# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1223 | 0 | 0.9808 | 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 |
| 1227 | 1 | 0.9804 | 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 |
| 1114 | 2 | 0.9799 | Third-Generation Cephalosporin Resistance in Intrinsic Colistin-Resistant Enterobacterales Isolated from Retail Meat. Consumption of retail meat contaminated with antimicrobial-resistant (AMR) bacteria is a common route for transmitting clinically relevant resistant bacteria to humans. Here, we investigated the genotypic and phenotypic resistance profiles of intrinsic colistin-resistant (ICR) Enterobacterales isolated from retail meats. ICR Enterobacterales were isolated from 103 samples of chicken, 103 samples of pork, and 104 samples of beef purchased from retail shops in Japan, using colistin-containing media, and their antimicrobial susceptibility was examined. Serratia spp. (440 isolates) showed resistance to cefotaxime (19 isolates, 4.3%), tetracycline (15 isolates, 3.4%), and other antimicrobials (<1%). Hafnia spp. (136) showed resistance to cefotaxime (12 isolates, 8.6%), ceftazidime (four isolates, 2.9%), and tetracycline (two isolates, 1.4%). Proteus spp. (39) showed resistance to chloramphenicol (four isolates, 10.3%), sulfamethoxazole-trimethoprim (four isolates, 10.3%), cefotaxime (two isolates, 5.1%), kanamycin (two isolates, 5.1%), and gentamicin (one isolate, 2.6%). Cedecea spp. (22) were resistant to tetracycline (two isolates, 9.1%) whereas Morganella spp. (11) were resistant to tetracycline (four isolates, 36.4%) and chloramphenicol (one isolate, 9.2%). The resistance genes bla(fonA), bla(ACC), and bla(DHA) were detected in cefotaxime-resistant Serratia spp., Hafnia spp., and Morganella spp. isolates, respectively. This emergence of antimicrobial resistance in ICR Enterobacterales may pose a public health risk. | 2021 | 34943649 |
| 2129 | 3 | 0.9796 | Screening of antibiotic resistance genes in pathogenic bacteria isolated from tiny freshwater shrimp (Macrobrachium lanchesteri) and "Kung Ten", the uncooked Thai food. OBJECTIVE: This study aimed to isolate and identify of pathogenic bacteria in tiny freshwater shrimp (Macrobrachium lanchesteri) and in Kung Ten, which is an unusual Thai cuisine that eaten alive shrimp directly. Antimicrobial susceptibility test and identification of antibiotic resistance genes for isolated bacteria were conducted. MATERIALS AND METHODS: Eighty of fresh shrimp samples and forty of Kung Ten salads were collected from four fresh markets, which were located in Bangkok and Nonthaburi province (N = 120). The isolation, identification, and antimicrobial susceptibility test of pathogenic bacteria were done following the Clinical and Laboratory Standards Institute guidelines. Antibiotic-resistant bacteria were screened for β-lactamase relating genes, such as AmpC (MOX and ACC genes), bla (CTX-M), and Int1 genes. RESULTS: The number of bacterial isolates in tiny freshwater shrimp and Kung Ten salad was 136 and 65, respectively. Aeromonas caviae, A. hydrophilla, Proteus penneri, Proteus vulgaris, and Klebsiella pneumoniae were commonly found. Ampicillin, amoxicillin/clavulanic, cefuroxime, tetracycline, and trimethoprim/sulfamethoxazole resistance were observed, and common antibiotic-resistant bacteria were A. caviae, P. vulgaris, Enterobacter Aerogenes, and K. pneumoniae. A. caviae, P. penneri, K. Pneumoniae, and A. hydrophilla were positive for MOX gene; bla (CTX-M), and Int1 genes; ACC and Int1 genes; and ACC gene, respectively. CONCLUSION: Raw or uncooked shrimps in Kung Ten salad may a risk in foodborne diseases due to positive for pathogenic bacterial isolates. However, hygienic control on food preparation is difficult to apply because of the difficulty of changing in local Thai food behavior. | 2020 | 32219114 |
