# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1255 | 0 | 0.9725 | Emergence of quinupristin/dalfopristin resistance among livestock-associated Staphylococcus aureus ST9 clinical isolates. Quinupristin/dalfopristin (Q/D) is a valuable alternative to vancomycin for the treatment of meticillin-resistant Staphylococcus aureus (MRSA) infections. However, not long after Q/D was approved, bacteria with resistance to this newer antimicrobial agent were reported. To investigate the prevalence of Q/D resistance, a total of 1476 non-duplicate S. aureus isolates, including 775 MRSA, from a Chinese tertiary hospital were selected randomly from 2003 to 2013. Of the 775 MRSA, 3 (0.4%) were resistant to Q/D. All meticillin-susceptible S. aureus were susceptible to Q/D. The prevalence of Q/D resistance among S. aureus was 0.2% (3/1476). The three isolates with Q/D resistance had the same antimicrobial resistance profile, except for cefaclor and chloramphenicol. All three Q/D-resistant MRSA were positive for five streptogramin B resistance genes (ermA, ermB, ermC, msrA and msrB) and two streptogramin A resistance genes (vatC and vgaA) as determined by PCR and DNA sequencing. MRSA WZ1031 belonged to ST9-MRSA-SCCmecV-t899, whilst MRSA WZ414 and WZ480 belonged to ST9-MRSA-SCCmecNT(non-typeable)-t899. ST9 has been reported predominantly in livestock-associated (LA) MRSA in some Asian countries. The three patients with these MRSA isolates were not livestock handlers and did not keep close contact with livestock. The origin of these important LA-MRSA isolates causing human infections is not known. Taken together, Q/D resistance, which was caused by a combination of ermA-ermB-ermC-msrA-msrB-vatC-vgaA, was first found among S. aureus clinical isolates in China. The present study is the first report of the emergence of human infections caused by ST9 LA-MRSA isolates with Q/D resistance. | 2014 | 25218154 |
| 1282 | 1 | 0.9723 | Subclinical Mastitis in Selected Bovine Dairy Herds in North Upper Egypt: Assessment of Prevalence, Causative Bacterial Pathogens, Antimicrobial Resistance and Virulence-Associated Genes. Mastitis is a significant disease affecting dairy cattle farms in Egypt. The current study aimed to investigate the prevalence and major bacterial pathogens causing subclinical mastitis (SCM) in three bovine dairy herds, with a history of SCM, at three Governorates in North Upper Egypt. The antimicrobial resistance profiles and specific virulence-associated genes causing bovine SCM were investigated. One thousand sixty-quarter milk samples (QMS) were collected aseptically from 270 apparently healthy cows in three farms and examined. The total prevalence of SCM was 46% and 44.8% based on California Mastitis Test (CMT) and Somatic Cell Count (SCC), respectively. Bacteriological examination of CMT positive quarters revealed that the prevalence of bacterial isolation in subclinically mastitic quarters was 90.4% (26 and 64.3% had single and mixed isolates, respectively). The most frequent bacterial isolates were E. coli (49.8%), Staphylococcus aureus (44.9%), streptococci (44.1%) and non-aureus staphylococci (NAS) (37.1%). Antimicrobial susceptibility testing of isolates revealed a high degree of resistance to the most commonly used antimicrobial compound in human and veterinary medicine. Implementation of PCR revealed the presence of mecA and blaZ genes in 60% and 46.7% of S. aureus isolates and in 26.7% and 53.3% of NAS, respectively. Meanwhile 73.3% of streptococci isolates harbored aph(3')-IIIa gene conferring resistance to aminoglycosides and cfb gene. All E. coli isolates harbored tetA gene conferring resistance to tetracycline and sul1 gene conferring resistance to sulfonamides. The fimH and tsh genes were found in 80% and 60%, respectively. A significant association between the phenotypes and genotypes of AMR in different bacteria was recorded. The presence of a high prevalence of SCM in dairy animals impacts milk production and milk quality. The coexistence of pathogenic bacteria in milk is alarming, threatens human health and has a public health significance. Herd health improvement interventions are required to protect human health and society. | 2021 | 34072543 |
| 1258 | 2 | 0.9719 | Occurrence of antimicrobial resistance and antimicrobial resistance genes in methicillin-resistant Staphylococcus aureus isolated from healthy rabbits. BACKGROUND AND AIM: Methicillin-resistant globally, Staphylococcus aureus (MRSA) is a major cause of disease in both humans and animals. Several studies have documented the presence of MRSA in healthy and infected animals. However, there is less information on MRSA occurrence in exotic pets, especially healthy rabbits. This study aimed to look into the antimicrobial resistance profile, hidden antimicrobial-resistant genes in isolated bacteria, and to estimate prevalence of MRSA in healthy rabbits. MATERIALS AND METHODS: Two-hundreds and eighteen samples, including 42 eyes, 44 ears, 44 oral, 44 ventral thoracic, and 44 perineal swabs, were taken from 44 healthy rabbits that visited the Prasu-Arthorn Animal Hospital, in Nakornpathom, Thailand, from January 2015 to March 2016. The traditional methods of Gram stain, mannitol fermentation, hemolysis on blood agar, catalase test, and coagulase production were