# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 3157 | 0 | 0.9967 | Reservoirs of antimicrobial resistance genes in retail raw milk. BACKGROUND: It has been estimated that at least 3% of the USA population consumes unpasteurized (raw) milk from animal sources, and the demand to legalize raw milk sales continues to increase. However, consumption of raw milk can cause foodborne illness and be a source of bacteria containing transferrable antimicrobial resistance genes (ARGs). To obtain a comprehensive understanding of the microbiome and antibiotic resistome in both raw and processed milk, we systematically analyzed 2034 retail milk samples including unpasteurized milk and pasteurized milk via vat pasteurization, high-temperature-short-time pasteurization, and ultra-pasteurization from the United States using complementary culture-based, 16S rRNA gene, and metagenomic sequencing techniques. RESULTS: Raw milk samples had the highest prevalence of viable bacteria which were measured as all aerobic bacteria, coliform, and Escherichia coli counts, and their microbiota was distinct from other types of milk. 16S rRNA gene sequencing revealed that Pseudomonadaceae dominated raw milk with limited levels of lactic acid bacteria. Among all milk samples, the microbiota remained stable with constant bacterial populations when stored at 4 °C. In contrast, storage at room temperature dramatically enriched the bacterial populations present in raw milk samples and, in parallel, significantly increased the richness and abundance of ARGs. Metagenomic sequencing indicated raw milk possessed dramatically more ARGs than pasteurized milk, and a conjugation assay documented the active transfer of bla(CMY-2), one ceftazidime resistance gene present in raw milk-borne E. coli, across bacterial species. The room temperature-enriched resistome differed in raw milk from distinct geographic locations, a difference likely associated with regionally distinct milk microbiota. CONCLUSION: Despite advertised "probiotic" effects, our results indicate that raw milk microbiota has minimal lactic acid bacteria. In addition, retail raw milk serves as a reservoir of ARGs, populations of which are readily amplified by spontaneous fermentation. There is an increased need to understand potential food safety risks from improper transportation and storage of raw milk with regard to ARGs. Video Abstract. | 2020 | 32591006 |
| 6578 | 1 | 0.9967 | Contamination of Fresh Produce with Antibiotic-Resistant Bacteria and Associated Risks to Human Health: A Scoping Review. Fresh produce, when consumed raw, can be a source of exposure to antimicrobial residues, antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) of clinical importance. This review aims to determine: (1) the presence and abundance of antimicrobial residues, ARB and ARGs in fresh agricultural products sold in retail markets and consumed raw; (2) associated health risks in humans; and (3) pathways through which fresh produce becomes contaminated with ARB/ARGs. We searched the Ovid Medline, Web of Science and Hinari databases as well as grey literature, and identified 40 articles for inclusion. All studies investigated the occurrence of multidrug-resistant bacteria, and ten studies focused on ARGs in fresh produce, while none investigated antimicrobial residues. The most commonly observed ARB were E. coli (42.5%) followed by Klebsiella spp. (22.5%), and Salmonella spp. (20%), mainly detected on lettuce. Twenty-five articles mentioned health risks from consuming fresh produce but none quantified the risk. About half of the articles stated produce contamination occurred during pre- and post-harvest processes. Our review indicates that good agricultural and manufacturing practices, behavioural change communication and awareness-raising programs are required for all stakeholders along the food production and consumption supply chain to prevent ARB/ARG exposure through produce. | 2021 | 35010620 |
| 3204 | 2 | 0.9967 | Spread of airborne antibiotic resistance from animal farms to the environment: Dispersal pattern and exposure risk. Animal farms have been considered as the critical reservoir of antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB). Spread of antibiotic resistance from animal farms to the surrounding environments via aerosols has become a growing concern. Here we investigated the dispersal pattern and exposure risk of airborne ARGs (especially in zoonotic pathogens) in the environment of chicken and dairy farms. Aerosol, dust and animal feces samples were collected from the livestock houses and surrounding environments (upwind and downwind areas) for assessing ARG profiles. Antibiotic resistance phenotype and genotype of airborne Staphylococcus spp. was especially analyzed to reveal the exposure risk of airborne ARGs. Results showed that airborne ARGs were detected from upwind (50 m/100 m) and downwind (50 m/100 m/150 m) air environment, wherein at least 30% of bacterial taxa dispersed from the animal houses. Moreover, atmospheric dispersion modeling showed that airborne ARGs can disperse from the animal houses to a distance of 10 km along the wind direction. Clinically important pathogens were identified in airborne culturable bacteria. Genus of Staphylococcus, Sphingomonas and Acinetobacter were potential bacterial host of airborne