk products from Poland and their antibiotic resistance gene profiles. A total of 189 strains were isolated from 182 dairy products out of 320 samples tested. The predominant species were Enterococcus faecium (53.4%) and Enterococcus faecalis (34.4%). Isolates were resistant to streptomycin (29.1%), erythromycin (14.3%), tetracycline (11.6%), rifampicin (8.7%), and tigecycline (8.1%). We also detected 2 vancomycin-resistant and 3 linezolid-resistant strains; however, no vanA or vanB genes were identified. A total of 57 high-level aminoglycoside resistance strains (30.2%) were identified, most of which have the ant(6')-Ia gene, followed by the aac(6')-Ie-aph(2″)-Ia and aph(3″)-IIIa genes. Resistance to tetracycline was most often conferred by tetM and tetL genes. Macrolide resistance was most frequently encoded by ermB and ermA genes. Conjugative mobile genetic element (transposon Tn916-Tn1545) was identified in 15.3% of the strains, including 96.3% of strains harboring the tetM gene. This study found that enterococci are widely present in retail ready-to-eat dairy products in Poland. Many isolated strains are antibiotic resistant and carry transferable resistance genes, which represent a potential source of transmission of multidrug-resistant bacteria to humans. | 2020 | 32197843 |
| 2670 | 3 | 0.9998 | Molecular characterisation and antimicrobial resistance of Streptococcus agalactiae isolates from dairy farms in China. INTRODUCTION: Streptococcus agalactiae (S. agalactiae) is a pathogen causing bovine mastitis that results in considerable economic losses in the livestock sector. To understand the distribution and drug resistance characteristics of S. agalactiae from dairy cow mastitis cases in China, multilocus sequence typing (MLST) was carried out and the serotypes and drug resistance characteristics of the bacteria in the region were analysed. MATERIAL AND METHODS: A total of 21 strains of bovine S. agalactiae were characterised based on MLST, molecular serotyping, antimicrobial susceptibility testing, and the presence of drug resistance genes. RESULTS: The serotypes were mainly Ia and II, accounting for 47.6% and 42.9% of all serotypes, respectively. Five sequence types (STs) were identified through MLST. The ST103 and ST1878 strains were predominant, with rates of 52.4% and 28.6%, respectively. The latter is a novel, previously uncharacterised sequence type. More than 90% of S. agalactiae strains were susceptible to penicillin, oxacillin, cephalothin, ceftiofur, gentamicin, florfenicol and sulfamethoxazole. The bacteria showed high resistance to tetracycline (85.7%), clindamycin (52.1%) and erythromycin (47.6%). Resistant genes were detected by PCR, the result of which showed that 47.6%, 33.3% and 38.1% of isolates carried the tet(M), tet(O) and erm(B) genes, respectively. CONCLUSION: The results of this study indicate that S. agalactiae show a high level of antimicrobial resistance. It is necessary to monitor the pathogens of mastitis to prevent the transmission of these bacteria. | 2023 | 38143824 |
| 2671 | 4 | 0.9998 | Toxinotyping and molecular characterization of antimicrobial resistance in Clostridium perfringens isolated from different sources of livestock and poultry. The present study was designed to understand the presence of antimicrobial resistance among the prevalent toxinotypes of Clostridium perfringens recovered from different animals of Tamil Nadu, India. A total of 75 (10.76%) C. perfringens were isolated from 697 multi-species fecal and intestinal content samples. C. perfringens type A (90.67%), type C (2.67%), type D (4%) and type F (2.67%) were recovered. Maximum number of isolates were recovered from dog (n = 20, 24.10%) followed by chicken (n = 19, 5.88%). Recovered isolates were resistant to gentamicin (44.00%), erythromycin (40.00%), bacitracin (40.00%), and tetracycline (26.67%), phenotypically and most of the isolates were found to be resistant to multiple antimicrobials. Genotypic characterization revealed that tetracycline (41.33%), erythromycin (34.66%) and bacitracin (17.33%) resistant genes were present individually or in combination among the isolates. Combined results of phenotypic and genotypic characterization showed the highest percentage of erythromycin resistance (26.66%) among the isolates. None of the isolates showed amplification for lincomycin resistance genes. The correlation matrix analysis of genotypic resistance showed a weak positive relationship between the tetracycline and bacitracin resistance while a weak negative relationship between the tetracycline and erythromycin resistance. The present study thus reports the presence of multiple-resistance genes among C. perfringens isolates that may be involved in the dissemination of resistance to other bacteria present across species. Further insights into the genome can help to understand the mechanism involved in gene transfer so that measures can be taken to prevent the AMR spread. | 2021 | 33220406 |