used to confirm the presence of Staphylococcus aureus in all specimens. All bacterial isolates were determined by antimicrobial susceptibility test by the disk diffusion method. The polymerase chain reaction was used to identify the antimicrobial-resistant genes (blaZ, mecA, aacA-aphD, msrA, tetK, gyrA, grlA, and dfrG) in isolates of MRSA with a cefoxitin-resistant phenotype. RESULTS: From 218 specimens, 185 S. aureus were isolated, with the majority of these being found in the oral cavity (29.73%) and ventral thoracic area (22.7%), respectively. Forty-seven (25.41%) MRSAs were found in S. aureus isolates, with the majority of these being found in the perineum (16, 34.04%) and ventral thoracic area (13, 27.66%) specimens. Among MRSAs, 29 (61.7%) isolates were multidrug-resistant (MDR) strains. Most of MRSA isolates were resistant to penicillin (100%), followed by ceftriaxone (44.68%) and azithromycin (44.68%). In addition, these bacteria contained the most drug-resistance genes, blaZ (47.83%), followed by gyrA (36.17%) and tetK (23.4%). CONCLUSION: This study revealed that MRSA could be found even in healthy rabbits. Some MRSAs strains were MDR-MRSA, which means that when an infection occurs, the available antibiotics were not effective in treating it. To prevent the spread of MDR-MRSA from pets to owners, it may be helpful to educate owners about effective prevention and hygiene measures. | 2022 | 36590129 |
| 1257 | 3 | 0.9718 | Antimicrobial Susceptibility Pattern in the Bacteria Isolated from Surgical Site Infection: Emphasis on Staphylococcus Aureus; Yasuj City, Southwest Iran. BACKGROUND: Surgical site infections (SSIs) in surgical wards remains the most common cause of postoperative complications and realistically is the third most common origin of healthcare-related conditions. Staphylococcus aureus is undoubtedly the most common bacteria causing SSIs. The current study aimed at investigating the antimicrobial susceptibility pattern in bacteria isolated from SSIs, evaluation of tetracycline resistance genes, and SCCmec typing in S. aureus isolates isolated from patients with SSIs from 2018 to 2019 in Yasuj, Kohgiluyeh, and Boyer-Ahmad Province, Iran. METHODS: This study diligently investigated 240 potential patients. Antimicrobial susceptibility testing was performed properly by the disk diffusion method. For the final confirmation of isolated bacteria, PCR was used. The presence of tet genes and SCCmec typing was carried out by multiplex PCR. RESULTS: The results showed that the most common isolated pathogens included S. aureus, E. coli, P. aeruginosa, Coagulase-negative Staphylococci, and K. pneumonia in 58.8%, 19.8%, 9.2%, 6.8% and 5.4% of cases, respectively. The majority of the Gram positive isolates were resistant against penicillin (86%) and Gram negative were resistant against ciprofloxacin (75.6%). In isolates of Staphylococcus aureus, the mecA gene was detected in 63.6% of isolates. The predominant SCCmec types were type III (59.1%) and type I (18.4%). The tetK and tetM genes were detected in 80.7% and 71.9% of the S. aureus isolates, respectively. There was a statistically significant difference between tet genes (tetK and tetM) from the viewpoint of resistance to tetracycline (p = 0.024). CONCLUSIONS: According to the results of the current study, it is recommended to administer vancomycin, amikacin, and imipenem in Yasuj to treat SSIs. | 2021 | 33616327 |
| 5432 | 4 | 0.9718 | First large-scale study of antimicrobial susceptibility data, and genetic resistance determinants, in Fusobacterium necrophorum highlighting the importance of continuing focused susceptibility trend surveillance. OBJECTIVES: The objective of the study was to explore antimicrobial resistance gene determinant, and phenotypic antibiotic susceptibility, data for Fusobacterium necrophorum from a collection of UK strains. Antimicrobial resistance genes detected in publicly available assembled whole genome sequences were investigated for comparison. METHODS: Three hundred and eighty five F. necrophorum strains (1982-2019) were revived from cryovials (Prolab). Subsequent to sequencing (Illumina) and quality checking, 374 whole genomes were available for analysis. Genomes were interrogated, using BioNumerics (bioMérieux; v 8.1), for the presence of known antimicrobial resistance genes (ARGs). Agar dilution susceptibility results for 313 F. necrophorum isolates (2016-2021) were also examined. RESULTS: The phenotypic data for the 313 contemporary strains demonstrated potential resistance to penicillin in three isolates, using EUCAST v 11.0 breakpoints, and 73 (23%) strains using v 13.0 analysis. All strains were susceptible to multiple agents using v 11.0 guidance other than clindamycin (n = 2). Employing v 13.0 breakpoints, metronidazole (n = 3) and meropenem (n = 13) resistance were also detected. The tet(O), tet(M), tet(40), aph(3')-III, ant(6)-la and bla(OXA-85) ARGs were present in publicly available genomes. tet(M), tet(32), erm(A) and erm(B) were found within the UK strains, with correspondingly raised clindamycin and tetracycline minimum inhibitory concentrations. CONCLUSIONS: Susceptibility to antibiotics recommended for the treatment of F. necrophorum infections should not be assumed. With evidence of potential ARG transmission from oral bacteria, and the detection of a transposon-mediated beta-lactamase resistance determinant in F. necrophorum, surveillance of both phenotypic and genotypic antimicrobial susceptibility trends must continue, and increase. | 2023 | 36871786 |