ARGs. Airborne Staphylococcus spp. were isolated from the environment of chicken farm (n = 148) and dairy farm (n = 87). It is notable that all isolates from chicken-related environment were multidrug-resistance (>3 clinical-relevant antibiotics), with more than 80% of them carrying methicillin resistance gene (mecA) and associated ARGs and MGEs. Presence of numerous ARGs and diverse pathogens in dust from animal houses and the downwind residential areas indicated the accumulation of animal feces origin ARGs in bioaerosols. Employees and local residents in the chick farming environment are exposed to chicken originated ARGs and multidrug resistant Staphylococcus spp. via inhalation. This study highlights the potential exposure risks of airborne ARGs and antibiotic resistant pathogens to human health. | 2022 | 34673316 |
| 3162 | 3 | 0.9966 | Metagenomic Characterization of the Microbiome and Resistome of Retail Ground Beef Products. Ground beef can be a reservoir for a variety of bacteria, including spoilage organisms, and pathogenic foodborne bacteria. These bacteria can exhibit antimicrobial resistance (AMR) which is a public health concern if resistance in pathogens leads to treatment failure in humans. Culture-dependent techniques are commonly used to study individual bacterial species, but these techniques are unable to describe the whole community of microbial species (microbiome) and the profile of AMR genes they carry (resistome), which is critical for getting a holistic perspective of AMR. The objective of this study was to characterize the microbiome and resistome of retail ground beef products labeled as coming from conventional or raised without antibiotics (RWA) production systems. Sixteen ground beef products were purchased from 6 retail grocery outlets in Fort Collins, CO, half of which were labeled as produced from cattle raised conventionally and half of products were from RWA production. Total DNA was extracted and isolated from each sample and subjected to 16S rRNA amplicon sequencing for microbiome characterization and target-enriched shotgun sequencing to characterize the resistome. Differences in the microbiome and resistome of RWA and conventional ground beef were analyzed using the R programming software. Our results suggest that the resistome and microbiome of retail ground beef products with RWA packaging labels do not differ from products that do not carry claims regarding antimicrobial drug exposures during cattle production. The resistome predominantly consisted of tetracycline resistance making up more than 90% of reads mapped to resistance gene accessions in our samples. Firmicutes and Proteobacteria predominated in the microbiome of all samples (69.6% and 29.0%, respectively), but Proteobacteria composed a higher proportion in ground beef from conventionally raised cattle. In addition, our results suggest that product management, such as packaging type, could exert a stronger influence on the microbiome than the resistome in consumer-ready products. Metagenomic analyses of ground beef is a promising tool to investigate community-wide shifts in retail ground beef. Importantly, however, results from metagenomic sequencing must be carefully considered in parallel with traditional methods to better characterize the risk of AMR in retail products. | 2020 | 33240224 |
| 2583 | 4 | 0.9966 | From Farm to Slaughter: Tracing Antimicrobial Resistance in a Poultry Short Food Chain. Background: Short food supply chains are commonly perceived as more sustainable and safer alternatives to conventional production systems, often linked to organic, free-range livestock practices. Materials and methods: This study investigates, for the first time, the distribution of antimicrobial resistance genes (ARGs) and characterizes the microbial communities' composition, using 16S rRNA sequencing and real-time PCR, respectively. Eleven fecal, 76 slaughterhouse surface, 11 cecal, and 11 carcass samples, from 11 poultry farms belonging to the same short food chain, were analyzed in the study. Results: While cleaning and disinfection procedures appeared to reduce the bacterial load on slaughterhouse surfaces, diverse and potentially resistant bacteria, including genera such as Staphylococcus and Streptococcus, persisted both before and after slaughter. ARGs conferring resistance to high-priority critically important antimicrobials (HPCIAs), such as fluoroquinolones and third-generation cephalosporins, were frequently detected on carcasses, with qnrS (76.15%, 95%CI 68.02-84.28%) and bla(CMY2) (57.8%, 95%CI 48.38-67.22%) being the most prevalent. The slaughtering process emerged as a critical step for ARG dissemination via intestinal bacteria, such as genus Lactobacillus. Additionally, the detection of mcr genes and bla(NDM) on carcasses but not in the bird gut samples suggests possible anthropogenic contamination. Discussion: These findings highlight that the evisceration process, slaughterhouse environment, and personnel are all contributing factors in ARG spread and underscore the need for enhanced hygiene protocols and reduced gut ARG carriage in domestic birds to mitigate the risk for the consumer. | 2025 | 40558194 |