| 1236 | 4 | 0.9796 | Molecular characterization of antimicrobial resistance in Gram-negative bacteria isolated from bovine mastitis in Egypt. The aim of this study was to characterize the genetic basis of multidrug resistance in Gram-negative bacteria isolated from bovine mastitis cases in Egypt. Multidrug resistance phenotypes were found in 34 of 112 (30.4%) Gram-negative bacterial isolates, which harbored at least one antimicrobial resistance gene. The most prevalent multidrug-resistant (MDR) species were Enterobacter cloacae (8 isolates, 7.1%), Klebsiella pneumoniae (7 isolates, 6.3%), Klebsiella oxytoca (7 isolates, 6.3%), Escherichia coli (5 isolates, 4.5%), and Citrobacter freundii (3 isolates, 2.7%). The most commonly observed resistance phenotypes were against ampicillin (97.0%), streptomycin (94.1%), tetracycline (91.2%), trimethoprim-sulfamethoxazole (88.2%), nalidixic acid (85.3%), and chloramphenicol (76.5%). Class 1 integrons were detected in 28 (25.0%) isolates. The gene cassettes within class 1 integrons included those encoding resistance to trimethoprim (dfrA1, dfrA5, dfrA7, dfrA12, dfrA15, dfrA17, and dfrA25), aminoglycosides (aadA1, aadA2, aadA5, aadA7, aadA12, aadA22, and aac(3)-Id), chloramphenicol (cmlA), erythromycin (ereA2), and rifampicin (arr-3). Class 2 integrons were identified in 6 isolates (5.4%) with three different profiles. Furthermore, the β-lactamase encoding genes, bla(TEM), bla(SHV), bla(CTX-M), and bla(OXA), the plasmid-mediated quinolone resistance genes, qnr and aac(6)-Ib-cr, and the florfenicol resistance gene, floR, were also identified. To the best of our knowledge, the results identified class 2 integrons, qnr and aac(6)-Ib-cr from cases of mastitis for the first time. This is the first report of molecular characterization for antimicrobial resistance in Gram-negative bacteria isolated from bovine mastitis in Africa. | 2011 | 21338385 |
| 1112 | 5 | 0.9795 | Molecular Analysis of Antimicrobial Resistance among Enterobacteriaceae Isolated from Diarrhoeic Calves in Egypt. The present study was designed to investigate the presence of genes that conferred resistance to antimicrobials among Enterobacteriaceae that were isolated from diarrhoeic calves. A total of 120 faecal samples were collected from diarrhoeic calves that were raised in Kafr El-Sheikh governorate, Egypt. The samples were screened for Enterobacteriaceae. A total of 149 isolates of bacteria were recovered and identified; Escherichia coli was found to be the most overwhelming species, followed by Citrobacter diversus, Shigella spp., Serratia spp., Providencia spp., Enterobacter spp., Klebsiella pneumoniae, Proteus spp., Klebsiella oxytoca, and Morganella morganii. All isolates were tested for susceptibility to 12 antimicrobials; resistant and intermediately resistant strains were screened by conventional polymerase chain reaction for the presence of antimicrobial resistance genes. Of the 149 isolates, 37 (24.8%) exhibited multidrug resistant phenotypes. The most prevalent multidrug resistant species were E. coli, C. diversus, Serratia spp., K. pneumoniae, Shigella spp., Providencia spp., and K. oxytoca. Class 1 integrons were detected in 28 (18.8%) isolates. All isolates were negative for class 2 integrons. The bla(TEM) gene was identified in 37 (24.8%) isolates, whereas no isolates carried the bla(CTX-M) gene(.) The florfenicol gene (floR) was detected in two bacterial isolates (1.3%). The findings of this study reveal that calves may act as potential reservoirs of multidrug resistant bacteria that can be easily transmitted to humans. | 2021 | 34201226 |
| 1113 | 6 | 0.9795 | Prevalence of Colistin-Resistant Bacteria among Retail Meats in Japan. Colistin (CST) is considered the last resort for the treatment of infectious diseases due to multidrug-resistant bacteria. Since the mcr-1 gene has been reported in Enterobacteriaceae isolated from food, animals, and humans in China, the prevalence of CST-resistant bacteria has been of great concern. Here, we investigated the prevalence of CST resistance and plasmid-mediated colistin-resistance genes (mcr) in gram-negative bacteria isolated among retail meats in Japan. CST-resistant bacteria were isolated from 310 domestic retail meats (103 chicken meat, 103 pork, and 104 beef) purchased between May 2017 and July 