Research Note: Detection of antibiotic-resistance genes in commercial poultry and turkey flocks from Italy. - Related Documents




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192901.0000Research Note: Detection of antibiotic-resistance genes in commercial poultry and turkey flocks from Italy. Antibiotics are routinely used in commercial poultry farms for the treatment of economically important bacterial diseases. Repeated use of antibiotics, usually administered in the feed or drinking water, may also result in the selection of resistant bacteria in animal feces, able to transfer their antimicrobial-resistance genes (ARG), residing on mobile elements, to other microorganisms, including human pathogens. In this study, single and multiplex PCR protocols were performed to detect tetracycline-, lincomycin-, chloramphenicol-, aminoglycoside-, colistin-, vancomycin-, and carbapenem-resistance genes, starting from 38 litter samples collected from 6 poultry and 2 turkey Italian flocks. The ARG were confirmed for all investigated classes of antimicrobials, except for colistin (mcr-1, mcr-2, mcr-3,mcr-4 mcr-5) and carbapenem (IMP, OXA-48, NDM, KPC), while the vanB gene was only detected for vancomycin. The highest positivity was obtained for tetracycline (tet[L], tet[M], tet[K], tetA[P]] and aminoglycoside (aadA2) ARG, confirming the predominant use of these antimicrobials in the veterinary practice and their potential to enhance the resistance patterns also in humans as a consequence of environmental contamination. On the contrary, the dissemination by poultry of ARG for critically important antimicrobials seems to be of minor concern, suggesting a negligible environmental dissemination by these genes in the Italian poultry industry. Finally, the molecular screening performed in this study using a noninvasive sampling method represents a simple and rapid tool for monitoring the ARG patterns at the farm level.202133799114
193510.9999Antibiotic Susceptibility Profile and Tetracycline Resistance Genes Detection in Salmonella spp. Strains Isolated from Animals and Food. Salmonella spp. is among the leading causes of foodborne infections in humans and a large number of animals. Salmonella spp. is a pathogen involved in the dissemination of antimicrobial resistance because it can accumulate antibiotic resistance genes (ARGs). In this study, the antibiotic resistance profile to 15 antibiotics, belonging to six different classes, of 60 strains of Salmonella spp. collected from pets, farm animals, wildlife, and food in Sicily (Italy) was investigated by the Kirby-Bauer method. Given that almost 33.3% of the Salmonella spp. strains were resistant to tetracycline, Real-Time PCR analysis was applied on all the 60 strains to detect the presence of eight selected tet resistance genes. Besides, the presence of the int1 gene, related to the horizontal gene transfer among bacteria, was also investigated in all the strains by Real-Time PCR analysis. Our data showed that 56% of the isolated strains harbored one or more tet resistance genes and that these strains were most frequently isolated from animals living in close contact with humans. Concerning int1, 17 strains (28.3%) harbored this genetic element and eight of these simultaneously contained tet genes. The results of this study highlight the importance of using a molecular approach to detect resistance genetic determinants, whose spread can increase the diffusion of multidrug-resistant strains. Besides, the study of zoonotic bacteria such as Salmonella spp. which significantly contribute to ARGs dissemination should always follow a One Health approach that considers the health of humans, animals, and the environment to be closely related.202134356729
193320.9999Antibiotic Resistance Genes Occurrence in Conventional and Antibiotic-Free Poultry Farming, Italy. Antimicrobial resistance is a complex and widespread problem threatening human and animal health. In poultry farms, a wide distribution of resistant bacteria and their relative genes is described worldwide, including in Italy. In this paper, a comparison of resistance gene distribution in litter samples, recovered from four conventional and four antibiotic-free broiler flocks, was performed to highlight any influence of farming systems on the spreading and maintenance of resistance determinants. Conventional PCR tests, targeting the resistance genes related to the most used antibiotics in poultry farming, along with some critically important antibiotics for human medicine, were applied. In conventional farms, n. 10 out of n. 30 investigated