| 1253 | 5 | 0.9714 | Phenotypic and Genotypic Assessment of Antibiotic Resistance and Genotyping of vacA, cagA, iceA, oipA, cagE, and babA2 Alleles of Helicobacter pylori Bacteria Isolated from Raw Meat. BACKGROUND: Foodstuffs with animal origins, particularly meat, are likely reservoirs of Helicobacter pylori. PURPOSE: An existing survey was accompanied to assess phenotypic and genotypic profiles of antibiotic resistance and genotyping of vacA, cagA, cagE, iceA, oipA, and babA2 alleles amongst the H. pylori bacteria recovered from raw meat. METHODS: Six-hundred raw meat samples were collected and cultured. H. pylori isolates were tested using disk diffusion and PCR identification of antibiotic resistance genes and genotyping. RESULTS: Fifty-two out of 600 (8.66%) raw meat samples were contaminated with H. pylori. Raw ovine meat (13.07%) had the uppermost contamination. H. pylori bacteria displayed the uppermost incidence of resistance toward tetracycline (82.69%), erythromycin (80.76%), trimethoprim (65.38%), levofloxacin (63.46%), and amoxicillin (63.46%). All H. pylori bacteria had at least resistance toward one antibiotic, even though incidence of resistance toward more than eight antibiotics was 28.84%. Total distribution of rdxA, pbp1A, gyrA, and cla antibiotic resistance genes were 59.61%, 51.92%, 69.23%, and 65.38%, respectively. VacA s1a (84.61%), s2 (76.92%), m1a (50%), m2 (39.13%), iceA1 (38.46%), and cagA (55.76%) were the most generally perceived alleles. S1am1a (63.46%), s2m1a (53.84%), s1am2 (51.92%), and s2m2 (42.30%) were the most generally perceived genotyping patterns. Frequency of cagA-, oipA-, and babA2- genotypes were 44.23%, 73.07%, and 80.76%, respectively. A total of 196 combined genotyping patterns were also perceived. CONCLUSION: The role of raw meat, particularly ovine meat, in transmission of virulent and resistant H. pylori bacteria was determined. VacA and cagA genotypes had the higher incidence. CagE-, babA2-, and oipA- H. pylori bacteria had the higher distribution. Supplementary surveys are compulsory to originate momentous relations between distribution of genotypes, antibiotic resistance, and antibiotic resistance genes. | 2020 | 32099418 |
| 1256 | 6 | 0.9714 | Prevalence of antimicrobial resistant genes in Bacteroides spp. isolated in Oita Prefecture, Japan. INTRODUCTION: Bacteroides spp. are the most common anaerobic bacteria isolated from the human gastrointestinal tract. Several resistant genes are present in Bacteroides spp. However, most studies have focused on the prevalence of the cfiA gene in Bacteroides fragilis alone. We assessed the susceptibility to antimicrobial agents and the prevalence of cepA, cfiA, cfxA, ermF, nim, and tetQ genes in Bacteroides strains isolated from clinical specimens in our hospital. METHODS: We isolated 86 B. fragilis and 58 non-fragilis Bacteroides strains from human clinical specimens collected from January 2011 to November 2021. Resistance against piperacillin (PIPC), cefotaxime (CTX), cefepime (CFPM), meropenem (MEPM), clindamycin, and minocycline was determined. RESULTS: The resistant rates of penicillins and cephalosporins in non-fragilis isolates were significantly higher than those in B. fragilis isolates. In B. fragilis isolates, the resistant rates of PIPC, CTX, and CFPM in cfxA-positive isolates were significantly higher than those in cfxA-negative isolates (71% vs. 16%, 77% vs. 19%, and 77% vs. 30%, respectively). Thirteen B. fragilis isolates harbored the cfiA gene, two of which were resistant to MEPM. Six of the 13 cfiA-positive B. fragilis isolates were heterogeneously resistant to MEPM. CONCLUSION: It is important to evaluate the use of MEPM as empirical therapy for Bacteroides spp. infections, considering the emergence of carbapenem resistance during treatment, existence of MEPM-resistant strains, and heterogeneous resistance. | 2023 | 36473684 |
| 5240 | 7 | 0.9714 | Dynamics of Antimicrobial Resistance Carriage in Koalas (Phascolarctos Cinereus) and Pteropid Bats (Pteropus Poliocephalus) Before, During and After Wildfires. In the 2019-2020 summer, wildfires decimated the Australian bush environment and impacted wildlife species, including koalas (Phascolarctos cinereus) and grey headed flying fox pups (Pteropid bats, Pteropus poliocephalus). Consequently, hundreds of koalas and thousands of bat pups entered wildlife hospitals with fire-related injuries/illness, where some individuals received antimicrobial therapy. This study investigated the dynamics of antimicrobial resistance (AMR) in pre-fire, fire-affected and post-fire koalas and Pteropid bat pups. PCR and DNA sequencing were used to screen DNA samples extracted from faeces (koalas and bats) and cloacal swabs (koalas) for class 1 integrons, a genetic determinant of AMR, and to identify integron-associated antibiotic resistance genes. Class 1 integrons were detected in 25.5% of koalas (68 of 267) and 59.4% of bats (92 of 155). Integrons contained genes conferring resistance to aminoglycosides, trimethoprim and beta-lactams. Samples were also screened