| 2557 | 5 | 0.9966 | Consumer Exposure to Antimicrobial Resistant Bacteria From Food at Swiss Retail Level. Background: Antimicrobial resistance (AMR) in bacteria is an increasing health concern. The spread of AMR bacteria (AMRB) between animals and humans via the food chain and the exchange of AMR genes requires holistic approaches for risk mitigation. The AMRB exposure of humans via food is currently only poorly understood leaving an important gap for intervention design. Method: This study aimed to assess AMRB prevalence in retail food and subsequent exposure of Swiss consumers in a systematic literature review of data published between 1996 and 2016 covering the Swiss agriculture sector and relevant imported food. Results: Data from 313 out of 9,473 collected studies were extracted yielding 122,438 food samples and 38,362 bacteria isolates of which 30,092 samples and 8,799 isolates were AMR positive. A median AMRB prevalence of >50% was observed for meat and seafood harboring Campylobacter, Enterococcus, Salmonella, Escherichia coli, Listeria, and Vibrio spp. and to a lesser prevalence for milk products harboring starter culture bacteria. Gram-negative AMRB featured predominantly AMR against aminoglycosides, cephalosporins, fluoroquinolones, penicillins, sulfonamides, and tetracyclines observed at AMR exposures scores of levels 1 (medium) and 2 (high) for Campylobacter, Salmonella, E. coli in meat as well as Vibrio and E. coli in seafood. Gram-positive AMRB featured AMR against glycoproteins, lincosamides, macrolides and nitrofurans for Staphylococcus and Enterococcus in meat sources, Staphylococcus in seafood as well as Enterococcus and technologically important bacteria (incl. starters) in fermented or processed dairy products. Knowledge gaps were identified for AMR prevalence in dairy, plant, fermented meat and novel food products and for the role of specific indicator bacteria (Staphylococcus, Enterococcus), starter culture bacteria and their mobile genetic elements in AMR gene transfer. Conclusion: Raw meat, milk, seafood, and certain fermented dairy products featured a medium to high potential of AMR exposure for Gram-negative and Gram-positive foodborne pathogens and indicator bacteria. Food at retail, additional food categories including fermented and novel foods as well as technologically important bacteria and AMR genetics are recommended to be better integrated into systematic One Health AMR surveillance and mitigation strategies to close observed knowledge gaps and enable a comprehensive AMR risk assessment for consumers. | 2018 | 29559960 |
| 2587 | 6 | 0.9966 | Prevalence of multi-drug resistant bacteria associated with foods and drinks in Nigeria (2015-2020): A systematic review. Foods are essential vehicles in human exposure to antibiotic resistant bacteria which serve as reservoirs for resistance genes and a rising food safety concern. Antimicrobial resistance, including multidrug resistance (MDR), is an increasing problem globally and poses a serious concern to human health. This study was designed to synthesize data regarding the prevalence of MDR bacteria associated with foods and drinks sold within Nigeria in order to contribute to the existing findings in this area. A comprehensive literature search on the prevalence of multi-drug resistant bacteria associated with foods and drinks in Nigeria from 2015 to 2020 was conducted using three databases; PubMed, Science Direct and Scopus. After screening and selection, 26 out of 82 articles were used for the qualitative data synthesis. Of the total of one thousand three hundred and twenty-six MDR bacteria reportedly isolated in all twenty-six articles, the highest prevalence (660) was observed in drinks, including water, while the lowest (20) was observed in the article which combined results for both protein and vegetable-based foods. Escherichia sp. had the most frequency of occurrence, appearing as MDR bacteria in ten out of the twenty-six articles. Salmonella sp. appeared as MDR in seven out of the twenty-six articles included in this study, in all seven articles where it was reported, it had the highest percentage (85.4%) prevalence as MDR bacteria. Public health personnel need to ensure critical control during the production and handling of foods and drinks, as well as create more awareness on proper hygienic practices to combat the spread of MDR bacteria becoming a growing food safety issue (Zurfluh et al., 2019; Mesbah et al., 2017; Campos et al., 2019). Foods can be contaminated by different means, including exposure to irrigation water, manure, feces or soil with pathogenic bacteria. Foods can also become contaminated as they are harvested, handled after harvest or during processing if food safety standards are not correctly applied (Meshbah et al., 2017). Food-borne diseases caused by resistant organisms are one of the most important public health problems as they contribute to the risk of development of antibiotic resistance in the food production chain (Hehempour-Baltork et al., 2019). Apart from pathogenic bacteria causing foodborne diseases, foods that are raw or not processed following standard procedures can introduce several antibiotic-resistant bacteria (ARB) to consumers (Gekemidis et al., 2018). Antibiotic resistance, though harbored in non-pathogenic bacteria, can potentially be spread through horizontal gene transfer to other species including opportunistic pathogens that are present in the environment or after consumption of