2018 from retail shops in Japan using CST-containing media and antimicrobial susceptibility testing. The mcr gene was investigated in isolates with a CST minimum inhibitory concentration of ≥1 μg/mL. Excluding the intrinsically CST-resistant isolates, CST-resistant bacteria were isolated from 39 of the total chicken meats (37.9%), 19 of the pork samples (18.4%), and 18 of the beef samples (17.3%). A total of 459 isolates were identified, out of which 99 were CST-resistant. CST resistance (resistance breakpoints: Aeromonas, >4 μg/mL; others, >2 μg/mL) was found in Aeromonas spp. (48/206, 23.3%), Yersinia spp. (5/112, 4.5%), Escherichia coli (23/39, 59%), Citrobacter spp. (4/26, 15.4%), Klebsiella spp. (2/23, 8.7%), Raoultella spp. (2/16, 12.5%), Enterobacter spp. (7/14, 50%), Pseudomonas spp. (1/8, 12.5%), Pantoea spp. (5/7, 71.4%), Ewingella spp. (1/4, 25%), and Kluyvera spp. (1/2, 50%). The mcr gene was detected in 16 isolates: mcr-1 in 14 isolates of E. coli from 10 chicken samples (9.7%), and mcr-3 in two isolates of Aeromonas sobria from pork and chicken samples (each 1.0%). The findings of this study highlight the necessity of surveillance of CST resistance and resistance genes in bacteria that contaminate retail meats. | 2021 | 34249589 |
| 2996 | 7 | 0.9794 | Presence and antimicrobial resistance profiles of Escherichia coli, Enterococcusspp. and Salmonellasp. in 12 species of Australian shorebirds and terns. Antibiotic resistance is an ongoing threat to both human and animal health. Migratory birds are a potential vector for the spread of novel pathogens and antibiotic resistance genes. To date, there has been no comprehensive study investigating the presence of antibiotic resistance (AMR) in the bacteria of Australian shorebirds or terns. In the current study, 1022 individual birds representing 12 species were sampled across three states of Australia (Victoria, South Australia, and Western Australia) and tested for the presence of phenotypically resistant strains of three bacteria with potential to be zoonotic pathogens; Escherichia coli, Enterococcusspp., and Salmonellasp. In total, 206 E. coli, 266 Enterococcusspp., and 20 Salmonellasp. isolates were recovered, with AMR detected in 42% of E. coli, 85% of Enterococcusspp., and 10% of Salmonellasp. Phenotypic resistance was commonly detected to erythromycin (79% of Enterococcusspp.), ciprofloxacin (31% of Enterococcusspp.) and streptomycin (21% of E. coli). Resident birds were more likely to carry AMR bacteria than migratory birds (p ≤ .001). Bacteria isolated from shorebirds and terns are commonly resistant to at least one antibiotic, suggesting that wild bird populations serve as a potential reservoir and vector for AMR bacteria. However, globally emerging phenotypes of multidrug-resistant bacteria were not detected in Australian shorebirds. This study provides baseline data of the carriage of AMR bacteria in Australian shorebirds and terns. | 2022 | 35460193 |
| 1226 | 8 | 0.9794 | Multi-drug resistant gram-negative enteric bacteria isolated from flies at Chengdu Airport, China. We collected flies from Chengdu Shuangliu International Airport to examine for the presence of bacteria and to determine the sensitivity patterns of those bacteria. A total of 1,228 flies were collected from 6 sites around Chengdu Shuangliu International Airport from April to September 2011. The predominant species was Chrysomya megacephala (n=276, 22.5%). Antimicrobial-resistant gram-negative enteric bacteria (n=48) were isolated from flies using MacConkey agar supplemented with cephalothin (20 microg/ml). These were identified as Escherichia coli (n=37), Klebsiella pneumoniae (n=6), Pseudomonas aeruginosa (n=3) and Aeromonas hydrophila (n=2). All isolated bacteria were tested for resistance to 21 commonly used antimicrobials: amoxicillin (100%), ticarcillin (100%), cephalothin (100%), cefuroxime (100%), ceftazidime 1 (93.8%), piperacillin (93.8%), cefotaxime (89.6%), ticarcillin-clavulanate (81.3%), trimethoprim-sulfamethoxazole (62.5%), ciprofloxacin (54.2%), gentamicin (45.8%), cefepime (39.6%), tobramycin (39.6%), ceftazidime (22.9%), cefoxitin (16.7%), amikacin (16.7%), netilmicin (14.6%), amoxicillin-clavulanate (6.3%) and piperacillin-tazobactam (2.1%). No resistance to meropenem or imipenem was observed. Antibiotic resistance genes among the isolated bacteria were analyzed for by polymerase chain reaction. Thirty of the 48 bacteria with resistance (62.5%) possessed the blaTEM gene. | 2013 | 24450236 |
