# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1345 | 0 | 0.9547 | Toxigenic potential and antimicrobial susceptibility of Bacillus cereus group bacteria isolated from Tunisian foodstuffs. BACKGROUND: Despite the importance of the B. cereus group as major foodborne pathogens that may cause diarrheal and/or emetic syndrome(s), no study in Tunisia has been conducted in order to characterize the pathogenic potential of the B. cereus group. The aim of this study was to assess the sanitary potential risks of 174 B. cereus group strains isolated from different foodstuffs by detecting and profiling virulence genes (hblA, hblB, hblC, hblD, nheA, nheB, nheC, cytK, bceT and ces), testing the isolates cytotoxic activity on Caco-2 cells and antimicrobial susceptibility towards 11 antibiotics. RESULTS: The entertoxin genes detected among B. cereus isolates were, in decreasing order, nheA (98.9%), nheC (97.7%) and nheB (86.8%) versus hblC (54.6%), hblD (54.6%), hblA (29.9%) and hblB (14.9%), respectively encoding for Non-hemolytic enterotoxin (NHE) and Hemolysin BL (HBL). The isolates are multi-toxigenic, harbouring at least one gene of each NHE and HBL complexes associated or not to bceT, cytK-2 and ces genes. Based on the incidence of virulence genes, the strains were separated into 12 toxigenic groups. Isolates positive for cytK (37,9%) harbored the cytK-2 variant. The detection rates of bceT and ces genes were 50.6 and 4%, respectively. When bacteria were incubated in BHI-YE at 30 °C for 18 h and for 5 d, 70.7 and 35% of the strains were shown to be cytotoxic to Caco-2 cells, respectively. The cytotoxicity of B. cereus strains depended on the food source of isolation. The presence of virulence factors is not always consistent with cytotoxicity. However, different combinations of enterotoxin genetic determinants are significantly associated to the cytotoxic potential of the bacteria. All strains were fully sensitive to rifampicin, chloramphenicol, ciprofloxacin, and gentamycin. The majority of the isolates were susceptible to streptomycin, kanamycin, erythromycin, vancomycin and tetracycline but showed resistance to ampicillin and novobiocin. CONCLUSION: Our results contribute data that are primary to facilitate risk assessments in order to prevent food poisoning due to B. cereus group. | 2019 | 31445510 |
| 1253 | 1 | 0.9545 | 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 |
| 1342 | 2 | 0.9542 | Prevalence, Toxin Genes, and Antibiotic Resistance Profiles of Bacillus cereus Isolates from Spices in Antalya and Isparta Provinces in Türkiye. Bacillus cereus is a pathogenic bacterium commonly found in nature and can produce toxins that cause food poisoning. This study aimed to detect the prevalence of B. cereus group bacteria in 50 unpackaged and 20 packaged spice samples frequently used as flavoring in Turkish cuisine, as well as investigate the presence of toxin genes and antibiotic resistance in the isolates. A total of 48 B. cereus group bacteria were isolated from 27 of 70 (38.57%) spice samples. The prevalence of B. cereus group bacteria in packaged (25%, 5/20) and unpackaged (44%, 22/50) spice samples did not differ significantly (P ˃ 0.05). All B. cereus group isolates were identified as B. cereus sensu stricto (B. cereus) using molecular methods. The hemolytic activity tests revealed that the most strains (44/48, 91.67%) are β-hemolytic. The distributions of toxin genes in isolates were investigated by PCR. It was determined that all isolates were identified to have 2-8 toxin genes, except B. cereus SBC3. The three most common toxin genes were found to be nheA (47/48, 97.92%), nheB (46/48, 95.83%), and entFM (46/48, 95.83%). All B. cereus isolates were susceptible to linezolid and vancomycin, while 35.42% (17/48) showed resistance to erythromycin. Multi-drug resistance (MDR) was detected in 8.3% (4/48) of B. cereus isolates, while 33.33% of the isolates showed multiple antibiotic resistance (MAR) index values higher than 0.2. The findings indicate that B. cereus may pose a health risk in packaged and unpackaged spices if present in high quantities. Therefore, the presence of B. cereus strains in both packaged and unpackaged spices should be monitored regarding consumer health and product safety. | 2023 | 38031610 |