genes were present in at least one sample, the most abundant fragments being the tet genes specific for tetracyclines, followed by those for aminoglycosides and chloramphenicol. All conventional samples resulted negative for colistin, carbapenems, and vancomycin resistance genes. A similar trend was observed for antibiotic-free herds, with n. 13 out of n. 30 amplified genes, while a positivity for the mcr-1 gene, specific for colistin, was observed in one antibiotic-free flock. The statistical analysis revealed a significant difference for the tetM gene, which was found more frequently in the antibiotic-free category. The analysis carried out in this study allowed us to obtain new data about the distribution of resistance patterns in the poultry industry in relation to farming types. The PCR test is a quick and non-expensive laboratory tool for the environmental monitoring of resistance determinants identifying potential indicators of AMR dissemination.202236139170
192830.9999Targeted Antimicrobial Resistance Gene Screening from Metagenomic DNA of Raw Milk Samples Identifies the Presence of Multiple Genes Including the mcr9. The current study has investigated the prevalence of antimicrobial resistance (AMR) genes in cow and goat raw milk samples. The misuse of antibiotics in the livestock sector has already been reported to be a major factor contributing to AMR risk. For the study, milk samples were collected from five different farms, and metagenomic DNA was extracted. Then, PCR amplification was carried out using primers specific to 15 different AMR genes. From the results obtained, the prevalence of β-lactam resistance genes, particularly blaTEM (24%), along with other genes like blaZ (12%) and blaSHV (8%), were observed in addition to the transmissible mcr9 gene (12%) conferring resistance to colistin. These findings underscore the urgent need for monitoring AMR genes and regulating antibiotic use in dairy farming to safeguard public health, as it poses a potential risk with the consumption of unpasteurized milk.202540488653
193440.9999Sulfonamide resistance evaluation in five animal species and first report of sul4 in companion animals. Sulfonamides are one of the oldest groups of antibacterial agents with a broad-spectrum, used as first line treatment in bacterial infections. Their widespread use produced a selective pressure on bacteria, as observed by the high incidence of sulfonamides resistance mainly in Gram negative bacteria isolated from animals. In this research, the presence of sulfonamide resistance genes (sul1, sul2, sul3, and sul4) in phenotypically resistant Escherichia coli isolates has been studied. These genes were amplified in isolates recovered from five animal species, with different interactions to humans: cattle, swine, poultry as livestock, and dogs and cats as companion animals. Isolates were collected according to their phenotypic resistance, and the magnetic bead-based Luminex technology was applied to simultaneously detect sul target genes. The frequency of sul genes was highest in swine, among livestock isolates. The sul1 and sul2 were the most frequently sulfonamide resistance genes detected in all phenotypically resistant isolates. Notably, in companion animals, with a closest interaction with human, sul4 gene was detected. To our knowledge, this is the first report of the presence of sul4 gene in E. coli collected from animals, whereas previously the presence of this gene was reported in environmental, municipal wastewater and human clinical isolates. These results highlighted the importance of continuous antimicrobial resistant genes monitoring in animal species, with a special care to companion animals.202439029236
282050.9999Direct detection of antibiotic resistance genes in specimens of chicken and pork meat. Antibiotic resistance (AR) in bacteria, a major threat to human health, has emerged in the last few decades as a consequence of the selective pressure exerted by the widespread use of antibiotics in medicine, agriculture and veterinary practice and as growth promoters in animal husbandry. The frequency of 11 genes [tet(M), tet(O), tet(K), erm(A), erm(B), erm(C), vanA, vanB, aac (6')-Ie aph (2'')-Ia, mecA, blaZ] encoding resistance to some antibiotics widely used in clinical practice was analysed in raw pork and chicken meat and in fermented sausages as well as in faecal samples from the relevant farm animals using a molecular approach based on PCR amplification of bacterial DNA directly extracted from specimens. Some of the 11 AR genes were highly prevalent, the largest number being detected