| 1167 | 9 | 0.9793 | Investigating the virulence-associated genes and antimicrobial resistance of Escherichia fergusonii Isolated from diseased ostrich chicks. This study investigates the presence of virulence-associated genes and antimicrobial resistance (AMR) in Escherichia fergusonii isolates obtained from ostrich chicks. A total of 287 isolates were recovered from 106 fecal samples from ostrich chicks suffering from diarrhea and subjected to molecular identification and biochemical characterization. E. fergusonii was detected in 10 samples (9.4 %) using two PCR-detection protocols. Notably, the isolates lacked various virulence genes commonly associated with pathogenic E. coli including elt, est, stx, eae, ehly, cdt, iss, iutA, iroN, hlyA, ompT, except for one isolate harboring the astA gene. Antimicrobial susceptibility testing revealed that all isolates were susceptible to ciprofloxacin, while high resistance was observed against amoxicillin clavulanate (AMC), trimethoprim-sulfamethoxazole (SXT), and doxycycline (D). Moreover, eight isolates displayed multidrug resistance (MDR) and four exhibited resistance to 9-11 antimicrobials. The most frequent resistance gene was sul2, which was present in all isolates; the other resistance genes detected consisted of int1 (4/10), int2 (3/10), bla(CMY) (2/10), and qnrS, bla(TEM), bla(CMY), bla(CTX-M), and flo each were detected only in one E. fergusonii Isolate. Plasmid replicon typing identified the presence of I1 (7/10), N (5/10), and Y (1/10). This study provides valuable insights into the virulence and antimicrobial resistance of E. fergusonii isolates from ostrich chicks, highlighting the complexity of antimicrobial resistance mechanisms exhibited by these bacteria. Further research is essential to understand the transmission dynamics and clinical implications of these findings in veterinary and public health settings. | 2024 | 39168034 |
| 1346 | 10 | 0.9793 | 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 |
| 1233 | 11 | 0.9792 | Prevalence, Antibiogram, and Resistance Profile of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates from Pig Farms in Luzon, Philippines. This cross-sectional study was conducted to determine the prevalence, antibiogram, and resistance profile of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) isolates from healthy pigs and pig farms in Luzon, Philippines. A total of 162 rectal samples from healthy finisher and breeder pigs and boot swab samples from pig houses were collected from 54 randomly selected pig farms. Bacteria were isolated and screened using MacConkey agar plate supplemented with 1 mg/L cefotaxime. Identification of bacteria and antimicrobial susceptibility test were carried out through Vitek(®) 2 and combined disk test. PCR amplifications were carried out in all isolates targeting bla(CTX-M) and its five major groupings, bla(TEM), and bla(SHV). The farm prevalence of ESBL-EC was 57.41% (95% confidence interval [CI] = 43.21-70.77). A total of 48 (29.63%) ESBL-EC isolates were isolated from samples that showed 14 different phenotypic multidrug resistance patterns. The prevalence of bla(CTX-M) gene was 91.67% (95% CI = 80.02-97.68). All major bla(CTX-M-groups) except bla(CTX-M-25group) were detected. The bla(CTX-M-1) was the most prevalent bla(CTX-M) gene, 75.0% (95% CI = 60.40-86.36). The prevalence of bla(TEM) and bla(SHV) genes was 91.67% (95% CI = 80.02-97.68) and 60.42% (95% CI = 45.27-74.23), respectively. Coexistence of different bla(CTX-M), bla(TEM), and bla(SHV) genes was observed in 44 isolates with 20 different genotypic patterns. High prevalence, diverse antibiogram profile, and genotypic resistance pattern of ESBL-EC isolates from healthy pigs and pig farms were observed in this study that could result in possible transmission to farm workers, susceptible bacteria, and the environment. | 2020 | 31532307 |