ARB-contaminated foods. When ARB-contaminated foods are consumed, the spread of antibiotic resistant genes may affect the gut microbiome thereby contributing to the pool of antibiotic-resistance genes (ARG) in the human gut (Gekemidis et al, 2018). MDR bacteria have been defined as bacteria that are resistant to at least one antimicrobial agent present in three or more antimicrobial classes (Sweeny et al., 2018). There has been an increase in drug resistance in pathogens isolated from food for human consumption with species of Escherichia coli and Salmonella enterica being considered among the most important pathogens due to their ability to effect zoonotic transfer of resistant genes (Canton et al., 2018; Maneilla-Becerra et al., 2019). However, other pathogens, such as Vibrio spp., some species of Aeromonas, spores of Clostridium botulinum type F, and Campylobacter, have been linked to food-borne diseases in humans who have consumed seafood or other animal foods (Maneilla-Becerra et al., 2019). Some other resistant bacteria associated with foods include Staphylococcus aureus, Listeria spp., and Shigella spp. (Maneilla-Becerra et al., 2019) This study was therefore designed to synthesize data (2015-2020) regarding the prevalence of MDR bacteria associated with foods and drinks sold within Nigeria in order to contribute to the existing findings in this area. | 2021 | 35018289 |
| 5337 | 7 | 0.9965 | Swine waste: A reservoir of high-risk bla(NDM) and mcr-1. Multidrug resistance associated with pigs not only affects pig production but also threatens human health by influencing the farm surrounding and contaminating the food chain. This paper focused on the occurrence and prevalence of high-risk resistance genes (using bla(NDM) and mcr-1 as marker genes) in two Chinese swine farms, and investigated their fate and seasonal changes in piggery wastewater treatment systems (PWWTSs). Results revealed that bla(NDM) and mcr-1 were prevalent in both confined swine farms, and even prevailed through various processing stages of PWWTSs. Moreover, the abundance of bla(NDM) and mcr-1 in winter was higher than that in summer, with 0.01-1.01 logs variation in piggery wastewater. Of concern is that considerable amounts of bla(NDM) and mcr-1 were present in final effluent that is applied to farmland (up to 10(2)-10(4)copies/mL), raising the risk of propagation to indigenous bacteria. Worse still, those pig-derived isolates harboring the bla(NDM)/mcr-1 gene were confirmed to spread multidrug resistance to other bacteria, which further increased their dissemination potential in agricultural environment. This study highlights the prevalence of bla(NDM) and mcr-1 in swine farms, meanwhile, also emphasizes the necessary to mitigate the release and propagation of these high-risk genes from swine farms following land fertilization and wastewater usage. | 2019 | 31132710 |
| 7109 | 8 | 0.9965 | Explore the Contamination of Antibiotic Resistance Genes (ARGs) and Antibiotic-Resistant Bacteria (ARB) of the Processing Lines at Typical Broiler Slaughterhouse in China. Farms are a major source of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB), and previous research mainly focuses on polluted soils and breeding environments. However, slaughtering is an important link in the transmission of ARGs and ARB from farmland to dining table. In this study, we aim to reveal the pollution of ARGs and ARB in the slaughter process of broilers. First, by qualitative and quantitative analysis of ARGs in samples collected from the broiler slaughtering and processing production chain, the contamination level of ARGs was reflected; secondly, potential hosts for ARGs and microbial community were analyzed to reflect the possible transmission rules; thirdly, through the antibiotic susceptibility spectrum analysis of four typical food-borne pathogens, the distribution of ARB was revealed. The results showed that 24 types of ARGs were detected positive on the broiler slaughter production line, and tetracycline-resistance genes (20.45%) were the most frequently detected. The types of ARGs vary with sampling process, and all sampling links contain high levels of sul2 and intI1. The most abundant ARGs were detected in chicken surface in the scalding stage and entrails surface in the evisceration stage. There was a significant correlation between intI1 and tetM, suggesting that tetM might be able to enter the human food chain through class-1 integrons. The host range of the oqxB gene is the most extensive, including Sphingobacterium, Bacteroidia unclassified, Rothia, Microbacterium, Algoriella, etc. In the relevant links of the slaughter production line, the microbial community structure is similar. Removing viscera may cause diffusion of ARGs carried by intestinal microorganisms and contaminate chicken and following processing production. The four food-borne pathogens we tested are widely present in all aspects of the slaughter process, and most of them have multi-drug resistance and even have a high degree of resistance to some veterinary drugs banned by the Ministry of Agriculture. Our study preliminarily revealed the pollution of ARGs and ARB in the slaughter process of broilers, and these results are helpful to carry out food safety risk assessment and formulate corresponding control measures. | 2025 | 40232101 |
