# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 7345 | 0 | 0.9963 | Multidrug-resistant bacteria and microbial communities in a river estuary with fragmented suburban waste management. River systems in developing and emerging countries are often fragmented relative to land and waste management in their catchment. The impact of inconsistent waste management and releases is a major challenge in water quality management. To examine how anthropogenic activities and estuarine effects impact water quality, we characterised water conditions, in-situ microbiomes, profiles of faecal pollution indicator, pathogenic and antibiotic resistant bacteria in the River Melayu, Southern Malaysia. Overall, upstream sampling locations were distinguished from those closer to the coastline by physicochemical parameters and bacterial communities. The abundances of bacterial DNA, total E. coli marker genes, culturable bacteria as well as antibiotic resistance ESBL-producing bacteria were elevated at upstream sampling locations especially near discharge of a wastewater oxidation pond. Furthermore, 85.7% of E. faecalis was multidrug-resistant (MDR), whereas 100% of E. cloacae, E. coli, K. pneumoniae were MDR. Overall, this work demonstrates how pollution in river estuaries does not monotonically change from inland towards the coast but varies according to local waste releases and tidal mixing. We also show that surrogate markers, such dissolved oxygen, Bacteroides and Prevotella abundances, and the rodA qPCR assay for total E. coli, can identify locations on a river that deserve immediate attention to mitigate AMR spread through improved waste management. | 2021 | 33301976 |
| 7077 | 1 | 0.9962 | Surfaces of gymnastic equipment as reservoirs of microbial pathogens with potential for transmission of bacterial infection and antimicrobial resistance. Gymnastic equipment surfaces are shared by many people, and could mediate the transfer of bacterial pathogens. To better understand this detrimental potential, investigations on the reservoirs of bacterial pathogens and antimicrobial resistance on the surfaces of gymnastic equipment were performed by analyzing the bacterial community structures, prevalence of viable bacteria, and presence of antimicrobial resistance on both indoor and outdoor gymnastic facilities. The results of high-throughput 16S rDNA amplicon sequencing showed that Gram-positive bacteria on the surfaces of indoor gymnastic equipment significantly enriched, including the opportunistic pathogen Staphylococcus strains, while Enterobacteriaceae significantly enriched on surfaces of outdoor gymnastic equipment. The analysis of α-diversities showed a higher richness and diversity for bacterial communities on the surfaces of gymnastic equipment than the environment. Analysis of β-diversities showed that the bacterial communities on the surfaces of gymnastic equipment differ significantly from environmental bacterial communities, while the bacterial communities on indoor and outdoor equipment are also significantly different. Thirty-four bacterial isolates were obtained from the surfaces of gymnastic equipment, including three multidrug Staphylococcus and one multidrug resistant Pantoea. In particular, Staphylococcus hemolyticus 5-6, isolated from the dumbbell surface, is a multidrug resistant, hemolytic, high- risk pathogen. The results of quantitative PCR targeting antibiotic resistance related genes (intI1, sul1 and bla (TEM)) showed that the abundances of sul1 and bla (TEM) genes on the surfaces of gymnastic equipment are higher than the environment, while the abundances of sul1 gene on indoor equipment are higher than outdoor equipment. These results lead to the conclusion that the surfaces of gymnastic equipment are potential dissemination pathways for highly dangerous pathogens as well as antimicrobial resistance, and the risks of indoor equipment are higher than outdoor equipment. | 2023 | 37152727 |
| 7080 | 2 | 0.9961 | Antibiotics, bacteria, and antibiotic resistance genes: aerial transport from cattle feed yards via particulate matter. BACKGROUND: Emergence and spread of antibiotic resistance has become a global health threat and is often linked with overuse and misuse of clinical and veterinary chemotherapeutic agents. Modern industrial-scale animal feeding operations rely extensively on veterinary pharmaceuticals, including antibiotics, to augment animal growth. Following excretion, antibiotics are transported through the environment via runoff, leaching, and land application of manure; however, airborne transport from feed yards has not been characterized. OBJECTIVES: The goal of this study was to determine the extent to which antibiotics, antibiotic resistance genes (ARG), and ruminant-associated microbes are aerially dispersed via particulate matter (PM) derived from large-scale beef cattle feed yards. METHODS: PM was collected downwind and upwind of 10 beef cattle feed yards. After extraction from PM, five veterinary antibiotics were quantified via high-performance liquid chromatography with tandem mass spectrometry, ARG were quantified via targeted quantitative polymerase chain reaction, and microbial community diversity was analyzed via 16S rRNA amplification and sequencing. RESULTS: Airborne PM derived from feed yards facilitated dispersal of several veterinary antibiotics, as well as microbial communities containing ARG. Concentrations of several antibiotics in airborne PM immediately downwind of feed yards ranged from 0.5 to 4.6 μg/g of PM. Microbial communities of PM collected downwind of feed yards were enriched with ruminant-associated taxa and were distinct when compared to upwind PM assemblages. Furthermore, genes encoding resistance to tetracycline antibiotics were significantly more abundant in PM collected downwind of feed yards as compared to upwind. CONCLUSIONS: Wind-dispersed PM from feed yards harbors antibiotics, bacteria, and ARGs. | 2015 | 25633846 |