| 1253 | 12 | 0.9792 | 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 |
| 1364 | 13 | 0.9791 | Antimicrobial resistance patterns of Shiga toxin-producing Escherichia coli O157:H7 and O157:H7- from different origins. Shiga toxin-producing Escherichia coli (STEC) serotypes including O157:H7 (n = 129) from dairy cows, cull dairy cow feces, cider, salami, human feces, ground beef, bulk tank milk, bovine feces, and lettuce; and O157:H7- (n = 24) isolated from bovine dairy and bovine feedlot cows were evaluated for antimicrobial resistance against 26 antimicrobials and the presence of antimicrobial resistance genes (tetA, tetB, tetC, tetD, tetE, tetG, floR, cmlA, strA, strB, sulI, sulII, and ampC). All E. coli exhibited resistance to five or more antimicrobial agents, and the majority of isolates carried one or more target antimicrobial resistance gene(s) in different combinations. The majority of E. coli showed resistance to ampicillin, aztreonam, cefaclor, cephalothin, cinoxacin, and nalidixic acid, and all isolates were susceptible to chloramphenicol and florfenicol. Many STEC O157:H7 and O157:H7-isolates were susceptible to amikacin, carbenicillin, ceftriaxone, cefuroxime, ciprofloxacin, fosfomycin, moxalactam, norfloxacin, streptomycin, tobramycin, trimethoprim, and tetracycline. The majority of STEC O157:H7 (79.8%) and O157:H7- (91.7%) carried one or more antimicrobial resistance gene(s) regardless of whether phenotypically resistant or susceptible. Four tetracycline resistant STEC O157:H7 isolates carried both tetA and tetC. Other tetracycline resistance genes (tetB, tetD, tetE, and tetG) were not detected in any of the isolates. Among nine streptomycin resistant STEC O157:H7 isolates, eight carried strA-strB along with aadA, whereas the other isolate carried aadA alone. However, the majority of tetracycline and streptomycin susceptible STEC isolates also carried tetA and aadA genes, respectively. Most ampicillin resistant E. coli of both serotypes carried ampC genes. Among sulfonamide resistance genes, sulII was detected only in STEC O157:H7 (4 of 80 sulfonamide-resistant isolates) and sulI was detected in O157:H7- (1 of 16 sulfonamide resistant isolates). The emergence and dissemination of multidrug resistance in STEC can serve as a reservoir for different antimicrobial resistance genes. Dissemination of antimicrobial resistance genes to commensal and pathogenic bacteria could occur through any one of the horizontal gene transfer mechanisms adopted by the bacteria. | 2007 | 17536933 |
| 1221 | 14 | 0.9791 | Invasive whistling frogs (Eleutherodactylus johnstonei) act as a reservoir for antimicrobial-resistant Enterobacteriaceae in Latin America's most populous city. Invasive species represent a significant threat to ecological balance and the maintenance of native populations. Besides, these have been associated with the emergence of pathogens of public health importance, including multidrug-resistant bacteria. This study aimed to screen and describe the antimicrobial resistance profile of clinically important Enterobacteriaceae species isolated from whistling frogs (Eleutherodactylus johnstonei), an invasive anuran species in São Paulo, Brazil. Clinically relevant Enterobacteriaceae strains (n = 35) were isolated from oral and skin swabs of 19 whistling frogs and tested for antimicrobial susceptibility and antimicrobial resistance encoding genes. Resistance to amoxicillin + clavulanate and cefoxitin were the most frequent (16.67%; 4/24), followed by cefotaxime (5.71%; 2/35), ceftriaxone (2.86%; 1/35), and tetracycline (2.86%; 1/35). Among the antimicrobial resistance genes screened, bla(CTX-M group 8), bla(TEM), and bla(CMY) were identified. The whole genome of the bla(CTX-M group 8)-positive E. coli strain was assessed and confirmed bla(CTX-M-8) presence and phylogenetic analysis. Given the synanthropic behavior of whistling frogs, these amphibians may act as carriers of antimicrobial-resistant bacteria. | 2025 | 40884707 |