| 5285 | 9 | 0.9965 | Antibiotic Use in Beekeeping: Implications for Health and Environment from a One-Health Perspective. BACKGROUND: The use of antibiotics in beekeeping has potential implications for honeybee health and environmental contamination. Recent research indicates that extensive antibiotic use in beekeeping, especially oxytetracycline, promotes antimicrobial resistance in bee-related bacteria. Honeybees can transport oxytetracycline-resistance genes during foraging, potentially establishing reservoirs of resistance in the colony and facilitating intergeneric gene transfer among various gut bacteria as well as in the microbiome of the flowers and the wider environment, where honeybees can spread antibiotic-resistance genes over a large distance. This study investigates the effects of oxytetracycline hydrochloride (OTC) treatment on honeybees from a One Health perspective, examining antibiotic residues in honey, environmental spread, and the presence of tetracycline-resistance genes (TET-RGs). METHODS: In the spring of 2022, two groups of four honeybee hives were placed near an almond grove in Central Italy. One group was treated with 1.68 g of OTC, while the other remained untreated. Samples were collected from bees, honey, hive entrances, and flowers before treatment and at 3 as well as 9 days post-treatment. OTC residues and TET-RGs were analyzed to assess contamination and resistance gene dissemination. RESULTS: OTC residues were detected in honey from both treated (day 3: 263,250.0 ± 100,854.3 µg/kg; day 9: 132,600 ± 146,753.9 µg/kg) and untreated hives (day 3: 20.5 ± 8.2 µg/kg; day 9: 135.8 ± 198.6 µg/kg), suggesting cross-contamination. Residues were also found in almond tree flowers (0.7 ± 0.1 µg/kg), with TET-RGs (tet(K), tet(L), tet(M), tet(B), tet(O), tet(D)) detected pre- and post-treatment. In honeybee gut bacteria, resistance genes (tet(M), tet(A), tet(D), tet(B)) appeared post-treatment in both groups. No significant correlation was observed between hive distance and resistance gene presence in flowers, although the presence of other farms located within the bees' flight range, in which OTC might have been used in the past, could have influenced the results. CONCLUSIONS: These findings highlight the risk of OTC-induced antibiotic cross-contamination and the spread of TET-RG, raising concerns for bee health and environmental safety. Given honeybees' social nature and the negative effects of antibiotics on their health, an antibiotic-free management approach is recommended for sustainable apiculture. | 2025 | 40298498 |
| 5294 | 10 | 0.9965 | Association of florfenicol residues with the abundance of oxazolidinone resistance genes in livestock manures. Livestock and poultry manures are major reservoirs of antibiotic-resistant bacteria and antibiotic resistance genes (ARGs). Linezolid is a clinical medicine for humans and has never been approved for use in livestock. Interestingly, three linezolid resistance genes (cfr, optrA, and poxtA) have been detected in bacteria of animal origin, arousing public concern. This study investigated the abundance of three ARGs, cfr, optrA, and poxtA, in manures from 157 large-scale farms in China using real-time quantitative polymerase chain reaction. The residual concentrations of linezolid, florfenicol, tiamulin, and valnemulin were determined using ultra-high performance liquid chromatography-tandem mass spectrometry. A total of 140 livestock farms were tested positive for ARGs, and the positive detection rate was 89.17 %. OptrA was the most commonly detected ARG. The diversity and abundance of ARGs were significantly higher in poultry and swine manure than in bovine manure. Redundancy analysis presented a strong association between florfenicol and all the three ARGs targeted in the study, and tiamulin showed a significant correlation with optrA. Our results indicated that the residual concentration of florfenicol had a major effect on the distribution of the three ARGs in livestock manures, and extensive use of florfenicol may lead to the production of linezolid resistance genes. | 2020 | 32516648 |
| 3205 | 11 | 0.9965 | Determinants for antimicrobial resistance genes in farm dust on 333 poultry and pig farms in nine European countries. Livestock feces with antimicrobial resistant bacteria reaches the farm floor, manure pit, farm land and wider environment by run off and aerosolization. Little research has been done on the role of dust in the spread of antimicrobial resistance (AMR) in farms. Concentrations and potential determinants of antimicrobial resistance genes (ARGs) in farm dust are at present not known. Therefore in this study absolute ARG levels, representing the levels people and animals might be exposed to, and relative abundances of ARGs, representing the levels in the bacterial population, were quantified in airborne farm dust using qPCR. Four ARGs were determined in 947 freshly settled farm dust samples, captured with electrostatic dustfall collectors (EDCs), from 174 poultry (broiler) and 159 pig farms across nine European countries. By using linear mixed modeling, associations with fecal ARG levels, antimicrobial use (AMU) and farm and animal related parameters were determined. Results show similar relative abundances in farm dust as in feces and a significant positive association (ranging between 