| 1223 | 3 | 0.9534 | 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 |
| 1226 | 4 | 0.9532 | 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 |
| 1344 | 5 | 0.9531 | Antibiotics resistance and toxin profiles of Bacillus cereus-group isolates from fresh vegetables from German retail markets. BACKGROUND: This study aimed to evaluate the safety of raw vegetable products present on the German market regarding toxin-producing Bacillus cereus sensu lato (s.l.) group bacteria. RESULTS: A total of 147 B. cereus s.l. group strains isolated from cucumbers, carrots, herbs, salad leaves and ready-to-eat mixed salad leaves were analyzed. Their toxinogenic potential was assessed by multiplex PCR targeting the hemolysin BL (hbl) component D (hblD), non-hemolytic enterotoxin (nhe) component A (nheA), cytotoxin K-2 (cytK-2) and the cereulide (ces) toxin genes. In addition, a serological test was used to detect Hbl and Nhe toxins. On the basis of PCR and serological results, none of the strains were positive for the cereulide protein/genes, while 91.2, 83.0 and 37.4% were positive for the Hbl, Nhe and CytK toxins or their genes, respectively. Numerous strains produced multiple toxins. Generally, strains showed resistance against the β-lactam antibiotics such as penicillin G and cefotaxim (100%), as well as amoxicillin/clavulanic acid combination and ampicillin (99.3%). Most strains were susceptible to ciprofloxacin (99.3%), chloramphenicol (98.6%), amikacin (98.0%), imipenem (93.9%), erythromycin (91.8%), gentamicin (88.4%), tetracycline (76.2%) and trimethoprim/sulfamethoxazole combination (52.4%). The genomes of eight selected strains were sequenced. The toxin gene profiles detected by PCR and serological test mostly agreed with those from whole-genome sequence data. CONCLUSIONS: Our study showed that B. cereus s.l. strains encoding toxin genes occur in products sold on the German market and that these may pose a health risk to the consumer if present at elevated levels. Furthermore, a small percentage of these strains harbor antibiotic resistance genes. The presence of these bacteria in fresh produce should, therefore, be monitored to guarantee their safety. | 2019 | 31706266 |
| 1301 | 6 | 0.9527 | Phenotypic and Genotypic Assessment of Antibiotic Resistance of Staphylococcus aureus Bacteria Isolated from Retail Meat. BACKGROUND: Resistant Staphylococcus aureus (S. aureus) bacteria are determined to be one of the main causes of foodborne diseases. PURPOSE: This survey was done to assess the genotypic and phenotypic profiles of antibiotic resistance of S. aureus bacteria isolated from retail meat. METHODS: Four-hundred and eighty-five retail meat samples were collected and examined. S. aureus bacteria were identified using culture and biochemical tests. The phenotypic profile of antibiotic resistance was examined using the disk diffusion method. The genotypic pattern of antibiotic resistance was determined using the polymerase chain reaction. RESULTS: Forty-eight out of 485 (9.89%) raw retail meat samples were contaminated with S. aureus. Raw retail buffalo meat (16%) had the highest incidence of S. aureus, while raw camel meat (4%) had the lowest. S. aureus bacteria exhibited the uppermost incidence of resistance toward tetracycline (79.16%), penicillin (72.91%), gentamicin (60.41%), and doxycycline (41.666%). The incidence of resistance toward chloramphenicol (8.33%), levofloxacin (22.91%), rifampin (22.91%), and azithromycin (25%) was lower than other examined antibiotics. The most routinely detected antibiotic resistance genes were blaZ (58.33%), tetK (52.08%), aacA-D (33.33%), and ermA (27.08%). Cat1 (4.16%), rpoB (10.41%), msrA (12.50%), grlA (12.50%), linA (14.58%), and dfrA1 (16.66%) had the lower incidence rate. CONCLUSION: Raw meat of animals may be sources of resistant S. aureus which pose a hygienic threat about the consumption of raw meat. Nevertheless, further investigations are essential to understand supplementary epidemiological features of S. aureus in retail meat. | 2020 | 32440171 |