| 3516 | 3 | 0.9960 | Presence of microplastic particles increased abundance of pathogens and antimicrobial resistance genes in microbial communities from the Oder river water and sediment. High abundance of microplastic particles (MPs) in the water environment could be a factor in spreading of pathogens and antimicrobial resistance genes (AMR), especially antibiotic resistance genes (ARGs). The aim of our study was to assess changes in the microbial community developing on microplastic surfaces incubated in water from the Oder River-one of Central Europe's major rivers, flowing through three countries (Czechia, Germany, and Poland)-whose diverse, 20,000-km(2) catchment area (encompassing industrial, agricultural, and urban regions) ensures a relatively high abundance of microbial communities.Samples of water and sediment were taken from river in Wroclaw area. Then the water was poured into disinfected glass liquid containers and pre-drained sediment was added. Control samples of water and sediment were collected on day 0. Then microplastic particles were added (500 mg; ~ 1 mm). Subsequent sampling was performed after incubation on 7(th) and 14(th) day. From each group, samples of sediment and water were collected after the incubation period (n = 5/group), for extraction of microbial DNA and library preparation. Sequencing was performed, using MinION sequencer with 10.4.1 Flow cell. Galaxy Europe platform and R program (v 4.3.3), alpha diversity and PERMANOVA with Benjamini-Hochberg p-value correction for multiple comparisons were used. For identification of biomarker taxa being different between groups, ANCOMBC (Analysis of Compositions of Microbiomes with Bias Correction) was performed. Obtained results shown higher abundance of pathogenic bacteria such as Aeromonas salmonicida Vibrio spp., Escherichia coli or Salmonella after 7 days of incubation in water and sediment. Additionally, after 7 days of incubation numbers of ARGs was higher compared to control group. | 2025 | 40348784 |
| 7133 | 4 | 0.9960 | Prevalence of antibiotic resistance genes in bacterial communities associated with Cladophora glomerata mats along the nearshore of Lake Ontario. The alga Cladophora glomerata can erupt in nuisance blooms throughout the lower Great Lakes. Since bacterial abundance increases with the emergence and decay of Cladophora, we investigated the prevalence of antibiotic resistance (ABR) in Cladophora-associated bacterial communities up-gradient and down-gradient from a large sewage treatment plant (STP) on Lake Ontario. Although STPs are well-known sources of ABR, we also expected detectable ABR from up-gradient wetland communities, since they receive surface run-off from urban and agricultural sources. Statistically significant differences in aquatic bacterial abundance and ABR were found between down-gradient beach samples and up-gradient coastal wetland samples (ANOVA, Holm-Sidak test, p < 0.05). Decaying and free-floating Cladophora sampled near the STP had the highest bacterial densities overall, including on ampicillin- and vancomycin-treated plates. However, quantitative polymerase chain reaction analysis of the ABR genes ampC, tetA, tetB, and vanA from environmental communities showed a different pattern. Some of the highest ABR gene levels occurred at the 2 coastal wetland sites (vanA). Overall, bacterial ABR profiles from environmental samples were distinguishable between living and decaying Cladophora, inferring that Cladophora may control bacterial ABR depending on its life-cycle stage. Our results also show how spatially and temporally dynamic ABR is in nearshore aquatic bacteria, which warrants further research. | 2017 | 28192677 |
| 2545 | 5 | 0.9959 | Environmental bacterial load during surgical and ultrasound procedures in a Swedish small animal hospital. BACKGROUND: Environmental bacteria in animal healthcare facilities may constitute a risk for healthcare-associated infections (HAI). Knowledge of the bacterial microflora composition and factors influencing the environmental bacterial load can support tailored interventions to lower the risk for HAI. The aims of this study were to: (1) quantify and identify environmental bacteria in one operating room (OR) and one ultrasound room (UR) in a small animal hospital, (2) compare the bacterial load to threshold values suggested for use in human healthcare facilities, (3) characterise the genetic relationship between selected bacterial species to assess clonal dissemination, and (4) investigate factors associated with bacterial load during surgery. Settle plates were used for passive air sampling and dip slides for surface sampling. Bacteria were identified by Matrix Assisted Laser Desorption-Time Of Flight. Antimicrobial susceptibility was determined by broth microdilution. Single nucleotide polymorphism-analysis was performed to identify genetically related isolates. Linear regression was performed to analyse associations between observed explanatory factors and bacterial load. RESULTS: The bacterial load