0.21 and 0.82) between the two reservoirs. AMU in pigs was positively associated with ARG abundances in dust from the same stable. Higher biosecurity standards were associated with lower relative ARG abundances in poultry and higher relative ARG abundances in pigs. Lower absolute ARG levels in dust were driven by, among others, summer season and certain bedding materials for poultry, and lower animal density and summer season for pigs. This study indicates different pathways that contribute to shaping the dust resistome in livestock farms, related to dust generation, or affecting the bacterial microbiome. Farm dust is a large reservoir of ARGs from which transmission to bacteria in other reservoirs can possibly occur. The identified determinants of ARG abundances in farm dust can guide future research and potentially farm management policy. | 2022 | 35033551 |
| 7110 | 12 | 0.9965 | The "best practices for farming" successfully contributed to decrease the antibiotic resistance gene abundances within dairy farms. INTRODUCTION: Farms are significant hotspots for the dissemination of antibiotic-resistant bacteria and genes (ARGs) into the environment and directly to humans. The prevalence of ARGs on farms underscores the need for effective strategies to reduce their spread. This study aimed to evaluate the impact of a guideline on "best practices for farming" aimed at reducing the dissemination of antibiotic resistance. METHODS: A guideline focused on prudent antibiotic use, selective therapy, and hygienic and immune-prophylactic practices was developed and provided to the owners of 10 selected dairy farms and their veterinarians. Fecal samples were collected from lactating cows, dry cows, and calves both before and after the implementation of the guideline. ARGs (bla (TEM), ermB, sul2, and tetA) were initially screened by end-point PCR, followed by quantification using digital droplet PCR. ARG abundance was expressed in relative terms by dividing the copy number of ARGs by the copy number of the 16S rRNA gene. RESULTS: The ARG abundances were higher in lactating cows compared to other categories. Despite similar levels of antibiotic administration (based on veterinary prescription data from the sampled farms) in both sampling campaigns, the total abundance of selected ARGs, particularly bla (TEM) and tetA, significantly decreased after the adoption of the farming guidelines. DISCUSSION: This study highlights the positive impact of prudent antibiotic use and the implementation of farming best practices in reducing the abundance of ARGs. The lactating cow category emerged as a crucial point of intervention for reducing the spread of antibiotic resistance. These findings contribute to ongoing efforts to address antibiotic resistance in farm environments and strengthen the evidence supporting the adoption of good farming practices. | 2024 | 39840338 |
| 3650 | 13 | 0.9965 | Molecular characterization of antimicrobial resistance genes on farms and in commercial milk with emphasis on the effect of currently practiced heat treatments on viable but nonculturable formation. Despite the considerable advances that have been made to improve dairy food safety, there is rising concern that pasteurization is not sufficient for the destruction of plasmid-mediated antimicrobial resistance (AMR) genes of resistant bacteria and could stimulate bacteria to enter into a viable but nonculturable (VBNC) state. In the current study, we surveyed the prevalence of 1 genomic and 9 plasmid-mediated AMR genes in 100 samples (bulk tank milk and milk filter socks) at the farm level and 152 commercial milk samples (pasteurized and UHT milks) and assessed the VBNC state in dairy bacteria. Results revealed that sul2 was the most prevalent plasmid-mediated gene in milk filter socks (96%), bulk tank milk (48%), pasteurized milk (68%), and UHT (43%) milk; in contrast, mecA was not detected in any sample. Additionally, commercial pasteurization (as currently practiced) failed to decrease the prevalence of the bla(TEM-B1) (43%), tetK (30%), and tetA (55%) plasmid-mediated AMR genes; thus, commercial pasteurization may be one of the factors creating the VBNC state in some dairy bacteria. Continued research is necessary to identify bacterial species entering the VBNC state after pasteurization, to assess their potential hazard level and shed more light on the expression and possibility of horizontal gene transfer of those plasmid-mediated AMR genes. | 2020 | 32861499 |
| 3099 | 14 | 0.9964 | Exploring bacterial diversity and antimicrobial resistance gene on a southern Brazilian swine farm. The bacterial composition of and the circulation of antimicrobial resistance genes (ARGs) in waste from Brazilian swine farms are still poorly understood. Considering that antimicrobial resistance (AMR) is one of the main threats to human, animal, and environmental health, the need to accurately assess the load of ARGs released into the environment is urgent. Therefore, this study aimed to characterize the microbiota in a swine farm in southern Brazil and the resistome in swine farm wastewater treated in a series of waste stabilization ponds (WSPs). Samples were collected from farm facilities and the surrounding environment, representing all levels of swine manure within the treatment system. Total metagenomic sequencing