for blaTEM (beta-lactam) resistance genes, which were detected in 2.6% of koalas (7 of 267) and 25.2% of bats (39 of 155). Integron occurrence was significantly higher in fire-affected koalas in-care compared to wild pre-fire koalas (P < 0.0001). Integron and blaTEM occurrence were not significantly different in fire-affected bats compared to pre-fire bats (P > 0.05), however, their occurrence was significantly higher in fire-affected bats in-care compared to wild fire-affected bats (P < 0.0001 and P = 0.0488 respectively). The observed shifts of AMR dynamics in wildfire-impacted species flags the need for judicious antibiotic use when treating fire-affected wildlife to minimise unwanted selective pressure and negative treatment outcomes associated with carriage of resistance genes and antibiotic resistant bacteria. | 2024 | 38332161 |
| 2364 | 8 | 0.9710 | Association of multilocus sequencing types and antimicrobial resistance profiles of methicillin-resistant Mammaliicoccus sciuri in animals in Southern Thailand. BACKGROUND AND AIM: Mammaliicoccus sciuri, formerly known as Staphylococcus sciuri, is an opportunistic pathogen in the environment, human and animal mucosa, and skin. Although this pathogen is becoming more resistant to drugs and harmful to animals and humans, basic knowledge of this pathogen remains limited. This study aimed to investigate a new multilocus sequencing type (MLST) related to the antibiotic resistance pattern of M. sciuri from animals in southern Thailand. MATERIALS AND METHODS: We used 11 methicillin-resistant M. sciuri (MRMS) isolates in this study which were obtained from six horses, four cows, and one chicken of the previous study. Antimicrobial resistance (AMR) was re-evaluated based on the minimum inhibitory concentration using the VITEK(®) 2 automated system. Three AMR genes were examined, namely mecA, mecC, and blaZ. Staphylococcal chromosomal cassette mec (SCCmec) gene detection was performed through the multiplex polymerase chain reaction (PCR). Internal segments of the seven housekeeping genes, ack, aroE, ftsZ, glpK, gmk, pta1, and tpiA, were used for multilocus sequence typing. The population of resistant bacteria and the types of multidrug-resistant, extensively drug-resistant, and pandemic drug-resistant bacteria were classified through descriptive analysis. RESULTS: mecA and blaZ genes were detected in all isolates; however, the mecC gene was not observed in any isolate based on the PCR results. All MRMS isolates revealed a non-typable SCCmec. Seven MLSTs (71, 81, 120, 121, 122, 199, and 200) were identified in this study. CONCLUSION: The characteristics of MRMS in Southern Thailand were variable, particularly in cattle and horses. The antibiogram and SCCmec types of this pathogen remain concerns with regard to antibiotic-resistant gene transmission among Staphylococcus and Mammaliicoccus species. All MLSTs in Thailand revealed the distribution among clones in Asia, including the virulence of a zoonotic clone in Southern Thailand. | 2023 | 37041994 |
| 2393 | 9 | 0.9709 | Detection of a mecC-positive Staphylococcus saprophyticus from bovine mastitis in Argentina. INTRODUCTION: Bovine mastitis causes important economic losses in the dairy industry. Coagulase-negative staphylococci (CNS) are a group of bacteria commonly isolated from bovine mastitis and can display resistance to a wide range of antimicrobial agents. OBJECTIVES: The objective of this study was to determine staphylococcal resistance towards β-lactam, macrolide and lincosamide antimicrobials in quarters previously treated with third-generation cephalosporin and after lincosamide intramammary therapy. METHODS: Sick quarters of eighteen cows from Villaguay, Entre Ríos (Argentina) with clinical mastitis were studied. All staphylococcal isolates were tested by disk diffusion for their antimicrobial susceptibilities. Cefoxitin resistance was investigated by PCR and sequencing for both the mecA and mecC genes. RESULTS: Resistances to penicillin, oxacillin and cefoxitin were observed, whereas no resistance to macrolide and lincosamide was detected. A cefoxitin-resistant Staphylococcus saprophyticus was found to be mecA-negative but mecC-positive. CONCLUSIONS: This study reports for the first time the mecC gene from a CNS in bovine mastitis in South America. Because CNS may act as reservoirs of antimicrobial resistance genes, they can be seen as a potential public health threat with respect to antimicrobial resistance and the development of multiple resistance. Also, the emergence of methicillin-resistant phenotypes will limit therapeutic options. | 2017 | 28732791 |