in chicken meat and pig faeces. The genes found most frequently in meat were tet(K) and erm(B); vanB and mecA were the least represented. All 11 determinants were detected in faecal samples except mecA, which was found only in chicken faeces. erm(B) and erm(C) were detected in all faecal samples. The frequency of AR genes was not appreciably different in meat compared to faecal specimens of the relevant animal except for vanB, which was more prevalent in faeces. Our findings suggest that AR genes are highly prevalent in food-associated bacteria and that AR contamination is likely related to breeding rather than processing techniques. Finally, the cultivation-independent molecular method used in this work to determine the prevalence of AR genes in foods proved to be a rapid and reliable alternative to traditional tools.200717005283
554560.9999Healthy broilers disseminate antibiotic resistance in response to tetracycline input in feed concentrates. Wide varieties of antibiotics are used in poultry farms to improve the growth and also to control the infection in broiler chicken. To identify the seriousness of the same in the poultry sector, current study has been designed to analyze the presence of tetracycline in poultry feed and also the tetracycline resistance among the bacteria released through the excreta of poultry. In the study, 27 bacteria belonging to the Escherichiacoli and Klebsiellapneumoniae. were isolated from the faecal samples collected from five different farms. Antibiotic susceptibility analysis showed 77% of E. coli and 100% of the K. pneumoniae. to be resistant to tetracycline. Further, molecular screening for tetA and tetB genes showed 85.18% of isolates to have tetA and 22.22% with tetB. The presence of tetracycline in collected feed samples was also analysed quantitatively by Liquid chromatography-mass spectrometry (LC-MS). Here, three out of five feed samples were found to be positive for tetracycline. The study showed a direct correlation between the antibiotic supplemented feed and the emergence of antimicrobial resistance among the intestinal microflora. The results of the study indicate the need for strict control over antibiotic use in animal feed to limit the rapid evolution and spread of antimicrobial resistance.202033039593
196770.9999Identification of molecular determinants of antibiotic resistance in some fish farms of Ghana. Antimicrobial resistance is a global health challenge caused by the ability of microorganisms including bacteria, fungi, protozoans and viruses to survive the effects of drugs that hitherto were effective against them. This study sought to investigate the presence of antibiotic-resistant bacteria and their corresponding molecular determinants in fish farms of the Central and Western Regions of Ghana. Management practices and antibiotic use at the fish farms were obtained through the administration of a questionnaire. Coliform and Gram-positive bacterial loads of catfish (Clarias gariepinus), tilapia (Oreochromis niloticus) intestinal microbiota, and pond water samples recovered on MacConkey Agar and Mannitol Salt Agar were determined. Bacterial isolates were identified using various biochemical assays. Antibiotic resistance profiles and possible responsible genes of bacterial isolates were determined using the disc diffusion and Polymerase Chain Reaction (PCR) methods respectively. The study revealed that none of the fish farm managers admitted using antibiotics for prevention and treatment of diseases and no major disease outbreak had ever been recorded. Bacterial loads of pond water exceeded the acceptable level of ≤100 E. coli and <10 coliforms per mL for wastewater recommended for use in fish farming. In all, 145 bacterial isolates comprising 99 Gram negative and 46 Gram-positive bacteria were stored and identified. Most isolates were resistant to at least an antibiotic. Both Gram-negative and Gram-positive bacteria were highly resistant to beta-lactam antibiotics with a corresponding high percentage detection of the bla (TEM) gene compared to other classes of antibiotics. This study has revealed the presence of various molecular determinants of antibiotic resistance including bla (TEM), cmIA, qnrS, tetB and bla (CTX-M), in multidrug-resistant bacteria at some fish farms in Ghana. There is the need to increase awareness about risks associated with the misuse and overuse of antibiotics by humans and the potential risk of spread of multi-drug resistant-bacteria in the environment.202236097488