| 2718 | 5 | 0.9997 | Virulence-Associated Genes and Antimicrobial Resistance of Aeromonas hydrophila Isolates from Animal, Food, and Human Sources in Brazil. Aeromonads are natural inhabitants of aquatic environments and may be associated with various human or animal diseases. Its pathogenicity is complex and multifactorial and is associated with many virulence factors. In this study, 110 selected Aeromonas hydrophila isolates isolated from food, animals, and human clinical material from 2010 to 2015 were analyzed. Antimicrobial susceptibility testing was performed by the disk diffusion method, and polymerase chain reaction was conducted to investigate the virulence genes hemolysin (hlyA), cytotoxic enterotoxin (act), heat-labile cytotonic enterotoxin (alt), aerolysin (aerA), and DNase-nuclease (exu). At least 92.7% of the isolates had one of the investigated virulence genes. Twenty different virulence profiles among the isolates were recognized, and the five investigated virulence genes were observed in four isolates. Human source isolates showed greater diversity than food and animal sources. Antimicrobial resistance was observed in 46.4% of the isolates, and multidrug resistance was detected in 3.6% of the isolates. Among the 120 isolates, 45% were resistant to cefoxitin; 23.5% to nalidixic acid; 16.6% to tetracycline; 13.7% to cefotaxime and imipenem; 11.8% to ceftazidime; 5.9% to amikacin, gentamicin, and sulfamethoxazole-trimethoprim; and 3.9% to ciprofloxacin and nitrofurantoin. Overall, the findings of our study indicated the presence of virulence genes and that antimicrobial resistance in A. hydrophila isolates in this study is compatible with potentially pathogenic bacteria. This information will allow us to recognize the potential risk through circulating isolates in animal health and public health and the spread through the food chain offering subsidies for appropriate sanitary actions. | 2020 | 32461959 |
| 2967 | 6 | 0.9997 | Antibiotic susceptibility and prevalence of foodborne pathogens in poultry meat in Romania. INTRODUCTION: The occurrence of pathogenic strains in poultry meat is of growing concern in Romania. Another problem found on a global level is the continuous increase of antimicrobial resistance in bacteria isolated from food. This study aimed to evaluate the prevalence of pathogenic bacteria in poultry carcasses obtained in Romania in 2012-2013 and to reveal the most prevalent patterns of antimicrobial resistance in the isolated strains. METHODOLOGY: A total of 144 broiler chicken carcasses were evaluated according to classical microbiological methods. The DNA was extracted from the bacterial colonies and the resistance genes were identified by PCR. RESULTS: In 2012, 47.2% of the samples revealed at least one of the following bacteria: Campylobacter jejuni (9.72%; n = 7), Salmonella enterica serotype Enteritidis (4.17%; n = 3), Listeria monocytogenes (15.28%; n = 11), and Escherichia coli (16.67%; n = 12). In 2013, the number of positive samples of pathogenic bacteria decreased, although Campylobacter jejuni was isolated in a higher percentage (20.8% vs. 9.72%). The percentage of multidrug-resistant (MDR) bacteria was high (23%); the most prevalent pattern included resistance to tetracycline, sulfonamides, and quinolones/fluoroquinolones. All the resistant Salmonella and E. coli strains were tested for the presence of characteristic resistance genes (Kn, bla(TEM), tetA, tetB, tetG, DfrIa, aadA1a, Sul) and revealed that these isolates represent an important reservoir in the spread of this phenomenon. CONCLUSIONS: Our findings suggest that Romania urgently needs an integrated surveillance system within the entire chain, for drug-resistant pathogens isolated from poultry meat. | 2015 | 25596569 |