on settle plates and dip slides were low both in the OR and the UR, most of the samples were below threshold values suggested for use in human healthcare facilities. All settle plates sampled during surgery were below the threshold values suggested for use in human clean surgical procedures. Staphylococcus spp. and Micrococcus spp. were the dominating species. There was no indication of clonal relationship among the sequenced isolates. Bacteria carrying genes conveying resistance to disinfectants were revealed. Air change and compliance with hygiene routines were sufficient in the OR. No other factors possibly associated with the bacterial load were identified. CONCLUSIONS: This study presents a generally low bacterial load in the studied OR and UR, indicating a low risk of transmission of infectious agents from the clinical environment. The results show that it is possible to achieve bacterial loads below threshold values suggested for use in human healthcare facilities in ORs in small animal hospitals and thus posing a reduced risk of HAI. Bacteria carrying genes conveying resistance to disinfectants indicates that resistant bacteria can persist in the clinical environment, with increased risk for HAI. | 2024 | 39223628 |
| 3077 | 6 | 0.9959 | The influence of urbanization and water reclamation plants on fecal indicator bacteria and antibiotic resistance in the Los Angeles River watershed: A case study with complementary monitoring methods. Urban land use and water reclamation plants (WRPs) can impact fecal indicator bacteria (FIB) and antimicrobial resistance (AMR) in coastal watersheds. However, there is a lack of studies exploring these effects on the US West Coast. Additionally, there is limited research using a complementary approach across culture-, qPCR-, and metagenomics-based techniques for characterizing environmental AMR. In this study, sixteen locations were sampled in the Los Angeles River, encompassing both upstream and downstream of three WRPs discharging into the river. Culture-dependent methods quantified Enterococcus, total coliforms, E. coli, and extended spectrum beta-lactamase-producing E. coli as a low-cost screening tool for AMR, while qPCR measured selected antibiotic resistance genes (ARGs): sul1, ermF, tetW, blaSHV, along with intI1 and 16S rRNA genes. Bacteroides HF183 and crAssphage markers were quantified via ddPCR. All samples underwent shotgun sequencing to investigate gene abundance and mobility and an overall risk score for AMR. Results reveal downstream sites contain ARGs at least two orders of magnitude greater than upstream locations. Developed areas had the highest ARG sequence abundances and the most ARG classes as indicated by metagenomic analysis. WRP effluent exhibited elevated ARGs and co-location of ARGs, mobile genetic elements, and pathogens. A culture-based assessment of AR in E. coli and Pseudomonas aeruginosa revealed increased resistance ratios for most antibiotics from upstream to downstream a WRP discharge point. This study highlights the impacts of land use and WRPs on ARGs and FIB, offering a multi-pronged analysis of AMR. | 2024 | 39566612 |
| 7086 | 7 | 0.9959 | Detection of faecal bacteria and antibiotic resistance genes in biofilms attached to plastics from human-impacted coastal areas. Plastics have been proposed as vectors of bacteria as they act as a substrate for biofilms. In this study, we evaluated the abundance of faecal and marine bacteria and antibiotic resistance genes (ARGs) from biofilms adhered to marine plastics. Floating plastics and plastics from sediments were collected in coastal areas impacted by human faecal pollution in the northwestern Mediterranean Sea. Culture and/or molecular methods were used to quantify faecal indicators (E. coli, Enterococci and crAssphage), and the ARGs sulI, tetW and bla(TEM) and the 16S rRNA were detected by qPCR assays. Pseudomonas and Vibrio species and heterotrophic marine bacteria were also analysed via culture-based methods. Results showed that, plastic particles covered by bacterial biofilms, primarily consisted of marine bacteria including Vibrio spp. Some floating plastics had a low concentration of viable E. coli and Enterococci (42% and 67% of the plastics respectively). Considering the median area of the plastics, we detected an average of 68 cfu E. coli per item, while a higher concentration of E. coli was detected on individual plastic items, when compared with 100 ml of the surrounding water. Using qPCR, we quantified higher values of faecal indicators which included inactive and dead microorganisms, detecting up to 2.6 × 10(2) gc mm(-2). The ARGs were detected in 67-88% of the floating plastics and in 29-57% of the sediment plastics with a concentration of up to 6.7 × 10(2) gc mm(-2). Furthermore, enrichment of these genes was observed in biofilms compared with the surrounding water. These results show that floating plastics act as a conduit for both the attachment and transport of faecal microorganisms. In contrast, low presence of faecal indicators was detected in plastic from seafloor sediments. Therefore, although in low concentrations, faecal bacteria, and potential pathogens, were identified in marine plastics, further suggesting plastics act as a reservoir of pathogens and ARGs. | 2023 | 36596379 |