| 1267 | 10 | 0.9709 | Detection and characterization of methicillin-resistant and susceptible coagulase-negative staphylococci in milk from cows with clinical mastitis in Tunisia. OBJECTIVES: This study investigated prevalence of methicillin-resistant (MR) and methicillin-susceptible (MS) coagulase-negative staphylococci (CNS) and the implicated mechanisms of resistance and virulence in milk of mastitis cows. In addition, the presence of SCCmec type was analyzed in MR Staphylococcus epidermidis (MRSE). RESULTS: Three hundred milk samples from cows with clinical mastitis were obtained from 30 dairy farms in different regions of Tunisia. Sixty-eight of the 300 tested samples contained CNS strains. Various CNS species were identified, with Staphylococcus xylosus being the most frequently found (40%) followed by Staphylococcus warneri (12%). The mecA gene was present in 14 of 20 MR-CNS isolates. All of them were lacking the mecC gene. The SCCmecIVa was identified in four MRSE isolates. Most of CNS isolates showed penicillin resistance (70.6%) and 58.3% of them carried the blaZ gene. MR-CNS isolates (n = 20) showed resistance to erythromycin, tetracycline and trimethoprim-sulfametoxazole harboring different resistance genes such us erm(B), erm(T), erm(C), mph(C) or msr(A), tet(K) and dfr(A). However, a lower percentage of resistance was observed among 48 MS-CNS isolates: erythromycin (8.3%), tetracycline (6.2%), streptomycin (6.2%), clindamycin (6.2%), and trimethoprim-sulfametoxazole (2%). The Inu(B) gene was detected in one Staphylococcus xylosus strain that showed clindamycin resistance. The virulence gene tsst-1 was observed in one MR-CNS strain. DISCUSSION: Coagulase-negative staphylococci containing a diversity of antimicrobial resistance genes are frequently detected in milk of mastitis cows. This fact emphasizes the importance of identifying CNS when an intramammary infection is present because of the potential risk of lateral transfer of resistant genes among staphylococcal species and other pathogenic bacteria. | 2018 | 30077662 |
| 5385 | 11 | 0.9709 | Environmental heterogeneity of Staphylococcus species from alkaline fermented foods and associated toxins and antimicrobial resistance genetic elements. Different samples of three products including Bikalga and Soumbala from Burkina Faso (West Africa) and Ntoba Mbodi from Congo-Brazzaville (Central Africa) were evaluated. The bacteria (400) were phenotyped and genotypically characterized by Rep-PCR, PFGE, 16S rRNA and rpoB gene sequencing and spa typing. Their PFGE profiles were compared with those of 12,000 isolates in the Center for Disease Control (CDC, USA) database. They were screened for the production of enterotoxins, susceptibility to 19 antimicrobials, presence of 12 staphylococcal toxin and 38 AMR genes and the ability to transfer erythromycin and tetracycline resistance genes to Enterococcus faecalis JH2-2. Fifteen coagulase negative (CoNS) and positive (CoPS) species characterized by 25 Rep-PCR/PFGE clusters were identified: Staphylococcus arlettae, S. aureus, S. cohnii, S. epidermidis, S. gallinarum, S. haemolyticus, S. hominis, S. pasteuri, S. condimenti, S. piscifermentans, S. saprophyticus, S. sciuri, S. simulans, S. warneri and Macrococcus caseolyticus. Five species were specific to Soumbala, four to Bikalga and four to Ntoba Mbodi. Two clusters of S. gallinarum and three of S. sciuri were particular to Burkina Faso. The S. aureus isolates exhibited a spa type t355 and their PFGE profiles did not match any in the CDC database. Bacteria from the same cluster displayed similar AMR and toxin phenotypes and genotypes, whereas clusters peculiar to a product or a location generated distinct profiles. The toxin genes screened were not detected and the bacteria did not produce the staphylococcal enterotoxins A, B, C and D. AMR genes including blazA, cat501, dfr(A), dfr(G), mecA, mecA1, msr(A) and tet(K) were identified in CoNS and CoPS. Conjugation experiments produced JH2-2 isolates that acquired resistance to erythromycin and tetracycline, but no gene transfer was revealed by PCR. The investigation of the heterogeneity of Staphylococcus species from alkaline fermented foods, their relationship with clinical and environmental isolates and their safety in relation to antimicrobial resistance (AMR) and toxin production is anticipated to contribute to determining the importance of staphylococci in alkaline fermented foods, especially in relation to the safety of the consumers. | 2019 | 31670141 |
| 1300 | 12 | 0.9709 | Genotypic and Phenotypic-Based Assessment of Antibiotic Resistance and Profile of Staphylococcal Cassette Chromosome mec in the Methicillin-Resistant Staphylococcus aureus Recovered from Raw Milk. BACKGROUND: Multidrug resistant methicillin-resistant Staphylococcus aureus (MRSA) bacteria are determined to be one of the chief causes of foodborne diseases around the world. PURPOSE: This research was done to assess the genotypic and phenotypic profiles of antibiotic resistance and distribution of Staphylococcus cassette chromosome mec (SCCmec) types amongst the MRSA bacteria recovered from raw milk. METHODS: Five-hundred and ninety raw milk samples were collected and examined. MRSA bacteria were recognized using susceptibility evaluation toward oxacillin and cefoxitin disks. Profile of antibiotic resistance genes and SCCmec types were determined using the PCR. Antibiotic resistance pattern of isolates was examined using the disk diffusion. RESULTS: Thirty-nine out of 590 raw milk samples (6.61%) were positive for S. aureus. Twenty-eight out of 39 (71.79%) bacteria were defined as MRSA bacteria. Raw buffalo (80%) milk samples had the maximum incidence of MRSA, while raw camel (33.33%) had the minimum. MRSA bacteria harbored the maximum incidence of resistance toward penicillin (100%), tetracycline (100%), erythromycin (82.14%), gentamicin (78.57%) and trimethoprim-sulfamethoxazole (78.57%). Incidence of resistance toward more than eight classes of antibiotic agents was 28.57%. The most frequently distinguished antibiotic resistance markers were blaZ (100%), tetK (85.71%), dfrA1 (71.42%), aacA-D (67.85%), ermA (50%) and gyrA (42.85%). SCCmec IVa (29.62%), V (25%), III (14.81%) and IVb (11.11%) were the most frequently distinguished types. CONCLUSION: Raw milk of dairy animals maybe sources of multidrug resistant MRSA which pose a hygienic threat concerning the consumption of raw milk in Iran. Nevertheless, further investigations are necessary to understand supplementary epidemiological features of MRSA in raw milk. | 2020 | 32099419 |