| 2693 | 7 | 0.9997 | Prevalence, Antimicrobial Resistance and Toxin-Encoding Genes of Clostridioides difficile from Environmental Sources Contaminated by Feces. Clostridioides difficile (C. difficile) is the most common pathogen causing antibiotic-associated intestinal diseases in humans and some animal species, but it can also be present in various environments outside hospitals. Thus, the objective of this study was to investigate the presence and the characteristics of toxin-encoding genes and antimicrobial resistance of C. difficile isolates from different environmental sources. C. difficile was found in 32 out of 81 samples (39.50%) after selective enrichment of spore-forming bacteria and in 45 samples (55.56%) using a TaqMan-based qPCR assay. A total of 169 C. difficile isolates were recovered from those 32 C. difficile-positive environmental samples. The majority of environmental C. difficile isolates were toxigenic, with many (88.75%) positive for tcdA and tcdB. Seventy-four isolates (43.78%) were positive for binary toxins, cdtA and cdtB, and 19 isolates were non-toxigenic. All the environmental C. difficile isolates were susceptible to vancomycin and metronidazole, and most isolates were resistant to ciprofloxacin (66.86%) and clindamycin (46.15%), followed by moxifloxacin (13.02%) and tetracycline (4.73%). Seventy-five isolates (44.38%) showed resistance to at least two of the tested antimicrobials. C. difficile strains are commonly present in various environmental sources contaminated by feces and could be a potential source of community-associated C. difficile infections. | 2023 | 36671363 |
| 2700 | 8 | 0.9997 | Prevalence of Salmonella Typhimurium and Salmonella Enteritidis isolated from poultry meat: virulence and antimicrobial-resistant genes. Salmonellosis, a zoonotic disease, is one of the leading causes of foodborne illness worldwide. It is responsible for most infections caused by consumption of contaminated food. In recent years, a significant increase in the resistance of these bacteria to common antibiotics has been observed, posing a serious threat to global public health. The aim of this study was to investigate the prevalence of virulent antibiotic-resistant Salmonella spp. strains in Iranian poultry markets. A total of 440 chicken meat samples were randomly selected from meat supply and distribution facilities in Shahrekord and tested for bacteriological contamination. After culturing and isolating the strains, identification was performed using the classical bacteriological method and PCR. To determine antibiotic resistance, a disc diffusion test was performed according to the recommendations of the French Society of Microbiology. PCR was used to detect resistance and virulence genes. Only 9% of the samples were positive for Salmonella. These were Salmonella typhimurium isolates. All Salmonella typhimurium serotypes tested positive for the rfbJ, fljB, invA and fliC genes. Resistance to TET, cotrimoxazole, NA, NIT, piperacillin/tazobactam and other antibiotics was found in 26 (72.2%), 24 (66.7%), 22 (61.1%) and 21 (58.3%) isolates, respectively. The sul1, sul2 and sul3 genes were present in 20, 12 and 4 of 24 cotrimoxazole-resistant bacteria, respectively. Chloramphenicol resistance was found in six isolates, but more isolates tested positive for the floR and cat two genes. In contrast, 2 (33%) of the cat three genes, 3 (50%) of the cmlA genes and 2 (34%) of the cmlB genes were all positive. The results of this investigation showed that Salmonella typhimurium is the most common serotype of the bacterium. This means that most of the antibiotics commonly used in the livestock and poultry industries are ineffective against most Salmonella isolates, which is important for public health. | 2023 | 37322421 |
| 2692 | 9 | 0.9997 | Tetracycline Resistance Genes in Campylobacter jejuni and C. coli Isolated From Poultry Carcasses. BACKGROUND: Campylobacter is one of the leading bacterial species causing foodborne illnesses in humans. Antimicrobial agents have been extensively used for treatment of Campylobacter infections; but in the recent years, both animal and human isolates of this bacterium have shown resistance to several antibiotics such as tetracycline. OBJECTIVES: The aim of this study was to investigate the presence of genetic determinants of tetracycline resistance in Campylobacter spp. recovered from poultry carcasses in Shiraz, Iran. MATERIALS AND METHODS: Eighty-three thermophilic Campylobacter spp. Isolates were first identified based on multiplex polymerase chain reaction (PCR) and then screened for presence of tetracycline resistance genes (tet (A), tet (B), tet (O) and te (S)) by PCR. RESULTS: The overall prevalence of Campylobacter jejuni and C. coli among the examined isolates was 51.8% and 48.2%, respectively. Tetracycline resistance genes of tet (B) and tet (S) were not seen among these Campylobacter spp. Isolates, whereas the most common tet gene identified was tet (O), found in 83.1% (69/83) of all the isolates. The tet (O) gene sequence comparison between C. jejuni and C. coli showed 100% similarity and these sequences (JX853721and JX853722) were also identical to the homologous sequences of other strains of Campylobacter spp. existing in the GenBank databases. In addition, tet (A) was found in 18% (15/83) of Campylobacter spp. isolates. To our knowledge, this represents the first report of tet (A) in Campylobacter spp. There was 100% homology between the sequences of tet (A) from this study (JX891463 and JX891464) and the tet (A) sequences mentioned for other bacteria in the GenBank databases. CONCLUSIONS: The high prevalence of tet (O) resistance gene along with new detection of tet (A) resistance gene in Campylobacter spp. isolated from poultry carcasses revealed an extensive tetracycline resistance among Campylobacter isolates from poultry in Iran. It emphasized the need for cautious use of tetracycline in poultry production to decrease the extension of tetracycline-resistant Campylobacter spp. | 2014 | 25485062 |