| 7447 | 8 | 0.9959 | Holistic approach to chemical and microbiological quality of aquatic ecosystems impacted by wastewater effluent discharges. Wastewater treatment plants (WWTPs) collect wastewater from various sources and use different treatment processes to reduce the load of pollutants in the environment. Since the removal of many chemical pollutants and bacteria by WWTPs is incomplete, they constitute a potential source of contaminants. The continuous release of contaminants through WWTP effluents can compromise the health of the aquatic ecosystems, even if they occur at very low concentrations. The main objective of this work was to characterize, over a period of four months, the treatment steps starting from income to the effluent and 5 km downstream to the receiving river. In this context, the efficiency removal of chemical pollutants (e.g. hormones and pharmaceuticals, including antibiotics) and bacteria was assessed in a WWTP case study by using a holistic approach. It embraces different chemical and biological-based methods, such as pharmaceutical analysis by HPLC-MSMS, growth rate inhibition in algae, ligand binding estrogen receptor assay, microbial community study by 16S and shotgun sequencing along with relative quantification of resistance genes by quantitative polymerase chain reaction. Although both, chemical and biological-based methods showed a significant reduction of the pollutant burden in effluent and surface waters compared to the influent of the WWTP, no complete removal of pollutants, pathogens and antibiotic resistance genes was observed. | 2022 | 35489490 |
| 6574 | 9 | 0.9959 | Exploiting microplastics and the plastisphere for the surveillance of human pathogenic bacteria discharged into surface waters in wastewater effluent. Discharge from wastewater treatment plants (WWTPs) is a well-characterised source of human pathogens and antimicrobial resistance genes entering the environment. However, determining whether pathogens released from effluent into surface waters are viable, and consequently pose a risk to human health, is hindered by the use of transient grab-sampling monitoring approaches. Here we present a novel surveillance system using low-cost microparticles (polyethylene, cork and rubber) deployed upstream and downstream of a WWTP effluent pipe, that exploits the ability of bacterial pathogens to form biofilms. Using quantitative culture-based and molecular methods, viable E. coli, Klebsiella spp., Citrobacter spp., and Enterococcus spp. were identified after only 24-hour of deployment. Moreover, these pathogens were continually present at each timepoint (2, 4, 6, 8, 10, 14 and 23 days) as biofilm communities matured, with all pathogens detected at higher concentrations downstream of the WWTP effluent pipe. Long-read whole genome sequencing revealed a suite of plasmids, virulence genes and antimicrobial resistance genes in bacterial pathogens isolated from biofilms formed downstream of the effluent pipe. Furthermore, recognising that pathogens are typically present at proportionally low concentrations within mixed biofilm communities, total biofilm pathogenicity was confirmed using a Galleria mellonella infection model. Full-length 16S rRNA gene sequencing revealed that human pathogens present in microplastic biofilms (the 'plastisphere') dominated the microbial community of infected G. mellonella larvae within 24 hr, suggesting these bacteria remained highly virulent. Overall, this study demonstrated the efficacy of an easy-to-deploy system for the surveillance and rapid detection of pathogenic bacteria being discharged from point-source pollution. We envisage that if used as part of an integrated environmental management approach, this approach could help to reduce the public and environmental health risks of human pathogens and antimicrobial resistance genes, by monitoring viable human pathogens entering surface waters. | 2025 | 40184703 |
| 3289 | 10 | 0.9959 | Prevalence and seasonal dynamics of blaCTX-M antibiotic resistance genes and fecal indicator organisms in the lower Lahn River, Germany. Antibiotic-resistant bacteria represent an emerging global health problem and are frequently detected in riverine environments. Analyzing the occurrence of corresponding antibiotic-resistant genes in rivers is of public interest as it contributes towards understanding the origin and dissemination of these emerging microbial contaminants via surface water. This is critical for devising strategies to mitigate the spread of resistances in the environment. Concentrations of blaCTX-M antibiotic resistance genes were quantified weekly over a 12-month period in Lahn River surface water at two sampling sites using quantitative real-time PCR. Gene abundances were statistically assessed with regard to previously determined concentrations of fecal indicator organisms Escherichia coli, intestinal enterococci and somatic coliphages, as well as influential environmental factors. Similar seasonal patterns and strong positive correlations between fecal indicators and blaCTX-M genes indicated identical sources. Accordingly, linear regression analyses showed that blaCTX-M concentrations could largely be explained by fecal pollution. E. coli provided the best estimates (75% explained variance) at the upstream site, where proportions of blaCTX-M genes in relation to fecal indicator organisms were highest. At this site, rainfall proved to be more influential, hinting at surface runoff as an emission source. The level of agricultural impact increased from downstream to upstream, linking increasing blaCTX-M concentrations after rainfall events to the degree of agricultural land use. Exposure assessment revealed that even participants in non-swimming recreational activities were at risk of incidentally ingesting blaCTX-M genes and thus potentially antibiotic resistant bacteria. Considering that blaCTX-M genes are ubiquitous in Lahn River and participants in bathing and non-bathing water sports are at risk of exposure, results highlight the importance of microbial water quality monitoring with an emphasis on antibiotic resistance not only in designated bathing waters. Moreover, E. coli might serve as a suitable estimate for the presence of respective antibiotic resistant strains. | 2020 | 32353007 |