| 1258 | 7 | 0.9527 | 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 |
| 1302 | 8 | 0.9521 | 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 |
| 1294 | 9 | 0.9521 | Isolation and detection of antibiotics resistance genes of Escherichia coli from broiler farms in Sukabumi, Indonesia. OBJECTIVE: This study aimed to isolate and identify Escherichia coli from broiler samples from Sukabumi, Indonesia. Also, antibiogram studies of the isolated bacteria were carried out considering the detection of the antibiotic resistance genes. MATERIALS AND METHODS: Cloaca swabs (n = 45) were collected from broilers in Sukabumi, Indonesia. Isolation and identification of E. coli were carried out according to standard bacteriological techniques and biochemical tests, followed by confirmation of the polymerase chain reaction targeting the uspA gene. Antibiotic sensitivity test, using several antibiotics [tetracycline (TE), oxytetracycline (OT), ampicillin (AMP), gentamicin (CN), nalidixic acid (NA), ciprofloxacin (CIP), enrofloxacin (ENR), chloramphenicol, and erythromycin] was carried out following the Kirby-Bauer disk diffusion method. Detection of antibiotic resistance coding genes was carried out by PCR using specific oligonucleotide primers. Statistical analysis was carried out with one-way analysis of variance. RESULTS: The results showed that 55.6% (25/45) of the samples were associated with the presence of E. coli. Antibiotic sensitivity test showed that the E. coli isolates were resistant to TE (88%; 22/25), OT (88%; 22/25), AMP (100%; 25/25), CN (64%; 16/25), NA (100%; 22/25), CIP (88%; 22/25), ENR (72%; 18/25), chloramphenicol (0%; 0/25), and erythromycin (92%; 23/25). On the other hand, the antibiotic resistance coding genes were tetA (86.4%; 19/22), blaTEM (100%; 25/25), aac(3)-IV (0%; 0/16), gyrA (100%; 25/25), and ermB (13%; 3/23). It was found that chloramphenicol is markedly different from other antibiotic treatment groups. CONCLUSION: Escherichia coli was successfully isolated from cloacal swabs of broiler in Sukabumi, Indonesia. The bacteria were resistant to TE, OT, AMP, CN, NA, CIP, ENR, and erythromycin. Chloramphenicol was more sensitive and effective than other antibiotics in inhibiting the growth of E. coli. The antibiotic resistance genes detected were tetA, blaTEM, gyrA, and ermB. | 2021 | 33860017 |
| 1233 | 10 | 0.9520 | 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 |
| 1222 | 11 | 0.9520 | Molecular Characterization and the Antimicrobial Resistance Profile of Salmonella spp. Isolated from Ready-to-Eat Foods in Ouagadougou, Burkina Faso. The emergence of antimicrobial-resistantfood-borne bacteria is a great challenge to public health. This study was conducted to characterize and determine the resistance profile of Salmonella strains isolated from foods including sesames, ready-to-eat (RTE) salads, mango juices, and lettuce in Burkina Faso. One hundred and forty-eight biochemically identified Salmonella isolates were characterized by molecular amplification of Salmonella marker invA and spiC, misL, orfL, and pipD virulence genes. After that, all confirmed strains were examined for susceptibility to sixteen antimicrobials, and PCR amplifications were used to identify the following resistance genes: bla (TEM), temA, temB, StrA, aadA, sul1, sul2, tet(A), and tet(B). One hundred and eight isolates were genetically confirmed as Salmonella spp. Virulence genes were observed in 57.4%, 