| 2376 | 13 | 0.9709 | Molecular characterization and antimicrobial susceptibility of methicillin-resistant staphylococcus aureus isolates from clinical samples and asymptomatic nasal carriers in Istanbul (Turkey). BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has been a widespread problem in Turkish hospitals. AIMS: The aim of this study was to investigate the staphylococcal toxin genes of the clinical and nasal MRSA isolates, and their antibiotic resistance profiles. MATERIALS AND METHODS: Isolation of nasal and clinical bacteria was done following standard microbiological methods. The presence of antimicrobial resistance genes (mec A, pvl, tsst-1, and SEs genes) was determined using the real-time polymerase chain reaction (PCR) assay. RESULTS: Among nasal MRSA isolates, 66.7% were toxigenic. The distribution of genes was as follows: pvl 26.7%, tsst-1 3.3%, and SEs 36.7%. Therefore, the nasal MRSA isolates had a rate of 23.3% multidrug resistance (MDR) pattern to the non-beta-lactams antibiotics. All (100%) clinical MRSA isolates were found to be toxigenic. The distribution of genes was as follows; pvl 10%, tsst-1 6.7%, and SEs 100%. The clinical MRSA isolates had a rate of 60% MDR. CONCLUSIONS: Following detection of pvl, tsst-1, and SEs among nasal and clinical MRSA isolates, and the presence of high antimicrobial resistance, the spread of these strains may be an additional factor contributing to the emergence of community-acquired (CA)-MRSA and hospital-acquired (HA)-MRSA. This study is the first to determine the resistance to linezolid and tigecycline in both nasal and clinical MRSA isolates, for the first time in Turkey. All nasal and clinical MRSA isolates were uniformly susceptible to vancomycin and quinupristin-dalfopristin. Our findings show that MRSA infections in Turkey can be empirically treated with vancomycin and quinupristin-dalfopristin based on the lack of demonstrable resistance to these drugs. | 2021 | 34290175 |
| 2383 | 14 | 0.9709 | Risk Factors for Antimicrobial Resistance of Staphylococcus Species Isolated from Dogs with Superficial Pyoderma and Their Owners. The microbial communities on the skin of dogs include several species of bacteria, which contribute to skin health and disease. Staphylococcus pseudintermedius, cultured at high frequency from the skin of dogs, is an opportunistic pathogen causing superficial pyoderma. Effective treatment against S. pseudintermedius infections is an important issue in veterinary medicine. However, multiple antibiotic-resistant mechanisms gradually developed by bacteria make treatment more challenging nowadays. Drug-resistant genes may have the chance to be transferred from infected dogs to other staphylococci in humans. The objective of this survey is to investigate the bacterial species that cause canine superficial pyoderma and characterize the antibiotic-resistant profiles and drug-resistant genes of isolated S. pseudintermedius. In addition, the possible risk factors causing S. pseudintermedius colonizing owners were also evaluated by a questionnaire survey. Sixty-five bacteria were isolated from dogs with superficial pyoderma, which included 47 S. pseudintermedius (72.3%), 12 other staphylococci (18.5%), 4 other Gram-positive bacteria (6.2%) and 2 Gram-negative bacteria (3.1%). Strains containing mecA and blaZ genes showed multiple-drug resistance characteristics. Dogs that received antimicrobial treatment within a recent month were at significantly higher risk of MRSP infections. Only five S. pseudintermedius strains (8.33%) were isolated from 60 samples of owners. Risk factor analysis indicated there was no significant association between S. pseudintermedius isolated from dogs and owners, but the "Keeping three or more dogs" and "Dogs can lick the owner's face" have high odds ratios of 3.503 and 5.712, respectively. MRSP isolates belonged to three different dru types, including dt11y (29.41%), dt11a (47.06%) and dt10cp (23.53%). In conclusion, the major pathogen of canine superficial pyoderma is found to be S. pseudintermedius in Taiwan, and isolates which are mecA- or blaZ-positive are generally more resistant to commonly used antibiotics. Although S. pseudintermedius isolated from the owners might be transferred from their dogs, definite risk factors should be examined in the future study. | 2022 | 35878323 |