| 2385 | 10 | 0.9997 | Molecular characterization of multi-drug-resistant Staphylococcus aureus in mastitis bovine milk from a dairy farm in Anhui, China. Mastitis is an economically important disease in the dairy industry, which is caused by various infectious pathogens. There is limited information known about the situation of drug resistance and virulence factors of Staphylococcus aureus (S. aureus) in mastitis bovine milk in Anhui. Therefore, a total of 125 fresh milk samples from clinically mastitis-positive bovine animals were collected. The bacteria pathogens were identified via bacterial culture, Gram staining, biochemical analysis, DNA extraction, 16s rRNA amplification, and phylogenetic analysis. Drug resistance analyses were performed through drug-resistant genes and virulence genes amplification. Results showed that a total of 24.8% (31/125) bacterial isolates were isolated and identified as S. aureus by Gram straining, biochemical reactions, and 16 s rRNA genes blasting. Multiple sequence alignment analysis found that the current isolates were highly similar (96.9-100.0%) to previous isolates. Phylogenetic analysis demonstrated that S. aureus was similar with MK809241.1 isolated from food in China and wCP030426.1 isolated from a person in the United States. The bacterial isolates were detected resistant to 11 antibiotics, such as Penicillin G, SXT, Ciprofloxacin, Norfloxacin, Polymyxin B, Levofloxacin, Chloramphenicol, Clindamycin, Clarithromycin, Erythromycin, and Spectinomycin. Drug-resistant genes of blaZ, ermC, rpoB, and ant (4')-la were successfully amplified. Virulence genes of hla, nuc, clfa, and eta were found in S. aureus bacteria. The current study isolated S. aureus from milk samples and revealed its drug-resistant situation, drug-resistant genes, and virulence genes. Hence, regular monitoring of S. aureus in milk samples from dairy cows may contribute to the prevention and treatment of public health concerns causing bacteria in this region. | 2022 | 36072389 |
| 2386 | 11 | 0.9997 | Molecular typing and prevalence of antibiotic resistance and virulence genes in Streptococcus agalactiae isolated from Chinese dairy cows with clinical mastitis. Bovine mastitis is a common disease occurring in dairy farms and can be caused by more than 150 species of pathogenic bacteria. One of the most common causative organisms is Streptococcus agalactiae, which is also potentially harmful to humans and aquatic animals. At present, research on S. agalactiae in China is mostly concentrated in the northern region, with limited research in the southeastern and southwestern regions. In this study, a total of 313 clinical mastitis samples from large-scale dairy farms in five regions of Sichuan were collected for isolation of S. agalactiae. The epidemiological distribution of S. agalactiae was inferred by serotyping isolates with multiplex polymerase chain reaction. Susceptibility testing and drug resistance genes were detected to guide the clinical use of antibiotics. Virulence genes were also detected to deduce the pathogenicity of S. agalactiae in Sichuan Province. One hundred and five strains of S. agalactiae (33.6%) were isolated according to phenotypic features, biochemical characteristics, and 16S rRNA sequencing. Serotype multiplex polymerase chain reaction analysis showed that all isolates were of type Ia. The isolates were up to 100% sensitive to aminoglycosides (kanamycin, gentamicin, neomycin, and tobramycin), and the resistance rate to β-lactams (penicillin, amoxicillin, ceftazidime, and piperacillin) was up to 98.1%. The TEM gene (β-lactam-resistant) was detected in all isolates, which was in accordance with a drug-resistant phenotype. Analysis of virulence genes showed that all isolates harbored the cfb, cylE, fbsA, fbsB, hylB, and α-enolase genes and none harbored bac or lmb. These data could aid in the prevention and control of mastitis and improve our understanding of epidemiological trends in dairy cows infected with S. agalactiae in Sichuan Province. | 2022 | 35522690 |