55.6%, 49.1%, and 38% isolates for pipD, SpiC, misL, and orfL, respectively. Isolates have shown moderate resistance to gentamycin (26.8%), ampicillin (22.2%), cefoxitin (19.4%), and nalidixic acid (18.5%). All isolates were sensitive to six antibiotics, including cefotaxime, ceftazidime, aztreonam, imipenem, meropenem, and ciprofloxacin. Among the 66 isolates resistant to at least one antibiotic, 11 (16.7%) were multidrug resistant. The Multiple Antimicrobial Resistance (MAR) index of Salmonella serovars ranged from 0.06 to 0.53. PCR detected 7 resistance genes (tet(A), tet(B), bla (TEM), temB, sul1, sul2, and aadA) in drug-resistant isolates. These findings raise serious concerns because ready-to-eat food in Burkina Faso could serve as a reservoir for spreading antimicrobial resistance genes worldwide. | 2022 | 36406904 |
| 1346 | 12 | 0.9515 | 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 |
| 1335 | 13 | 0.9514 | Prevalence of virulence factor, antibiotic resistance, and serotype genes of Pasteurella multocida strains isolated from pigs in Vietnam. AIM: The study was conducted to determine the prevalence and characterization of the Pasteurella multocida isolates from suspected pigs in Vietnam. MATERIALS AND METHODS: A total of 83 P. multocida strains were isolated from lung samples and nasal swabs collected from pigs associated with pneumonia, progressive atrophic rhinitis, or reproductive and respiratory symptoms. Isolates were subjected to multiplex polymerase chain reaction (PCR) for capsular typing, detection of virulence-associated genes and antibiotic resistance genes by PCR. The antimicrobial sensitivity profiles of the isolates were tested by disk diffusion method. RESULTS: All the isolates 83/83 (100%) were identified as P. multocida by PCR: serogroup A was obtained from 40/83 (48.19%), serogroup D was detected from 24/83 strains (28.91%), and serogroup B was found in 19/83 (22.35%) isolates. The presence of 14 virulence genes was reported including adhesins group (ptfA - 93.97%, pfhA - 93.97%, and fimA - 90.36%), iron acquisition (exbB - 100%, and exbD - 85.54%), hyaluronidase (pmHAS - 84.33%), and protectins (ompA - 56.62%, ompH 68.67%, and oma87 - 100%). The dermonecrotoxin toxA had low prevalence (19.28%). The antimicrobial susceptibility testing revealed that cephalexin, cefotaxime, ceftriaxone, ofloxacin, pefloxacin, ciprofloxacin, and enrofloxacin were the drugs most likely active against P. multocida while amoxicillin and tetracycline were inactive. The usage of PCR revealed that 63/83 isolates were carrying at least one of the drug resistance genes. CONCLUSION: Unlike other parts of the word, serotype B was prevalent among Vietnamese porcine P. multocida strains. The high antibiotic resistance detected among these isolates gives us an alert about the current state of imprudent antibiotic usage in controlling the pathogenic bacteria. | 2020 | 32636585 |
| 1254 | 14 | 0.9509 | Genetic diversity and antimicrobial resistance of Staphylococcus aureus from recurrent tonsillitis in children. The aim of this study was to analyze the prevalence of Staphylococcus aureus in the tonsils of children subjected tonsillectomy due to recurrent tonsilitis and to determine the spa types of the pathogens, carriage of virulence genes and antimicrobial resistance profiles. The study included 73 tonsillectomized children. Bacteria, including S. aureus were isolated from tonsillar surface prior to tonsillectomy, recovered from tonsillar core at the time of the surgery, and from posterior pharynx 2-4 weeks after the procedure. Staphylococcus aureus isolates were compared by spa typing, tested for antimicrobial susceptibility and for the presence of superantigenic toxin genes (sea-seu, eta, etb, tst, lukS/lukF-PV) by multiplex polymerase chain reaction. Seventy-three patients (mean 7.1 ± 4.1 years, 61.6% male) were assessed. The most commonly isolated bacteria were S. aureus. The