| 3075 | 11 | 0.9959 | Comparison of environmental microbiomes in an antibiotic resistance-polluted urban river highlights periphyton and fish gut communities as reservoirs of concern. Natural waterways near urban areas are heavily impacted by anthropogenic activities, including their microbial communities. A contaminant of growing public health concern in rivers is antibiotic resistant genes (ARGs), which can spread between neighboring bacteria and increase the potential for transmission of AR bacteria to animals and humans. To identify the matrices of most concern for AR, we compared ARG burdens and microbial community structures between sample types from the Scioto River Watershed, Ohio, the United States, from 2017 to 2018. Five environmental matrices (water, sediment, periphyton, detritus, and fish gut) were collected from 26 river sites. Due to our focus on clinically relevant ARGs, three carbapenem resistance genes (bla(KPC), bla(NDM), and bla(OXA-48)) were quantified via DropletDigital™ PCR. At a subset of nine urbanized sites, we conducted16S rRNA gene sequencing and functional gene predictions. Carbapenem resistance genes were quantified from all matrices, with bla(KPC) being the most detected (88 % of samples), followed by bla(NDM) (64 %) and bla(OXA-48) (23 %). Fish gut samples showed higher concentrations of bla(KPC) and bla(NDM) than any other matrix, indicating potential ARG bioaccumulation, and risk of broader dissemination through aquatic and nearshore food webs. Periphyton had higher concentrations of bla(NDM) than water, sediment, or detritus. Microbial community analysis identified differences by sample type in community diversity and structure. Sediment samples had the most diverse microbial communities, and detritus, the least. Spearman correlations did not reveal significant relationships between the concentrations of the monitored ARGs and microbial community diversity. However, several differentially abundant taxa and microbial functions were identified by sample type that is definitive of these matrices' roles in the river ecosystem and habitat type. In summary, the fish gut and periphyton are a concern as AR reservoirs due to their relatively high concentration of carbapenem resistance genes, diverse microbial communities, and natural functions that promote AR. | 2022 | 35973543 |
| 5308 | 12 | 0.9958 | Simultaneous stream assessment of antibiotics, bacteria, antibiotic resistant bacteria, and antibiotic resistance genes in an agricultural region of the United States. Antimicrobial resistance (AMR) is now recognized as a leading global threat to human health. Nevertheless, there currently is a limited understanding of the environment's role in the spread of AMR and antibiotic resistance genes (ARGs). In 2019, the U.S. Geological Survey conducted the first statewide assessment of antibiotic resistant bacteria (ARB) and ARGs in surface water and bed sediment collected from 34 stream locations across Iowa. Environmental samples were analyzed for a suite of 29 antibiotics and plated on selective media for 15 types of bacteria growth; DNA was extracted from culture growth and used in downstream polymerase chain reaction (PCR) assays for the detection of 24 ARGs. ARGs encoding resistance to antibiotics of clinical importance to human health and disease prevention were prioritized as their presence in stream systems has the potential for environmental significance. Total coliforms, Escherichia coli (E. coli), and staphylococci were nearly ubiquitous in both stream water and stream bed sediment samples, with enterococci present in 97 % of water samples, and Salmonella spp. growth present in 94 % and 67 % of water and bed sediment samples. Bacteria enumerations indicate that high bacteria loads are common in Iowa's streams, with 23 (68 %) streams exceeding state guidelines for primary contact for E. coli in recreational waters and 6 (18 %) streams exceeding the secondary contact advisory level. Although antibiotic-resistant E. coli growth was detected from 40 % of water samples, vancomycin-resistant enterococci (VRE) and penicillinase-resistant Staphylococcus aureus (MRSA) colony growth was detected from nearly all water samples. A total of 14 different ARGs were detected from viable bacteria cells from 30 Iowa streams (88 %, n = 34). Study results provide the first baseline understanding of the prevalence of ARB and ARGs throughout Iowa's waterways and health risk potential for humans, wildlife, and livestock using these waterways for drinking, irrigating, or recreating. | 2023 | 37673265 |