| 1389 | 15 | 0.9791 | Whole-Genome Sequencing of Gram-Negative Bacteria Isolated From Bovine Mastitis and Raw Milk: The First Emergence of Colistin mcr-10 and Fosfomycin fosA5 Resistance Genes in Klebsiella pneumoniae in Middle East. Antimicrobial resistance is a major concern in the dairy industry. This study investigated the prevalence, antimicrobial resistance phenotypes, and genome sequencing of Gram-negative bacteria isolated from clinical (n = 350) and subclinical (n = 95) bovine mastitis, and raw unpasteurized milk (n = 125). Klebsiella pneumoniae, Aeromonas hydrophila, Enterobacter cloacae (100% each), Escherichia coli (87.78%), and Proteus mirabilis (69.7%) were the most prevalent multidrug-resistant (MDR) species. Extensive drug-resistance (XDR) phenotype was found in P. mirabilis (30.30%) and E. coli (3.33%) isolates. Ten isolates (four E. coli, three Klebsiella species and three P. mirabilis) that displayed the highest multiple antibiotic resistance (MAR) indices (0.54-0.83), were exposed to whole-genome sequencing (WGS). Two multilocus sequence types (MLST): ST2165 and ST7624 were identified among the sequenced E. coli isolates. Three E. coli isolates (two from clinical mastitis and one from raw milk) belonging to ST2165 showed similar profile of plasmid replicon types: IncFIA, IncFIB, IncFII, and IncQ1 with an exception to an isolate that contained IncR, whereas E. coli ST7624 showed a different plasmid profile including IncHI2, IncHI2A, IncI1α, and IncFII replicon types. ResFinder findings revealed the presence of plasmid-mediated colistin mcr-10 and fosfomycin fosA5 resistance genes in a K. pneumoniae (K1) isolate from bovine milk. Sequence analysis of the reconstructed mcr-10 plasmid from WGS of K1 isolate, showed that mcr-10 gene was bracketed by xerC and insertion sequence IS26 on an IncFIB plasmid. Phylogenetic analysis revealed that K1 isolate existed in a clade including mcr-10-harboring isolates from human and environment with different STs and countries [United Kingdom (ST788), Australia (ST323), Malawi (ST2144), Myanmar (ST705), and Laos (ST2355)]. This study reports the first emergence of K. pneumoniae co-harboring mcr-10 and fosA5 genes from bovine milk in the Middle East, which constitutes a public health threat and heralds the penetration of the last-resort antibiotics. Hence, prudent use of antibiotics in both humans and animals and antimicrobial surveillance plans are urgently required. | 2021 | 34956131 |
| 1238 | 16 | 0.9790 | Lineages, Virulence Gene Associated and Integrons among Extended Spectrum β-Lactamase (ESBL) and CMY-2 Producing Enterobacteriaceae from Bovine Mastitis, in Tunisia. Extended Spectrum Beta-Lactamase (ESBL) Enterobacteriaceae are becoming widespread enzymes in food-producing animals worldwide. Escherichia coli and Klebseilla pneumoniae are two of the most significant pathogens causing mastitis. Our study focused on the characterization of the genetic support of ESBL/pAmpC and antibiotic resistance mechanisms in cefotaxime-resistant (CTXR) and susceptible (CTXS) Enterobacteriaceae isolates, recovered from bovine mastitis in Tunisia, as well as the analyses of their clonal lineage and virulence-associated genes. The study was carried out on 17 ESBL/pAmpC E. coli and K. pneumoniae and 50 CTXS E. coli. Detection of resistance genes and clonal diversity was performed by PCR amplification and sequencing. The following β-lactamase genes were detected: blaCTX-M-15 (n = 6), blaCTX-M-15 + blaOXA-1 (2), bla CTX-M-15 + blaOXA-1 + blaTEM-1b (2), blaCTX-M-15 + blaTEM-1b (4), blaCMY-2 (3). The MLST showed the following STs: ST405 (n = 4 strains); ST58 (n = 3); ST155 (n = 3); ST471 (n = 2); and ST101 (n = 2). ST399 (n = 1) and ST617 (n = 1) were identified in p(AmpC) E. coli producer strains. The phylogroups A and B1 were the most detected ones, followed by the pathogenic phylogroup B2 that harbored the shigatoxin genes stx1/stx2, associated with the cnf, fimA, and aer virulence factors. The qnrA/qnrB, aac(6′)-Ib-cr genes and integrons class 1 with different gene cassettes were detected amongst these CTXR/S isolated strains. The presence of different genetic lineages, associated with resistance and virulence genes in pathogenic bacteria in dairy farms, may complicate antibiotic therapies and pose a potential risk to public health. | 2022 | 36015067 |