194180.9999The association between antimicrobials and the antimicrobial-resistant phenotypes and resistance genes of Escherichia coli isolated from hospital wastewaters and adjacent surface waters in Sri Lanka. The presence of antimicrobials, antimicrobial-resistant bacteria (ARB), and the associated antimicrobial resistance genes (ARGs) in the environment is a global health concern. In this study, the concentrations of 25 antimicrobials, the resistance of Escherichia coli (E. coli) strains in response to the selection pressure imposed by 15 antimicrobials, and enrichment of 20 ARGs in E. coli isolated from hospital wastewaters and surface waters were investigated from 2016 to 2018. In hospital wastewaters, clarithromycin was detected at the highest concentration followed by sulfamethoxazole and sulfapyridine. Approximately 80% of the E. coli isolates were resistant, while 14% of the isolates exhibited intermediate resistance against the tested antimicrobial agents. Approximately 61% of the examined isolates were categorized as multidrug-resistant bacteria. The overall abundance of phenotypes that were resistant toward drugs was in the following order: β-lactams, tetracycline, quinolones, sulfamethoxazole/trimethoprim, aminoglycosides, and chloramphenicol. The data showed that the E. coli isolates frequently harbored bla(TEM), bla(CTX-M), tetA, qnrS, and sul2. These results indicated that personal care products were significantly associated with the presence of several resistant phenotypes and resistance genes, implying their role in co-association with multidrug resistance. Statistical analysis also indicated a disparity specific to the site, treatment, and year in the data describing the prevalence of ARB and ARGs and their release into downstream waters. This study provides novel insights into the abundance of antimicrobial, ARB and ARGs in Sri Lanka, and could further offer invaluable information that can be integrated into global antimicrobial resistance databases.202133894511
192690.9999Whole genome sequencing revealed high occurrence of antimicrobial resistance genes in bacteria isolated from poultry manure. BACKGROUND: Global demand for food has driven expansion and intensification of livestock production, particularly in developing nations where antibiotic use is often routine. Waste from poultry production, including manure, is commonly utilized as fertilizers in agroecosystems, risking environmental contamination with potentially zoonotic bacteria and antimicrobial resistance genes (ARGs). METHODS: Here, 33 bacterial isolates were recovered from broiler (n = 17) and layer (n = 16) chicken manure by aerobic culture using Luria Bertani agar. Antimicrobial susceptibility testing (AST) was performed using disc diffusion method. MALDI-ToF and 16S rRNA sequencing were used to identify and compare a subset of antibiotic-resistant isolates (n = 13). Comparison of whole genome sequence assemblies and phenotypic assays were used to assess capacity for biofilm formation, heavy metal tolerance and virulence. RESULTS: AST by disc diffusion revealed all isolates were resistant to a minimum of three antibiotics, with resistance to ampicillin, co-trimoxazole, fluoroquinolones, tetracyclines, streptomycin, rifampicin and/or chloramphenicol detected. Stutzerimonas sp. and Acinetobacter sp. were the common genera observed in this study. Genome sequencing of each selected isolate revealed carriage of multiple ARGs capable of conferring resistance to many antimicrobials commonly employed in poultry production and human medicine, including tetracyclines, quinolones, macrolides, sulfonamide and cephalosporins. CONCLUSIONS: The high occurrence of ARGs in studied bacterial isolates confirms that poultry manure could act as a source of genetic material that could be transferred to commensal microbiota and opportunistic pathogens of humans. Understanding the complex resistome interplay between humans, animals, and the environment requires a One Health approach, with implications for agricultural settings and public health.202539880102