was performed on samples from WSPs, and 16S-rDNA sequencing was performed on all the collected samples. The results showed increased bacterial diversity in WSPs, characterized by the presence of Caldatribacteriota, Cloacimonadota, Desulfobacterota, Spirochaetota, Synergistota, and Verrucomicrobiota. Furthermore, resistance genes to tetracyclines, lincosamides, macrolides, rifamycin, phenicol, and genes conferring multidrug resistance were detected in WSPs samples. Interestingly, the most abundant ARG was linG, which confers resistance to the lincosamides. Notably, genes conferring macrolide (mphG and mefC) and rifamycin (rpoB_RIF) resistance appeared in greater numbers in the late WSPs. These drugs are among the high-priority antibiotic classes for human health. Moreover, certain mobile genetic elements (MGEs) were identified in the samples, notably tnpA, which was found in high abundance. These elements are of particular concern due to their potential to facilitate the dissemination of ARGs among bacteria. In summary, the results indicate that, in the studied farm, the swine manure treatment system could not eliminate ARGs and MGEs. Our results validate concerns about Brazil's swine production system. The misuse and overuse of antimicrobials during animal production must be avoided to mitigate AMR. | 2024 | 38740246 |
| 5705 | 15 | 0.9964 | Farming Practice Influences Antimicrobial Resistance Burden of Non-Aureus Staphylococci in Pig Husbandries. Non-aureus staphylococci (NAS) are ubiquitous bacteria in livestock-associated environments where they may act as reservoirs of antimicrobial resistance (AMR) genes for pathogens such as Staphylococcus aureus. Here, we tested whether housing conditions in pig farms could influence the overall AMR-NAS burden. Two hundred and forty porcine commensal and environmental NAS isolates from three different farm types (conventional, alternative, and organic) were tested for phenotypic antimicrobial susceptibility and subjected to whole genome sequencing. Genomic data were analysed regarding species identity and AMR gene carriage. Seventeen different NAS species were identified across all farm types. In contrast to conventional farms, no AMR genes were detectable towards methicillin, aminoglycosides, and phenicols in organic farms. Additionally, AMR genes to macrolides and tetracycline were rare among NAS in organic farms, while such genes were common in conventional husbandries. No differences in AMR detection existed between farm types regarding fosfomycin, lincosamides, fusidic acid, and heavy metal resistance gene presence. The combined data show that husbandry conditions influence the occurrence of resistant and multidrug-resistant bacteria in livestock, suggesting that changing husbandry practices may be an appropriate means of limiting the spread of AMR bacteria on farms. | 2022 | 36677324 |
| 3113 | 16 | 0.9964 | Resistome in the indoor dust samples from workplaces and households: a pilot study. The antibiotic resistance genes (ARGs) limit the susceptibility of bacteria to antimicrobials, representing a problem of high importance. Current research on the presence of ARGs in microorganisms focuses mainly on humans, livestock, hospitals, or wastewater. However, the spectrum of ARGs in the dust resistome in workplaces and households has gone relatively unexplored. This pilot study aimed to analyze resistome in indoor dust samples from participants' workplaces (a pediatric hospital, a maternity hospital, and a research center) and households and compare two different approaches to the ARGs analysis; high-throughput quantitative PCR (HT-qPCR) and whole metagenome shotgun sequencing (WMGS). In total, 143 ARGs were detected using HT-qPCR, with ARGs associated with the macrolides, lincosamides, and streptogramin B (MLSB) phenotype being the most abundant, followed by MDR (multi-drug resistance) genes, and genes conferring resistance to aminoglycosides. A higher overall relative quantity of ARGs was observed in indoor dust samples from workplaces than from households, with the pediatric hospital being associated with the highest relative quantity of ARGs. WMGS analysis revealed 36 ARGs, of which five were detected by both HT-qPCR and WMGS techniques. Accordingly, the efficacy of the WMGS approach to detect ARGs was lower than that of HT-qPCR. In summary, our pilot data revealed that indoor dust in buildings where people spend most of their time (workplaces, households) can be a significant source of antimicrobial-resistant microorganisms, which may potentially pose a health risk to both humans and animals. | 2024 | 39691696 |