largest proportion of staphylococcal isolates originated from tonsillar core (63%), followed by tonsillar surface (45.1%) and posterior pharynx in tonsillectomized children (18.2%, p = 0.007). Five (6.3%) isolates were identified as MRSA (mecA-positive). Up to 67.5% of the isolates synthesized penicillinases (blaZ-positive isolates), and 8.8% displayed MLS(B) resistance. The superantigenic toxin genes were detected in more than half of examined isolates (56.3%). spa types t091, t084, and t002, and clonal complexes (CCs) CC7, CC45, and CC30 turned out to be most common. Staphylococcus aureus associated with RT in children showed pathogenicity potential and considerable genetic diversity, and no clones were found to be specific for this condition although further studies are needed. | 2020 | 31692060 |
| 1295 | 15 | 0.9509 | Phenotypic and genotypic characterisation of antimicrobial resistance in faecal bacteria from 30 Giant pandas. To study the prevalence of antimicrobial resistance in faecal bacteria from Giant pandas in China, 59 isolates were recovered from faecal pats of 30 Giant pandas. Antimicrobial susceptibility testing of the isolates was performed by the standardised disk diffusion method (Kirby-Bauer). Of the 59 study isolates, 32.20% were resistant to at least one antimicrobial and 16.95% showed multidrug-resistant phenotypes. Thirteen drug resistance genes [aph(3')-IIa, aac(6')-Ib, ant(3'')-Ia, aac(3)-IIa, sul1, sul2, sul3, tetA, tetC, tetM, cat1, floR and cmlA] were analysed using four primer sets by multiplex polymerase chain reaction (PCR). The detection frequency of the aph(3')-IIa gene was the highest (10.17%), followed by cmlA (8.47%). The genes aac(6')-Ib, sul2 and tetA were not detected. PCR products were confirmed by DNA sequence analysis. The results revealed that multidrug resistance was widely present in bacteria isolated from Giant pandas. | 2009 | 19168331 |
| 1237 | 16 | 0.9508 | Characterization of Gene Families Encoding Beta-Lactamases of Gram-Negative Rods Isolated from Ready-to-Eat Vegetables in Mexico City. Beta-lactam resistant bacteria, which are commonly resident in tertiary hospitals, have emerged as a worldwide health problem because of ready-to-eat vegetable intake. We aimed to characterize the genes that provide resistance to beta-lactam antibiotics in Enterobacteriaceae, isolated from five commercial salad brands for human consumption in Mexico City. In total, twenty-five samples were collected, grown in blood agar plates, and the bacteria were biochemistry identified and antimicrobial susceptibility testing was done. The carried family genes were identified by endpoint PCR and the specific genes were confirmed with whole genome sequencing (WGS) by Next Generation Sequencing (NGS). Twelve positive cultures were identified and their microbiological distribution was as follows: 8.3% for Enterobacter aerogene (n = 1), 8.3% for Serratia fonticola (n = 1), 16.7% for Serratia marcesens (n = 2), 16.7% for Klebsiella pneumoniae (n = 2), and 50% (n = 6) for Enterobacter cloacae. The endpoint PCR results showed 11 colonies positive for blaBIL (91.7%), 11 for blaSHV (91.7%), 11 for blaCTX (97.7%), 12 for blaDHA (100%), four for blaVIM (33.3%), two for blaOXA (16.7%), two for blaIMP (16.7%), one for blaKPC (8.3%), and one for blaTEM (8.3%) gen; all samples were negative for blaROB, blaCMY, blaP, blaCFX and blaLAP gene. The sequencing analysis revealed a specific genotype for Enterobacter cloacae (blaSHV-12, blaCTX-M-15, blaDHA-1, blaKPC-2); Serratia marcescens (blaSHV-1, blaCTX-M-3, blaDHA-1, blaVIM-2); Klebsiella pneumoniae (blaSHV-12, blaCTX-M-15, blaDHA-1); Serratia fonticola (blaSHV-12, blaVIM-1, blaDHA-1); and, Enterobacter aerogene (blaSHV-1, blaCTX-M-1, blaDHA-1, blaVIM-2, blaOXA-9). Our results indicate that beta-lactam-resistant bacteria have acquired integrons with a different number of genes that provide pan-resistance to beta-lactam antibiotics, including penicillins, oxacillins, cefalosporins, monobactams, carbapenems, and imipenems. | 2018 | 30477153 |