2843100.9999High Throughput Screening of Antimicrobial Resistance Genes in Gram-Negative Seafood Bacteria. From a global view of antimicrobial resistance over different sectors, seafood and the marine environment are often considered as potential reservoirs of antimicrobial resistance genes (ARGs) and mobile genetic elements (MGEs); however, there are few studies and sparse results on this sector. This study aims to provide new data and insights regarding the content of resistance markers in various seafood samples and sources, and therefore the potential exposure to humans in a global One Health approach. An innovative high throughput qPCR screening was developed and validated in order to simultaneously investigate the presence of 41 ARGs and 33 MGEs including plasmid replicons, integrons, and insertion sequences in Gram-negative bacteria. Analysis of 268 seafood isolates from the bacterial microflora of cod (n = 24), shellfish (n = 66), flat fishes (n = 53), shrimp (n = 10), and horse mackerel (n = 115) show the occurrence of sul-1, ant(3″)-Ia, aph(3')-Ia, strA, strB, dfrA1, qnrA, and bla(CTX-M-9) genes in Pseudomonas spp., Providencia spp., Klebsiella spp., Proteus spp., and Shewanella spp. isolates and the presence of MGEs in all bacterial species investigated. We found that the occurrence of MGE may be associated with the seafood type and the environmental, farming, and harvest conditions. Moreover, even if MGE were detected in half of the seafood isolates investigated, association with ARG was only identified for twelve isolates. The results corroborate the hypothesis that the incidence of antimicrobial-resistant bacteria (ARB) and ARG decreases with increasing distance from potential sources of fecal contamination. This unique and original high throughput micro-array designed for the screening of ARG and MGE in Gram-negative bacteria could be easily implementable for monitoring antimicrobial resistance gene markers in diverse contexts.202235744743
1965110.9999Phenotypic Investigation of Florfenicol Resistance and Molecular Detection of floR Gene in Canine and Feline MDR Enterobacterales. Florfenicol is a promising antibiotic for use in companion animals, especially as an alternative agent for infections caused by MDR bacteria. However, the emergence of resistant strains could hinder this potential. In this study, florfenicol resistance was investigated in a total of 246 MDR Enterobacterales obtained from canine and feline clinical samples in Greece over a two-year period (October 2020 to December 2022); a total of 44 (17,9%) florfenicol-resistant strains were recognized and further investigated. Most of these isolates originated from urine (41.9%) and soft tissue (37.2%) samples; E. coli (n = 14) and Enterobacter cloacae (n = 12) were the predominant species. The strains were examined for the presence of specific florfenicol-related resistance genes floR and cfr. In the majority of the isolates (31/44, 70.5%), the floR gene was detected, whereas none carried cfr. This finding creates concerns of co-acquisition of plasmid-mediated florfenicol-specific ARGs through horizontal transfer, along with several other resistance genes. The florfenicol resistance rates in MDR isolates seem relatively low but considerable for a second-line antibiotic; thus, in order to evaluate the potential of florfenicol to constitute an alternative antibiotic in companion animals, continuous monitoring of antibiotic resistance profiles is needed in order to investigate the distribution of florfenicol resistance under pressure of administration of commonly used agents.202438393089
1927120.9999First Molecular Characterization and Antibiogram of Bacteria Isolated From Dairy Farm Wastewater in Bangladesh. This pioneering study in Bangladesh combines phenotypic and genotypic approaches to characterize antibiotic-resistant bacteria in dairy farm wastewater, addressing a critical gap in regional antimicrobial resistance (AMR) research. Dairy farming is integral to global food production, yet the wastewater generated by these operations is a significant source of environmental and public health concerns, particularly in the context of antibiotic resistance. This study aimed to isolate and identify antibiotic-resistant bacteria from dairy farm wastewater and evaluate their antibiogram profiles to inform effective management strategies. A total of 60 wastewater samples were collected and subjected to conventional bacterial characterization, followed by molecular detection via PCR and 16S rRNA gene sequencing. The study identified Pseudomonas aeruginosa (35%), Escherichia coli (30%), Bacillus subtilis (16.67%), and Acinetobacter junii (8.33%) as the predominant bacterial species. Sequencing results demonstrated high compatibility with reference sequences, confirming the identities of the isolates. Antibiogram analysis revealed significant resistance patterns: P. aeruginosa exhibited the highest resistance to penicillin (85.71%) and amoxicillin (76.19%), while demonstrating greater sensitivity to ciprofloxacin and cotrimoxazole. E. coli showed notable resistance to penicillin (88.89%), amoxicillin, and ceftriaxone, while B. subtilis and A. junii also demonstrated high levels