| 3069 | 13 | 0.9958 | The hospital sink drain biofilm resistome is independent of the corresponding microbiota, the environment and disinfection measures. In hospitals, the transmission of antibiotic-resistant bacteria (ARB) may occur via biofilms present in sink drains, which can lead to infections. Despite the potential role of sink drains in the transmission of ARB in nosocomial infections, routine surveillance of these drains is lacking in most hospitals. As a result, there is currently no comprehensive understanding of the transmission of ARB and the dissemination of antimicrobial resistance genes (ARGs) and associated mobile genetic elements (MGEs) via sink drains. This study employed a multifaceted approach to monitor the total aerobic bacteria as well as the presence of carbapenemase-producing Enterobacterales (CPEs), the microbiota and the resistome of sink drain biofilms (SDBs) and hospital wastewater (WW) of two separate intensive care units (ICUs) in the same healthcare facility in France. Samples of SDB and WW were collected on a monthly basis, from January to April 2023, in the neonatal (NICU) and the adult (AICU) ICUs of Grenoble Alpes University Hospital. In the NICU, sink drain disinfection with surfactants was performed routinely. In the AICU, routine disinfection is not carried out. Culturable aerobic bacteria were quantified on non-selective media, and CPEs were screened using two selective agars. Isolates were identified by MALDI-TOF MS, and antibiotic susceptibility testing (AST) was performed on Enterobacterales and P. aeruginosa. The resistome was analyzed by high-throughput qPCR targeting >80 ARGs and MGEs. The overall bacterial microbiota was assessed via full-length 16S rRNA sequencing. No CPEs were isolated from SDBs in either ICU by bacterial culture. Culture-independent approaches revealed an overall distinct microbiota composition of the SDBs in the two ICUs. The AICU SDBs were dominated by pathogens containing Gram-negative bacterial genera including Pseudomonas, Stenotrophomona, Klebsiella, and Gram-positive Staphylococcus, while the NICU SDBs were dominated by the Gram-negative genera Achromobacter, Serratia, and Acidovorax, as well as the Gram-positive genera Weisella and Lactiplantibacillus. In contrast, the resistome of the SDBs exhibited no significant differences between the two ICUs, indicating that the abundance of ARGs and MGEs is independent of microbiota composition and disinfection practices. The AICU WW exhibited more distinct aerobic bacteria than the NICU WW. In addition, the AICU WW yielded 15 CPEs, whereas the NICU WW yielded a single CPE. All the CPEs were characterized at the species level. The microbiota of the NICU and AICU WW samples differed from their respective SDBs and exhibited distinct variations over the four-month period:the AICU WW contained a greater number of genes conferring resistance to quinolones and integron integrase genes, whereas the NICU WW exhibited a higher abundance of streptogramin resistance genes. Our study demonstrated that the resistome of the hospital SDBs in the two ICUs of the investigated healthcare institute is independent of the microbiota, the environment, and the local disinfection measures. However, the prevalence of CPEs in the WW pipes collecting the waste from the investigated drains differed. These findings offer valuable insights into the resilience of resistance genes in SDBs in ICUs, underscoring the necessity for innovative strategies to combat antimicrobial resistance in clinical environments. | 2025 | 40483807 |
| 3191 | 14 | 0.9958 | Profiling of Bacterial Communities of Hospital Wastewater Reveals Clinically Relevant Genera and Antimicrobial Resistance Genes. In Mexico, hospital wastewater (HWW) is a source of chemical and microbiological contamination, and it is released into the municipal sewage system without prior treatment. This water may contain pathogenic bacteria and antimicrobial resistance genes, which represent a risk to Public Health and the environment. So far, there are no studies that analyse this problem comprehensively, relating bacterial population structures, chemical contaminants, and seasonality. The aim of this work was to seasonally characterise the bacterial communities of HWW, including clinically relevant bacteria and resistance genes in Hospital Juárez de México (HJM), and to evaluate the impact of physicochemical factors on their composition. A one-year observational, cross-sectional study was conducted at five HWW discharge points of HJM. Fourteen physicochemical parameters were determined by using standard methodologies, and statistical differences between discharges and seasons were evaluated. Bacterial communities were analysed by targeted amplicon sequencing of the V3-V4 region of the 16S rRNA gene. In addition, the presence of eight antimicrobial resistance genes of local epidemiological importance was assessed. Data were analysed using alpha and beta diversity indices, principal component analysis, and multivariate statistical tests. HWW showed high taxonomic diversity, with Proteobacteria, Firmicutes, and Bacteroidetes standing out. Clinically relevant bacteria were identified in 73.3% of the analyses, with Enterobacter and Escherichia-Shigella predominating. Total and dissolved solids, temperature, nitrate, and pH significantly influenced the bacterial composition of HWW. Seven out of the eight genes evaluated were identified, with bla(KPC), bla(OXA-40), and mcr-1 being the most frequent, showing significant seasonal differences. This study underlines the microbiological and chemical complexity of HWW, highlighting the impact of clinically relevant bacteria and antimicrobial resistance genes on Public Health. The findings emphasise the need to implement hospital waste management programmes and ideally specific treatment plants to minimise the associated risks and protect the environment and human health. | 2025 | 40572204 |