| 5250 | 17 | 0.9964 | Antibiotic contamination and occurrence of antibiotic-resistant bacteria in aquatic environments of northern Vietnam. The ubiquitous application and release of antibiotics to the environment can result in bacterial antibiotic resistance, which in turn can be a serious risk to humans and other animals. Southeast Asian countries commonly apply an integrated recycling farm system called VAC (Vegetable, Aquaculture and Caged animal). In the VAC environment, antibiotics are released from animal and human origins, which would cause antibiotic-resistant bacteria (ARB). This study evaluated occurrence of ARB in the VAC environment in northern Vietnam, with quantitative analysis of antibiotic pollution. We found that sulfonamides were commonly detected at all sites. In dry season, while sulfamethazine was a major contaminant in pig farm pond (475-6662 ng/l) and less common in city canal and aquaculture sites, sulfamethoxazole was a major one in city canal (612-4330 ng/l). Erythromycin (154-2246 ng/l) and clarithromycin (2.8-778 ng/ml) were the common macrolides in city canal, but very low concentrations in pig farm pond and aquaculture sites. High frequencies of sulfamethoxazole-resistant bacteria (2.14-94.44%) were found whereas the occurrence rates of erythromycin-resistant bacteria were lower (<0.01-38.8%). A positive correlation was found between sulfamethoxazole concentration and occurrence of sulfamethoxazole-resistant bacteria in dry season. The sulfamethoxazole-resistant isolates were found to belong to 25 genera. Acinetobacter and Aeromonas were the major genera. Twenty three of 25 genera contained sul genes. This study showed specific contamination patterns in city and VAC environments and concluded that ARB occurred not only within contaminated sites but also those less contaminated. Various species can obtain resistance in VAC environment, which would be reservoir of drug resistance genes. Occurrence of ARB is suggested to relate with rainfall condition and horizontal gene transfer in diverse microbial community. | 2011 | 21669325 |
| 3208 | 18 | 0.9964 | Effects of Antibiotic Residues on Fecal Microbiota Composition and Antimicrobial Resistance Gene Profiles in Cattle from Northwestern China. Grazing is a free-range farming model commonly practiced in low-external-input agricultural systems. The widespread use of veterinary antibiotics in livestock farming has led to significant environmental accumulation of antibiotic residues and antibiotic resistance genes (ARGs), posing global health risks. This study investigated the antibiotic residues, bacterial community, ARG profiles, and mobile genetic elements (MGEs) in cattle feces from three provinces in western China (Ningxia, Xinjiang, and Inner Mongolia) under grazing modes. The HPLC-MS detection showed that the concentration of tetracycline antibiotics was the highest in all three provinces. Correlation analysis revealed a significant negative correlation between antibiotic residues and the diversity and population abundance of intestinal microbiota. However, the abundance of ARGs was directly proportional to antibiotic residues. Then, the Sankey analysis revealed that the ARGs in the cattle fecal samples were concentrated in 15 human pathogenic bacteria (HPB) species, with 9 of these species harboring multiple drug resistance genes. Metagenomic sequencing revealed that carbapenemase-resistant genes (bla(KPC) and bla(VIM)) were also present in considerable abundance, accounting for about 10% of the total ARGs detected in three provinces. Notably, Klebsiella pneumoniae strains carrying bla(CTX-M-55) were detected, which had a possibility of IncFII plasmids harboring transposons and IS19, indicating the risk of horizontal transfer of ARGs. This study significantly advances the understanding of the impact of antibiotic residues on the fecal microbiota composition and ARG profiles in grazing cattle from northwestern China. Furthermore, it provides critical insights for the development of rational antibiotic usage strategies and comprehensive public health risk assessments. | 2025 | 40732167 |
| 5364 | 19 | 0.9964 | Raw wastewater irrigation for urban agriculture in three African cities increases the abundance of transferable antibiotic resistance genes in soil, including those encoding extended spectrum β-lactamases (ESBLs). A study was conducted to investigate the impact of raw wastewater use for irrigation on dissemination of bacterial resistance in urban agriculture in African cities. The pollution of agricultural fields by selected antibiotic residues was assessed. The structure and functions of the soil microbial communities, presence of antibiotic resistance genes of human clinical importance and Enterobacteriaceae plasmid replicons were analysed using high throughput metagenomic sequencing. In irrigated fields, the richness of Bacteroidetes and Firmicutes phyla increased by 65% and 15.7%, respectively; functions allocated to microbial communities' adaptation and development increased by 3%. Abundance of antibiotic resistance genes of medical interest was 27% greater in irrigated fields. Extended spectrum β-lactamase genes identified in irrigated fields included bla(CARB-3), bla(OXA-347), bla(OXA-5) and bla(Rm3). The presence of ARGs encoding resistance to amphenicols, β-lactams, and tetracyclines were associated with the higher concentrations of ciprofloxacin, enrofloxacin and sulfamethoxazole in irrigated fields. Ten Enterobacteriaceae plasmid amplicon groups involved in the wide distribution of ARGs were identified in the fields. IncQ2, ColE, IncFIC, IncQ1, and IncFII were found in both farming systems; IncW and IncP1 in irrigated fields; and IncY, IncFIB and IncFIA in non-irrigated fields. In conclusion, raw wastewater irrigated soils in African cities could represent a vector for the spread of antibiotic resistance, thus threatening human and animal health. Consumers of products from these farms and farmers could be at risk of acquiring infections due to drug-resistant bacteria. | 2020 | 31505362 |