of resistance to multiple antibiotics. Notably, a substantial proportion of the isolates exhibited multidrug resistance (MDR), with MAR indices ranging from 0.37 to 0.75. Moreover, several antibiotic resistance genes (ARGs) including penA, bla (TEM) , bla (CTX-M) , tetA, tetB, tetC, and ermB were detected across the bacterial species, with high prevalence rates in P. aeruginosa and A. junii, suggesting the potential for horizontal gene transfer and further spread of resistance. These findings underscore the critical need for a One Health approach to mitigate the risks posed by antibiotic-resistant bacteria in dairy farm wastewater, emphasizing the critical importance of responsible antibiotic use and sustainable farming practices to protect public health and environmental integrity.202540458482
1939130.9999Detection of microbial aerosols in hospital wards and molecular identification and dissemination of drug resistance of Escherichia coli. Antibiotic-resistant bacteria (ARB) present a global public health problem. Microorganisms are the main cause of hospital-acquired infections, and the biological contamination of hospital environments can cause the outbreak of a series of infectious diseases. Therefore, it is very important to understand the spread of antibiotic-resistant bacteria in hospital environments. This study examines the concentrations of aerobic bacteria and E. coli in ward environments and the airborne transmission of bacterial drug resistance. The results show that the three wards examined have an average aerobic bacterial concentration of 132 CFU∙m(-3) and an average inhalable aerobic bacterial concentration of 73 CFU∙m(-3), with no significant difference (P > 0.05) among the three wards. All isolated E. coli showed multi-drug resistance to not only third-generation cephalosporin antibiotics, but also quinolones, aminoglycosides, and sulfonamides. Furthermore, 51 airborne E. coli strains isolated from the air in the three wards and the corridor were screened for ESBLs, and 12 (23.53%) were ESBL-positive. The drug-resistance gene of the 12 ESBL-positive strains was mainly TEM gene, and the detection rate was 66.67% (8/12). According to a homology analysis with PFGE, 100% homologous E. coli from the ward at 5 m and 10 m outside the ward in the corridor shared the same drug-resistance spectrum, which further proves that airborne E. coli carrying a drug-resistance gene spreads out of the ward through gas exchange. This leads to biological pollution inside, outside, and around the ward, which poses a direct threat to the health of patients, healthcare workers, and surrounding residents. It is also the main reason for the antibiotic resistance in the hospital environment. More attention should be paid to comprehensive hygiene management in the surrounding environment of hospitals.202032070803
2734140.9999High Frequency of Antibiotic Resistance Genes (ARGs) in the Lerma River Basin, Mexico. The spread of beta-lactamase-producing bacteria is of great concern and the environment has been found to be a main source of contamination. Herein, it was proposed to determine the frequency of antimicrobial-resistant-Gram-negative bacteria throughout the Lerma River basin using phenotypic and molecular methods. Resistant bacteria were isolated with chromogenic media and antimicrobial susceptibility tests were used to characterize their resistance. ARGs for beta-lactams, aminoglycosides, and quinolones were detected by PCR. Species were identified by Sanger sequencing the 16S rRNA gene and the representative genomes of MDR strains were sequenced by NGS. A high variation in the number of isolates was observed in the 20 sampled sites, while observing a low diversity among the resistant bacteria. Of the 12 identified bacterial groups, C. freundii, E. coli, and S. marcescens were more predominant. A high frequency of resistance to beta-lactams, quinolones, and aminoglycosides was evidenced, where the bla(CTX,)qnrB, qnrS y, and aac(6')lb-cr genes were the most prevalent. C. freundii showed the highest frequency of MDR strains. Whole genome sequencing revealed that S. marcescens and K. pneumoniae showed a high number of shared virulence and antimicrobial resistance genes, while E. coli showed the highest number of unique genes. The contamination of the Lerma River with MDR strains carrying various ARGs should raise awareness among environmental authorities to assess the risks and regulations regarding the optimal hygienic and sanitary conditions for this important river that supports economic activities in the different communities in Mexico.202236360888