| 5244 | 15 | 0.9709 | Potentially pathogenic bacteria and antimicrobial resistance in bioaerosols from cage-housed and floor-housed poultry operations. BACKGROUND: Antibiotics are used in animal confinement buildings, such as cage-housed (CH) and floor-housed (FH) poultry operations, to lower the likeliness of disease transmission. In FH facilities, antibiotics may also be used at sub-therapeutic levels for growth promotion. Low levels of antibiotic create a selective pressure toward antimicrobial resistance (AMR) in chicken fecal bacteria. OBJECTIVE: The objective of this study was to compare bacteria and AMR genes in bioaerosols from CH and FH poultry facilities. METHODS: Bioaerosols were collected from 15 CH and 15 FH poultry operations, using stationary area samplers as well as personal sampling devices. Bacteria concentrations were determined by genus- or species-specific quantitative polymerase chain reaction (PCR) and AMR genes were detected using endpoint PCR. RESULTS: Enterococcus spp., Escherichia coli, and Staphylococcus spp. were significantly higher in bioaerosols of FH poultry operations than CH bioaerosols (P < 0.001) while Clostridium perfringens was significantly higher in area bioaerosols of CH operations than FH area bioaerosols (P < 0.05). Campylobacter spp. were detected only in bioaerosols of FH facilities. Zinc bacitracin resistance gene, bcrR, erythromycin resistance gene, ermA, and tetracycline resistance gene, tetA/C, were more prevalent in bioaerosols of FH facilities than CH bioaerosols (P < 0.01, P < 0.01, and P < 0.05, respectively). CONCLUSIONS: Most bacteria are more concentrated and most AMR genes are more prevalent in bioaerosols of FH poultry operations, where growth-promoting antibiotics may be used. | 2012 | 22156572 |
| 1302 | 16 | 0.9707 | A survey of prevalence and phenotypic and genotypic assessment of antibiotic resistance in Staphylococcus aureus bacteria isolated from ready-to-eat food samples collected from Tehran Province, Iran. BACKGROUND: Resistant Staphylococcus aureus (S. aureus) bacteria are considered among the major causes of foodborne diseases. This survey aims to assess genotypic and phenotypic profiles of antibiotic resistance in S. aureus bacteria isolated from ready-to-eat food samples. METHODS: According to the previously reported prevalence of S. aureus in ready-to-eat food samples, a total of 415 ready-to-eat food samples were collected from Tehran province, Iran. S. aureus bacteria were identified using culture and biochemical tests. Besides, the phenotypic antibiotic resistance profile was determined by disk diffusion. In addition, the genotypic pattern of antibiotic resistance was determined using the PCR. RESULTS: A total of 64 out of 415 (15.42%) ready-to-eat food samples were contaminated with S. aureus. Grilled mushrooms and salad olivieh harbored the highest contamination rate of (30%), while salami samples harbored the lowest contamination rate of 3.33%. In addition, S. aureus bacteria harbored the highest prevalence of resistance to penicillin (85.93%), tetracycline (85.93%), gentamicin (73.43%), erythromycin (53.12%), trimethoprim-sulfamethoxazole (51.56%), and ciprofloxacin (50%). However, all isolates were resistant to at least four antibiotic agents. Accordingly, the prevalence of tetK (70.31%), blaZ (64.06%), aacA-D (57.81%), gyrA (50%), and ermA (39.06%) was higher than that of other detected antibiotic resistance genes. Besides, AacA-D + blaZ (48.43%), tetK + blaZ (46.87%), aacA-D + tetK (39.06%), aacA-D + gyrA (20.31%), and ermA + blaZ (20.31%) were the most frequently identified combined genotypic patterns of antibiotic resistance. CONCLUSION: Ready-to-eat food samples may be sources of resistant S. aureus, which pose a hygienic threat in case of their consumption. However, further investigations are required to identify additional epidemiological features of S. aureus in ready-to-eat foods. | 2021 | 34635183 |
| 828 | 17 | 0.9706 | Screening for Resistant Bacteria, Antimicrobial Resistance Genes, Sexually Transmitted Infections and Schistosoma spp. in Tissue Samples from Predominantly Vaginally Delivered Placentae in Ivory Coast and Ghana. Medical complications during pregnancy have been frequently reported from Western Africa with a particular importance of infectious complications. Placental tissue can either become the target of infectious agents itself, such as, e.g., in the case of urogenital schistosomiasis, or be subjected to contamination with colonizing or infection-associated microorganisms of the cervix or the vagina during vaginal delivery. In the retrospective cross-sectional assessment presented here, the quantitative dimension of infection or colonization with selected resistant or pathogenic bacteria and parasites was regionally assessed. To do so, 274 collected placental tissues from Ivory Coastal and Ghanaian women were subjected to selective growth of resistant bacteria, as well as to molecular screening for beta-lactamase genes, Schistosoma spp. and selected bacterial causative agents of sexually transmitted infections (STI). Panton-Valentine-negative methicillin-resistant Staphylococcus aureus (MRSA) was grown from 1.8% of the tissue samples, comprising the spa types t008 and t688, as well as the newly detected ones, t12101 (n = 2) and t12102. While the culture-based recovery of resistant Enterobacterales and nonfermentative rod-shaped Gram-negative bacteria failed, molecular assessments confirmed beta-lactamase genes in 31.0% of the samples with multiple detections of up to four resistance genes per sample and