| 2398 | 12 | 0.9997 | Antimicrobial-Resistant Enterococcus spp. in Wild Avifauna from Central Italy. Bacteria of the genus Enterococcus are opportunistic pathogens, part of the normal intestinal microflora of animals, able to acquire and transfer antimicrobial resistance genes. The aim of this study was to evaluate the possible role of wild avifauna as a source of antimicrobial-resistant enterococci. To assess this purpose, 103 Enterococcus spp. strains were isolated from the feces of wild birds of different species; they were tested for antimicrobial resistance against 21 molecules, vancomycin resistance, and high-level aminoglycosides resistance (HLAR). Furthermore, genes responsible for vancomycin, tetracycline, and HLAR were searched. E. faecium was the most frequently detected species (60.20% of isolates), followed by E. faecalis (34.95% of isolates). Overall, 99.02% of the isolated enterococci were classified as multidrug-resistant, with 19.41% extensively drug-resistant, and 2.91% possible pan drug-resistant strains. Most of the isolates were susceptible to amoxicillin/clavulanic acid (77.67%) and ampicillin (75.73%), with only 5.83% of isolates showing an ampicillin MIC ≥ 64 mg/L. HLAR was detected in 35.92% of isolates, mainly associated with the genes ant(6)-Ia and aac(6')-Ie-aph(2″)-Ia. Few strains (4.85%) were resistant to vancomycin, and the genes vanA and vanB were not detected. A percentage of 54.37% of isolates showed resistance to tetracycline; tet(M) was the most frequently detected gene in these strains. Wild birds may contribute to the spreading of antimicrobial-resistant enterococci, which can affect other animals and humans. Constant monitoring is essential to face up to the evolving antimicrobial resistance issue, and monitoring programs should include wild avifauna, too. | 2022 | 35884106 |
| 2903 | 13 | 0.9997 | Soil Bacteria in Urban Community Gardens Have the Potential to Disseminate Antimicrobial Resistance Through Horizontal Gene Transfer. Fifteen soil and 45 vegetable samples from Detroit community gardens were analyzed for potential antimicrobial resistance contamination. Soil bacteria were isolated and tested by antimicrobial susceptibility profiling, horizontal gene transfer, and whole-genome sequencing. High-throughput 16S rRNA sequencing analysis was conducted on collected soil samples to determine the total bacterial composition. Of 226 bacterial isolates recovered, 54 were from soil and 172 from vegetables. A high minimal inhibitory concentration (MIC) was defined as the MIC greater than or equal to the resistance breakpoint of Escherichia coli for Gram-negative bacteria or Staphylococcus aureus for Gram-positive bacteria. The high MIC was observed in 63.4 and 69.8% of Gram-negative isolates from soil and vegetables, respectively, against amoxicillin/clavulanic acid, as well as 97.5 and 82.7% against ampicillin, 97.6 and 90.7% against ceftriaxone, 85.4 and 81.3% against cefoxitin, 65.8 and 70.5% against chloramphenicol, and 80.5 and 59.7% against ciprofloxacin. All Gram-positive bacteria showed a high MIC to gentamicin, kanamycin, and penicillin. Forty of 57 isolates carrying tetM (70.2%) successfully transferred tetracycline resistance to a susceptible recipient via conjugation. Whole-genome sequencing analysis identified a wide array of antimicrobial resistance genes (ARGs), including those encoding AdeIJK, Mex, and SmeDEF efflux pumps, suggesting a high potential of the isolates to become antimicrobial resistant, despite some inconsistency between the gene profile and the resistance phenotype. In conclusion, soil bacteria in urban community gardens can serve as a reservoir of antimicrobial resistance with the potential to transfer to clinically important pathogens, resulting in food safety and public health concerns. | 2021 | 34887843 |
| 5601 | 14 | 0.9997 | Presence of Staphylococcus spp. carriers of the mecA gene in the nasal cavity of piglets in the nursery phase. The presence of Staphylococcus spp. resistant to methicillin in the nasal cavity of swine has been previously reported. Considering the possible occurrence of bacterial resistance and presence of resistance genes in intensive swine breeding and the known transmissibility and dispersion potential of such genes, this study aimed to investigate the prevalence of resistance to different antibiotics and the presence of the mecA resistance gene in Staphylococcus spp. from piglets recently housed in a nursery. For this, 60 nasal swabs were collected from piglets at the time of their housing in the nursery, and then Staphylococcus spp. were isolated and identified in coagulase-positive (CoPS) and coagulase-negative (CoNS) isolates. These isolates were subjected to the