2844150.9999High throughput qPCR analyses suggest that Enterobacterales of French sheep and cow cheese rarely carry genes conferring resistances to critically important antibiotics for human medicine. Bacteria present in raw milk can carry acquired or intrinsic antimicrobial resistance genes (ARGs) and mobile genetic elements (MGEs). However, only a few studies have evaluated raw milk cheese as a potential reservoir of ARGs. This study thus aimed at providing new data regarding resistance markers present in raw milk cheese. Sheep (n = 360) and cow (n = 360) cheese samples produced in France were incubated in buffered peptone water supplemented with acriflavin or novobiocin; as corroborated by 16S metabarcoding, samples were enriched in Gram-negative bacteria since Escherichia coli and Hafnia alvei respectively accounted for 40 % and 20 % of the samples' microbiota. Screening of the samples for the presence of 30 ARGs and 16 MGEs by high throughput qPCR array showed that nine ARGs conferring resistances to 1st-generation beta-lactams, aminoglycosides, trimethoprim/sulfonamides and tetracyclines occurred in >75 % of both sheep and cow samples. This is neither surprising nor alarming since these resistance genes are widely spread across the One Health human, animal and environmental sectors. Conversely, genes conferring resistances to last-generations cephalosporins were rarely identified, while those conferring resistances to carbapenems or amikacin, which are restricted to human use, were never detected. Multiple MGEs were detected, the most frequent ones being IncF plasmids, confirming the potential transmission of ARGs. Our results are in line with the few studies of the resistome of milk or milk cheese showing that genes conferring resistances to 1st-generation beta-lactams, aminoglycosides and tetracyclines families are widespread, while those conferring resistances to critically important antibiotics are rare or absent.202337384974
2853160.9999Antibiotic resistance and virulence genes in coliform water isolates. Widespread fecal pollution of surface water may present a major health risk and a significant pathway for dissemination of antibiotic resistance bacteria. The River Rhine is one of the longest and most important rivers in Europe and an important raw water source for drinking water production. A total of 100 coliform isolates obtained from River Rhine (Germany) were examined for their susceptibility to seven antimicrobial agents. Resistances against amoxicillin, trimethoprim/sulfamethoxazole and tetracycline were detected in 48%, 11% and 9% of isolates respectively. The antibiotic resistance could be traced back to the resistance genes bla(TEM), bla(SHV), ampC, sul1, sul2, dfrA1, tet(A) and tet(B). Whereby, the ampC gene represents a special case, because its presence is not inevitably linked to a phenotypic antibiotic resistance. Multiple antibiotics resistance was often accompanied by the occurrence of class 1 or 2 integrons. E. coli isolates belonging to phylogenetic groups A and B1 (commensal) were more predominant (57%) compared to B2 and D groups (43%) which are known to carry virulent genes. Additionally, six E. coli virulence genes were also detected. However, the prevalence of virulence genes in the E. coli isolates was low (not exceeding 4.3% per gene) and no diarrheagenic E. coli pathotypes were detected. This study demonstrates that surface water is an important reservoir of ARGs for a number of antibiotic classes such as sulfonamide, trimethoprim, beta-lactam-antibiotics and tetracycline. The occurrence of antibiotic resistance in coliform bacteria isolated from River Rhine provides evidence for the need to develop management strategies to limit the spread of antibiotic resistant bacteria in aquatic environment.201627497615
5570170.9999Monitoring the Spread of Multidrug-Resistant Escherichia coli Throughout the Broiler Production Cycle. The extensive use of antimicrobials in broiler production is changing the bird microbiota, fostering drug-resistant bacteria, and complicating therapeutic interventions, making the problem of multidrug resistance global. The monitoring of antimicrobial virulence and resistance genes are tools that have come to assist the breeding of these animals, directing possible treatments as already used in human medicine and collecting data to demonstrate possible dissemination of multidrug-resistant strains that may cause damage to industry and public health. This work aimed to monitor broiler farms in southern Brazil, isolating samples of E. coli and classifying them according