bla(CTX-M), bla(IMP), bla(GES), bla(VIM), bla(OXA-58)-like, bla(NDM), bla(OXA-23)-like, bla(OXA-48)-like and bla(KPC) occurring in descending order of frequency. The beta-lactamase genes bla(OXA-40/24)-like, bla(NMC_A/IMI), bla(BIC), bla(SME), bla(GIM) and bla(DIM) were not detected. DNA of the urogenital schistosomiasis-associated Schistosoma haematobium complex was recorded in 18.6% of the samples, but only a single positive signal for S. mansoni with a high cycle-threshold value in real-time PCR was found. Of note, higher rates of schistosomiasis were observed in Ghana (54.9% vs. 10.3% in Ivory Coast) and Cesarean section was much more frequent in schistosomiasis patients (61.9% vs. 14.8% in women without Schistosoma spp. DNA in the placenta). Nucleic acid sequences of nonlymphogranuloma-venereum-associated Chlamydia trachomatis and of Neisseria gonorrhoeae were recorded in 1.1% and 1.9% of the samples, respectively, while molecular attempts to diagnose Treponema pallidum and Mycoplasma genitalium did not lead to positive results. Molecular detection of Schistosoma spp. or STI-associated pathogens was only exceptionally associated with multiple resistance gene detections in the same sample, suggesting epidemiological distinctness. In conclusion, the assessment confirmed considerable prevalence of urogenital schistosomiasis and resistant bacterial colonization, as well as a regionally expected abundance of STI-associated pathogens. Continuous screening offers seem advisable to minimize the risks for the pregnant women and their newborns. | 2023 | 37623959 |
| 1276 | 18 | 0.9706 | Should we leave the paper currency? A microbiological examination. OBJECTIVE: Pathogens can be transmitted to banknotes due to the personal unhygienic habits. The aim of study was to find the possible pathogens on the banknotes circulating in the market and also to present their antibacterial resistance and their various virulence factors using genotypic and phenotypic methods. METHODS: A total of 150 samples of bank-notes were randomly collected between August 2017 and March 2018. VITEK systems were used for identification and antimicrobial susceptibility testing respectively. Antimicrobial resistance genes (mecA, van, extended-spectrum β-lactamase [ESBL] and carbapenemases) and staphyloccoccal virulence genes (staphyloccoccal enterotoxins [SEs], pvl, and tsst-1) were determined using with real-time PCR. RESULTS: Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Enterococcus spp., Gram-negative enteric bacteria, non-fermentative Gram-negative bacteria and Candida spp. were detected 48%, 54.7%, 56%, 21.3%, 18.7%, and 4%, respectively. Methicillin-resistant S. aureus, vancomycin-resistant enterococci and ESBL producing Gram-negative were found 46.8%, 1.3%, and 28.7%, respectively. Pvl, tsst-1, and SEs genes were found in a 2.8/4.9%, 1.4/1.2%, and 100/ 87.8% of the S. aureus/CoNS strains, respectively. The sea gene was found the most common enterotoxigenic gene. blaTEM, blaSHV, blaCTX-M-2, blaCTX-M-1, blaKPC, and blaOXA-48 were found 55.8%, 46.5%, 41.2%, 18.6%, 18.6%, and 18.6%, respectively in Gram-negative strains. CONCLUSIONS: These results is very important to highlight hygienic status of paper currencies. This can be considered as an indication that banknotes may contribute to the spread of pathogens and antimicrobial resistance. Therefore, we may need to start using alternative products instead of banknotes. | 2020 | 32066229 |
| 1283 | 19 | 0.9705 | Antimicrobial Resistance Profiles of Staphylococcus Isolated from Cows with Subclinical Mastitis: Do Strains from the Environment and from Humans Contribute to the Dissemination of Resistance among Bacteria on Dairy Farms in Colombia? Staphylococcus is a very prevalent etiologic agent of bovine mastitis, and antibiotic resistance contributes to the successful colonization and dissemination of these bacteria in different environments and hosts on dairy farms. This study aimed to identify the antimicrobial resistance (AMR) genotypes and phenotypes of Staphylococcus spp. isolates from different sources on dairy farms and their relationship with the use of antibiotics. An antimicrobial susceptibility test was performed on 349 Staphylococcus strains (S. aureus, n = 152; non-aureus staphylococci (NAS), n = 197) isolated from quarter milk samples (QMSs) from cows with subclinical mastitis (176), the teats of cows (116), the milking parlor environment (32), and the nasal cavities of milk workers (25). Resistance and multidrug resistance percentages found for S. aureus and NAS were (S. aureus = 63.2%, NAS = 55.8%) and (S. aureus = 4.6%, NAS = 11.7%), respectively. S. aureus and NAS isolates showed resistance mainly to penicillin (10 IU) (54.1% and 32.4%) and ampicillin (10 mg) (50.3% and 27.0%) drugs. The prevalence of AMR Staphylococcus was higher in environmental samples (81.3%) compared to other sources (52.6-76.0%). In S. aureus isolates, the identification of the blaZ (83.9%), aacAaphD (48.6%), ermC (23.5%), tetK (12.9%), and mecA (12.1%) genes did not entirely agree with the AMR phenotype. We conclude that the use of β-lactam antibiotics influences the expression of AMR in Staphylococcus circulating on dairy farms and that S. aureus isolates from the environment and humans may be reservoirs of AMR for other bacteria on dairy farms. | 2023 | 37998777 |