| 3624 | 15 | 0.9958 | Occurrence of multi-antibiotic resistant Pseudomonas spp. in drinking water produced from karstic hydrosystems. Aquatic environments could play a role in the spread of antibiotic resistance genes by enabling antibiotic-resistant bacteria transferred through wastewater inputs to connect with autochthonous bacteria. Consequently, drinking water could be a potential pathway to humans and animals for antibiotic resistance genes. The aim of this study was to investigate occurrences of Escherichia coli and Pseudomonas spp. in drinking water produced from a karst, a vulnerable aquifer with frequent increases in water turbidity after rainfall events and run-offs. Water samples were collected throughout the system from the karstic springs to the drinking water tap during three non-turbid periods and two turbid events. E. coli densities in the springs were 10- to 1000-fold higher during the turbid events than during the non-turbid periods, indicating that, with increased turbidity, surface water had entered the karstic system and contaminated the spring water. However, no E. coli were isolated in the drinking water. In contrast, Pseudomonas spp. were isolated from the drinking water only during turbid events, while the densities in the springs were from 10- to 100-fold higher than in the non-turbid periods. All the 580 Pseudomonas spp. isolates obtained from the sampling periods were resistant (to between 1 and 10 antibiotics), with similar resistance patterns. Among all the Pseudomonas isolated throughout the drinking water production system, between 32% and 86% carried the major resistance pattern: ticarcillin, ticarcillin-clavulanic acid, cefsulodin, and/or aztreonam, and/or sulfamethoxazol-trimethoprim, and/or fosfomycin. Finally, 8 Pseudomonas spp. isolates, related to the Pseudomonas putida and Pseudomonas fluorescens species, were isolated from the drinking water. Thus, Pseudomonas could be involved in the dissemination of antibiotic resistance via drinking water during critical periods. | 2014 | 24875257 |
| 7349 | 16 | 0.9958 | Bacterial and DNA contamination of a small freshwater waterway used for drinking water after a large precipitation event. Sewage contamination of freshwater occurs in the form of raw waste or as effluent from wastewater treatment plants (WWTP's). While raw waste (animal and human) and under-functioning WWTP's can introduce live enteric bacteria to freshwater systems, most WWTP's, even when operating correctly, do not remove bacterial genetic material from treated waste, resulting in the addition of bacterial DNA, including antibiotic resistance genes, into water columns and sediment of freshwater systems. In freshwater systems with both raw and treated waste inputs, then, there will be increased interaction between live sewage-associated bacteria (untreated sewage) and DNA contamination (from both untreated and treated wastewater effluent). To evaluate this understudied interaction between DNA and bacterial contamination in the freshwater environment, we conducted a three-month field-based study of sewage-associated bacteria and genetic material in water and sediment in a freshwater tributary of the Hudson River (NY, USA) that supplies drinking water and receives treated and untreated wastewater discharges from several municipalities. Using both DNA and culture-based bacterial analyses, we found that both treated and untreated sewage influences water and sediment bacterial communities in this tributary, and water-sediment exchanges of enteric bacteria and genetic material. Our results also indicated that the treated sewage effluent on this waterway serves as a concentrated source of intI1 (antibiotic resistance) genes, which appear to collect in the sediments below the outfall along with fecal indicator bacteria. Our work also captured the environmental impact of a large rain event that perturbed bacterial populations in sediment and water matrices, independently from the outflow. This study suggests that large precipitation events are an important cause of bacterial and DNA contamination for freshwater tributaries, with runoff from the surrounding environment being an important factor. | 2025 | 40096758 |
| 3156 | 17 | 0.9958 | Deciphering Resistome and Virulome Diversity in a Porcine Slaughterhouse and Pork Products Through Its Production Chain. We aimed to better understand resistome and virulome patterns on animal and process-area surfaces through a pig slaughterhouse to track possible contamination within the food production chain. Culture-dependent methods revealed high levels of microbial contamination, corresponding to mesophilic and pathogenic bacteria on both the animal and process-area surfaces mainly in the anesthesia (AA and AS) zone followed by "scorching and whip" (FA and FS) zone and also in the end products. To evaluate the potential risk of antibiotic resistance and virulence determinants, shotgun metagenomic DNA-sequencing of isolates from selected areas/products uncovered a high diversity and richness of antibiotic resistance genes (ARGs): 55-62 genes in the anesthesia area (AA and AS) and 35-40 in "animal-arrival zone" (MA and MS). The "scorching and whip" (FA and FS) area, however, exhibited lowered abundance of ARGs (1-6), indicating that the scalding and depilating process (an intermediate zone between "anesthesia" and "scorching and whip") significantly decreased bacterial load by 1-3 log(10) but also diminished the resistome. The high prevalence of antibiotic-inactivating enzyme genes in the "animal-arrival zone" (60-65%) and "anesthesia" area (56%) were mainly represented by those for aminoglycoside (46-51%) and lincosamide (14-19%) resistance, which did not reflect selective pressures by antibiotics most commonly used in pig therapy-tetracyclines and beta-lactams. Contrary to ARGs, greater number of virulence resistance genes were detected after evisceration in some products such as kidney, which reflected the poor hygienic practices. More than 19 general virulence features-mainly adherence, secretion system, chemotaxis and motility, invasion and motility were detected in some products. However, immune evasion determinants were detected in almost all samples analyzed from the beginning of the process, with highest amounts found from the anesthesia area. We conclude that there are two main sources of contamination in a pig slaughterhouse: the microorganisms carried on the animals' hide, and those from the evisceration step. As such, focussing control measures, e.g., enhanced disinfection procedures, on these contamination-source areas may reduce risks to food safety and consumer health, since the antibiotic and virulence determinants may spread to end products and the environment; further, ARG and virulence traits can exacerbate pathogen treatments. | 2018 | 30258416 |
| 3180 | 18 | 0.9958 | Residential urban stormwater runoff: A comprehensive profile of microbiome and antibiotic resistance. Non-point stormwater runoff is a major contamination source of receiving waterbodies. Heightened incidence of waterborne disease outbreaks related to recreational use and source water contamination is associated with extreme rainfall events. Such extreme events are predicted to increase in some regions due to climate change. Consequently, municipal separate storm sewer systems (MS4s) conveying pathogens to receiving waters are a growing public health concern. In addition, the spread of antibiotic resistance genes (ARGs) and antibiotic resistant bacteria in various environmental matrices, including urban runoff, is an emerging threat. The resistome and microbiota profile of MS4 discharges has yet to be fully characterized. To address this knowledge gap, we first analyzed the relationship between rainfall depth and intensity and E. coli densities (fecal indicator) in stormwater from four MS4 outflows in Columbus, Ohio, USA during the spring and summer of 2017. Microbial source tracking (MST) was conducted to examine major fecal contamination sources in the study sewersheds. A subset of samples was analyzed for microbial and resistome profiles using a metagenomic approach. The results showed a significant positive relationship between outflow E. coli density and rainfall intensity. MST results indicate prevalent fecal contamination from ruminant populations in the study sites (91% positive among the samples tested). Protobacteria and Actinobacteria were two dominant bacteria at a phylum level. A diverse array of ARGs and potentially pathogenic bacteria (e.g. Salmonella enterica Typhimurium), fungi (e.g. Scedosporium apiospermum), and protists (e.g. Acanthamoeba palestinensis) were found in urban stormwater outflows that discharge into adjacent streams. The most prevalent ARGs among samples were β-lactam resistance genes and the most predominant virulence genes within bacterial community were related with Staphylococcus aureus. A comprehensive contamination profile indicates a need for sustainable strategies to manage urban stormwater runoff amid increasingly intense rainfall events to protect public and environmental health. | 2020 | 32392682 |
| 5352 | 19 | 0.9958 | Microbiological characterization of aquatic microbiomes targeting taxonomical marker genes and antibiotic resistance genes of opportunistic bacteria. The dissemination of medically relevant antibiotic resistance genes (ARGs) (blaVIM-1, vanA, ampC, ermB, and mecA) and opportunistic bacteria (Enterococcus faecium/faecalis, Pseudomonas aeruginosa, Enterobacteriaceae, Staphylococcus aureus, and CNS) was determined in different anthropogenically influenced aquatic habitats in a selected region of Germany. Over a period of two years, four differently sized wastewater treatment plants (WWTPs) with and without clinical influence, three surface waters, four rain overflow basins, and three groundwater sites were analyzed by quantitative Polymerase Chain Reaction (qPCR). Results were calculated in cell equivalents per 100 ng of total DNA extracted from water samples and per 100 mL sample volume, which seems to underestimate the abundance of antibiotic resistance and opportunistic bacteria. High abundances of opportunistic bacteria and ARG were quantified in clinical wastewaters and influents of the adjacent WWTP. The removal capacities of WWTP were up to 99% for some, but not all investigated bacteria. The abundances of most ARG targets were found to be increased in the bacterial population after conventional wastewater treatment. As a consequence, downstream surface water and also some groundwater compartments displayed high abundances of all four ARGs. It became obvious that the dynamics of the ARG differed from the fate of the opportunistic bacteria. This underlines the necessity of an advanced microbial characterization of anthropogenically influenced environments. | 2015 | 25634736 |