to the profile of resistance to antimicrobials of interest to human and animal health. We also monitored the profile of virulence genes and conducted an epidemiological survey of possible risk factors that contribute to this selection of multidrug-resistant isolates. Monitoring was carried out on farms in the three southern states of the country, collecting samples of poultry litter, cloacal swabs, and beetles of the species Alphitobius diaperinus, isolating E. coli from each of these samples. These were evaluated by testing their susceptibility to antimicrobials of animal and human interest; detecting whether the samples were extended-spectrum β-lactamase enzyme (ESBL) producers; and when positive, selected for genotypic tests to identify resistant genes (CTX-M, TEM, and SHV) and virulence. Among the antimicrobials tested, enrofloxacin and ciprofloxacin demonstrated some of the highest frequencies of resistance in the isolated strains, with significant statistical results. The use of these antimicrobials increased the likelihood of resistance by over three times and was associated with a 1.5-fold higher probability of multidrug resistance. Of all isolates, 95% were multidrug-resistant, raising concerns for production and public health. Among 231 ESBL-positive samples, the CTX-M1 group predominated.202539858355
2533180.9999Colistin Resistant mcr Genes Prevalence in Livestock Animals (Swine, Bovine, Poultry) from a Multinational Perspective. A Systematic Review. The objective of this review is to collect and present the results of relevant studies on an international level, on the subject of colistin resistance due to mcr genes prevalence in livestock animals. After a literature search, and using PRISMA guidelines principles, a total of 40 swine, 16 bovine and 31 poultry studies were collected concerning mcr-1 gene; five swine, three bovine and three poultry studies referred to mcr-2 gene; eight swine, one bovine, two poultry studies were about mcr-3 gene; six swine, one bovine and one poultry manuscript studied mcr-4 gene; five swine manuscripts studied mcr-5 gene; one swine manuscript was about mcr-6, mcr-7, mcr-8, mcr-9 genes and one poultry study about mcr-10 gene was found. Information about colistin resistance in bacteria derived from animals and animal product foods is still considered limited and that should be continually enhanced; most of the information about clinical isolates are relative to enteropathogens Escherichia coli and Salmonella spp. This review demonstrates the widespread dispersion of mcr genes to livestock animals, indicating the need to further increase measures to control this important threat for public health issue.202134822638
1948190.9999Identification and Characterization of Cefotaxime Resistant Bacteria in Beef Cattle. Third-generation cephalosporins are an important class of antibiotics that are widely used in treatment of serious Gram-negative bacterial infections. In this study, we report the isolation of bacteria resistant to the third-generation cephalosporin cefotaxime from cattle with no previous cefotaxime antibiotic exposure. The prevalence of cefotaxime-resistant bacteria was examined by a combination of culture based and molecular typing methods in beef cattle (n = 1341) from 8 herds located in North Central Florida. The overall prevalence of cefotaxime-resistant bacteria was 15.8% (95% CI: 13.9, 17.8), varied between farms, and ranged from 5.2% to 100%. A subset of isolates (n = 23) was further characterized for the cefotaxime minimum inhibitory concentration (MIC) and antibiotic susceptibility against 10 different antibiotics, sequencing of nine β- lactamase genes, and species identification by 16S rRNA sequencing. Most of the bacterial isolates were resistant to cefotaxime (concentrations, > 64 μg/mL) and showed high levels of multi-drug resistance. Full length 16S rRNA sequences (~1300 bp) revealed that most of the isolates were not primary human or animal pathogens; rather were more typical of commensal, soil, or other environmental origin. Six extended spectrum β-lactamase (ESBL) genes identical to those in clinical human isolates were identified. Our study highlights the potential for carriage of cefotaxime resistance (including "human" ESBL genes) by the bacterial flora of food animals with no history of cefotaxime antibiotic exposure. A better understanding of the origin and transmission of resistance genes in these pre-harvest settings will be critical to development of strategies to prevent the spread of antimicrobial resistant microorganisms to hospitals and communities.201627642751