| 2991 | 17 | 0.9790 | 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 |
| 1334 | 18 | 0.9789 | Intimin (eae) and virulence membrane protein pagC genes are associated with biofilm formation and multidrug resistance in Escherichia coli and Salmonella enterica isolates from calves with diarrhea. OBJECTIVES: This study aimed to evaluate the association of the intimin (eae) and pagC genes with biofilm formation and multidrug resistance (MDR) phenotype in Escherichia coli and Salmonella enterica collected from calves with diarrhea. RESULTS: Fecal samples (n: 150) were collected from calves with diarrhea. Of 150 fecal samples, 122 (81.3%) were culture positive and 115/122 (94.2%) were Gram-negative bacteria. Among them, E. coli (n = 64/115, 55.6%) was the most common isolate followed by S. enterica (n = 41/115, 35.6%). Also, 10 (8.6%) isolates were other Enterobacteriaceae bacteria including Klebsiella and Proteus species. Eighty-nine isolates (77.4%) from calf diarrhea, including 52 (81.3%) E. coli and 37 (90.2%) S. enterica were MDR. The eae and pagC genes were detected in 33 (51.5%) E. coli and 28 (68.3%) S. enterica isolates, respectively. There was a strong association between these genes and biofilm formation and MDR phenotype (P-value = 0.000). All E. coli isolates carrying the eae gene were biofilm producers and MDR. Also, all pagC-positive S. enterica isolates were MDR and 25 (89.3%) isolates of them produced biofilm. | 2022 | 36221149 |
| 948 | 19 | 0.9789 | Multidrug-Resistant Bacteria in Aquaculture Systems in Accra, Ghana. BACKGROUND: Antibiotic resistance (ABR) poses a critical global health challenge, necessitating its surveillance across both human and animal health sectors. This study evaluated ABR in bacteria harboured in reared inland fishes sold in Accra and the pond water from which they originated. METHOD: The study was cross-sectional, involving fishes and water sampled from 80 ponds. The gastrointestinal organs of the fishes were homogenised and cultured for bacteria, as were the water samples. The bacteria were identified using matrix-assisted laser desorption/ionisation time of flight mass spectrometry (MALDI-TOF-MS). Antimicrobial susceptibility test was done using the Kirby-Bauer method. Multidrug-resistant (MDR) bacteria were selected for further testing. The double disc diffusion method was used to detect extended-spectrum beta-lactamase (ESBL) production in isolates that were resistant to third-generation cephalosporins. Whole genome sequencing was performed on the ESBL-positive isolates using the Illumina Miseq platform. RESULTS: In total, 39 different bacterial species, with their individual numbers totalling 391, were isolated. The bacteria were predominantly Escherichia coli (17%), Aeromonas veronii (11%), Citrobacter freundii (8%), Bacillus cereus (5%), and Klebsiella pneumoniae (5%). The overall ABR rates were cefotaxime (32%), gentamicin (1%), ciprofloxacin (4%), chloramphenicol (19%), tetracycline (37%), meropenem (0%), and ertapenem (0%). Overall MDR and ESBL bacteria prevalence were 13.6% and 1.3%, respectively. The sequence types of the ESBL isolates were ST4684 (80%, n = 4) and ST2005 (20%, n = 1), and the serotypes were H34:09 (80%, n = 4) and H7 (20%, n = 1); the ABR genes were blaCTX-M-15, fosA7, and qnrS1. CONCLUSION: The fishes and the pond water were contaminated with a diverse range of bacteria, mainly Escherichia coli and Aeromonas veronii. The ABR, MDR, and ESBL rates were low to moderate. Moreover, the main sequence type and serotype of the ESBL isolates were ST4684 and H34:09, respectively, and the ABR genes were blaCTX-M-15, fosA7, and qnrS1. | 2024 | 39600552 |