disk-diffusion test to evaluate the bacterial resistance profile and then subjected to molecular identification of Staphylococcus aureus and analyses of the mecA gene through polymerase chain reaction. Of the 60 samples collected, 60 Staphylococcus spp. were isolated, of which 38 (63.33%) were classified as CoNS and 22 (36.67%) as CoPS. Of these, ten (45.45%) were identified as Staphylococcus aureus. The resistance profile of these isolates showed high resistance to different antibiotics, with 100% of the isolates resistant to chloramphenicol, clindamycin, and erythromycin, 98.33% resistant to doxycycline, 95% resistant to oxacillin, and 85% resistant to cefoxitin. Regarding the mecA gene, 27 (45%) samples were positive for the presence of this gene, and three (11.11%) were phenotypically sensitive to oxacillin and cefoxitin. This finding highlights the importance of researching the phenotypic profile of resistance to different antimicrobials and resistance genes in the different phases of pig rearing to identify the real risk of these isolates from a One Health perspective. The present study revealed the presence of samples resistant to different antibiotics in recently weaned production animal that had not been markedly exposed to antimicrobials as growth promoters or even as prophylactics. This information highlights the need for more research on the possible sharing of bacteria between sows and piglets, the environmental pressure within production environments, and the exposure of handlers during their transport, especially considering the community, hospital, and political importance of the presence of circulating resistant strains. | 2023 | 36634542 |
| 2678 | 15 | 0.9997 | Phenotypic and molecular characterization of multidrug-resistant mastitis causing pathogens in dairy cattle. This study focused on isolating antibiotic-resistant mastitogens from cow milk; 57% of 100 samples tested positive by California mastitis test. Bacterial species from each milk sample were isolated and identified using Vitek® 2 automated system. Out of the 167 bacterial strains isolated, 14 were multidrug-resistant (MDR) and were further identified as belonging to Staphylococcus spp. Enterobacter spp. Morganella spp. and Elizabethkingia spp. Staphylococcus strains showed the highest resistance by phenotypic and genotypic screening, with 8% of mastitis isolates identified as MDR. These MDR bacterial strains were also found to harbour antibiotic resistance genes such as mecA (21%), blaZ (43%), gyrA (50%), and gyrB (59%). The tissue culture plate assay showed 11 multidrug-resistant bacteria as strong biofilm formers and the biofilm-related atlE gene was analysed from Staphylococcal strain M33.1. The findings highlight a public health risk from resistant dairy bacteria, emphasizing prophylactic measures and responsible antimicrobial use to prevent zoonotic transmission. | 2025 | 41115007 |
| 5600 | 16 | 0.9997 | The Characterization and Beta-Lactam Resistance of Staphylococcal Community Recovered from Raw Bovine Milk. Staphylococci is an opportunistic bacterial population that is permanent in the normal flora of milk and poses a serious threat to animal and human health with some virulence factors and antibiotic-resistance genes. This study was aimed at identifying staphylococcal species isolated from raw milk and to determine hemolysis, biofilm, coagulase activities, and beta-lactam resistance. The raw milk samples were collected from the Düzce (Türkiye) region, and the study data represent a first for this region. The characterization of the bacteria was performed with MALDI-TOF MS and 16S rRNA sequence analysis. The presence of coa, icaB, blaZ, and mecA was investigated with PCR. A nitrocefin chromogenic assay was used for beta-lactamase screening. In this context, 84 staphylococci were isolated from 10 different species, and the dominant species was determined as S. aureus (32.14%). Although 32.14% of all staphylococci were positive for beta hemolysis, the icaB gene was found in 57.14%, coa in 46.42%, mecA in 15.47%, and blaZ in 8.33%. As a result, Staphylococcus spp. strains that were isolated from raw milk in this study contained some virulence factors at a high level, but also contained a relatively low level of beta-lactam resistance genes. However, considering the animal-environment-human interaction, it is considered that the current situation must be monitored constantly in terms of resistance concerns. It must not be forgotten that the development of resistance is in constant change among bacteria. | 2023 | 36978423 |