| 1300 | 17 | 0.9508 | 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 |
| 1331 | 18 | 0.9507 | Serotypes, antibiotic resistance, and virulence genes of Salmonella in children with diarrhea. BACKGROUND: Salmonella is an important foodborne pathogen that causes acute diarrhea in humans worldwide. This study analyzed the relationships of serotypes and antibiotic resistance with virulence genes of Salmonella isolated from children with salmonellosis. METHODS: Serological typing was performed using the slide-agglutination method. The Kirby-Bauer disk diffusion method was used to test antibiotic susceptibility. Twenty virulence genes were detected by PCR. RESULTS: Salmonella Typhimurium (21 isolates, 34.43%) and S Enteritidis (12 isolates, 19.67%) were the predominant species among the 61 isolates. Ampicillin resistance was most common (63.93%), and among the cephalosporins, resistance was most often found to cefotaxime, a third-generation cephalosporin (19.67%). Among the 20 virulence genes, prgH, ssrB, and pagC were detected in all Salmonella isolates. In S Typhimurium, the detection rates of hilA, sipB, marT, mgtC, sopB, pagN, nlpI, bapA, oafA, and tolC were high. In S Enteritidis, the detection rates of icmF, spvB, spvR, and pefA were high. Nitrofurantoin resistance was negatively correlated with the virulence gene bapA (P = .005) and was positively correlated with icmF, spvB, spvR, and pefA (P = .012, .008, .002, and .005, respectively), The P values between all other virulence genes and antibiotic resistance were >.05. CONCLUSION: Salmonella Typhimurium and S Enteritidis were the main serotypes in children with diarrhea in Hangzhou, China. Salmonella exhibited a high level of resistance to common antibiotics, and a high rate of bacteria carrying virulence genes was observed. However, no significant correlation was found between virulence genes and resistance to common antibiotics. | 2020 | 32797660 |
| 1343 | 19 | 0.9506 | Profiling toxin genes and antibiotic resistance in Bacillus cereus isolated from pre-launch spacecraft. Characterization of the microbiomes of pre-launch spacecraft in spacecraft assembly facilities is an important step in keeping crews healthy during journeys that can last several hundred days in small artificial environments in space. Bacillus cereus, a foodborne pathogenic bacterium, has the potential to be a significant source of food contamination in such environments. This bacterium is a spore-forming bacteria that resists different antimicrobial treatments in cleanrooms where spacecraft are assembled. This study evaluated 41 B. cereus isolates from four pre-launch spacecraft in spacecraft assembly facilities for their toxin gene profile and antibiotic resistance. Four enterotoxin genes (hlbC, cytK, nheA, and entFM) and two emetic toxin genes (ces and CER) were targeted for chromosomal DNA and plasmid DNA. Results showed 31.7, 7.3, 85, and 41.5% of isolates contained hblC, cytK, nheA, and entFM, respectively, in chromosomal or plasmid DNA. Overall, 37 isolates (90.2%) showed at least one enterotoxin gene. The emetic toxin gene, ces, was detected in the plasmid DNA of three isolates (7.3%). The antibiotic resistance of isolates was evaluated by the Kirby-Bauer disk diffusion procedure. All the isolates exhibited 100% susceptibility to gentamicin, 97% were susceptible to clindamycin, and 95% to chloramphenicol, imipenem, tetracycline, and vancomycin. The overall susceptibility average is 51%. However, 98% of the isolates were resistant to β-lactam antibiotics, 97.5% were resistant to sulfamethoxazole/trimethoprim, and 80% were resistant to rifampin. This study provides important information on B. cereus isolates from spacecraft assembly facilities for use in microbial monitoring programs of spacecraft. | 2023 | 38045028 |