| 5581 | 17 | 0.9997 | Prevalence of pathogens harbouring mobile antimicrobial resistance genes and virulence factors in retail beef and mutton. Food safety is always a global issue, due to the increased dissemination of antimicrobial resistance and food poisoning related to foodborne bacterial pathogens. The purpose of this study was to assess the risk of potential foodborne bacteria of beef and mutton in retail stores. A total of 134 samples were collected from 24 local markets in Beijing, including raw and cooked beef or mutton, as well as samples derived from the corresponding environment and human beings. We obtained 674 isolates, of which Klebsiella spp. and Staphylococcus spp. were the dominant bacterial species in the meat samples and the environmental samples, respectively. Additionally, environmental bacteria are common in samples from different sources. Based on the results of antimicrobial sensitivity testing, resistance to tetracycline (with a resistance rate of 47.40%), amoxicillin + clavulanate (47.13%) and erythromycin (28.03%) were the major resistant phenotypes. According to the whole genome analysis, the extended spectrum beta-lactamase genes harboured by two K. pneumoniae strains isolated from cooked and raw beef were located on mobile elements. The major toxin genes of Bacillus cereus and adhesion- or invasion-related virulence factors were also shared among isolates from different sources. These factors pose potential risks to public health and need attention. | 2020 | 32510554 |
| 2681 | 18 | 0.9997 | Determination of the Prevalence and Antimicrobial Resistance of Enterococcus faecalis and Enterococcus faecium Associated with Poultry in Four Districts in Zambia. The presence of antimicrobial-resistant Enterococci in poultry is a growing public health concern worldwide due to its potential for transmission to humans. The aim of this study was to determine the prevalence and patterns of antimicrobial resistance and to detect drug-resistant genes in Enterococcus faecalis and E. faecium in poultry from four districts in Zambia. Identification of Enterococci was conducted using phenotypic methods. Antimicrobial resistance was determined using the disc diffusion method and antimicrobial resistance genes were detected using polymerase chain reaction and gene-specific primers. The overall prevalence of Enterococci was 31.1% (153/492, 95% CI: 27.1-35.4). Enterococcus faecalis had a significantly higher prevalence at 37.9% (58/153, 95% CI: 30.3-46.1) compared with E. faecium, which had a prevalence of 10.5% (16/153, 95% CI: 6.3-16.7). Most of the E. faecalis and E. faecium isolates were resistant to tetracycline (66/74, 89.2%) and ampicillin and erythromycin (51/74, 68.9%). The majority of isolates were susceptible to vancomycin (72/74, 97.3%). The results show that poultry are a potential source of multidrug-resistant E. faecalis and E. faecium strains, which can be transmitted to humans. Resistance genes in the Enterococcus species can also be transmitted to pathogenic bacteria if they colonize the same poultry, thus threatening the safety of poultry production, leading to significant public health concerns. | 2023 | 37107019 |
| 5533 | 19 | 0.9997 | Antibiotic resistance in potential probiotic lactic acid bacteria of fermented foods and human origin from Nigeria. INTRODUCTION: Probiotic lactobacilli are generally recognized as safe (GRAS) and are being used in several food and pharma formulations. However, growing concern of antibiotic resistance in bacterial strains of food origin and its possible transmission via functional foods is increasingly being emphasized. OBJECTIVES: This study screened potential probiotic lactic acid bacteria (LAB) strains for their phenotypic and genotypic antibiotic resistance profiles. METHODS: Susceptibility to different antibiotics was assayed by the Kirby Bauer standard disc diffusion protocol. Both conventional and SYBR-RTq-PCR were used for detection of resistance coding genes. RESULTS: A variable susceptibility pattern was documented against different antibiotic classes. LAB strains irrespective of origin displayed marked phenotypic resistance against cephalosporins, aminoglycosides, quinolones, glycopeptides; and methicillin among beta-lactams with few exceptions. In contrast, high sensitivity was recorded against macrolides, sulphonamides and carbapenems sub-group of beta-lactams with some variations. parC, associated with ciprofloxacin resistance was detected in 76.5% of the strains. Other prevalent resistant determinants observed were aac(6?)Ii (42.1%), ermB, ermC (29.4%), and tetM (20.5%). Six (?17.6%) of the isolates were free from genetic resistance determinants screened in this study. CONCLUSION: Study revealed presence of antibiotic resistance determinants among lactobacilli from both fermented foods and human sources. | 2023 | 37208603 |