Antibiotic resistome from the One-Health perspective: understanding and controlling antimicrobial resistance transmission

Antibiotic resistance genes of public health importance in livestock and humans in an informal urban community in Nepal

Efforts to mitigate the increasing emergence of antimicrobial resistance (AMR) will benefit from a One Health perspective, as over half of animal antimicrobials are also considered medically important in humans, and AMR can be maintained in the environment. This is especially pertinent to low- and middle-income countries and in community settings, where an estimated 80% of all antibiotics are used. This study features AMR genes found among humans, animals, and water at an urban informal settlement in Nepal with intensifying livestock production. We sampled humans, chickens, ducks, swine, and water clustered by household, as well as rodents and shrews near dwellings, concurrently in time in July 2017 in southeastern Kathmandu along the Manohara river. Real-time qualitative PCR was performed to screen for 88 genes. Our results characterize the animal-human-environmental interfaces related to the occurrence of specific resistance genes (bla_SHV-1 (SHV(238G240E) strain), QnrS, ermC, tetA, tetB, aacC2, aadA1) associated with antibiotics of global health importance that comprise several drug classes, including aminoglycosides, beta-lactams, tetracyclines, macrolides, and fluoroquinolones. By characterizing risk factors across AMR genes of public health importance, this research highlights potential transmission pathways for further investigation and provides prioritization of community-based prevention and intervention efforts for disrupting AMR transmission of critically important antibiotics used in both humans and animals in Nepal.

Long-term manure inputs induce a deep selection on agroecosystem soil antibiotic resistome

Although the enrichment of antibiotic resistance genes (ARGs) in diverse organic soils have been explored, understanding of the ecological processes governing the composition of ARGs in long-term organically fertilized soils still remains limited across typical agricultural regions. Thus, the distribution and assembly of ARG profile in three typical agricultural soils (black soil, fluvo-aquic soil, and red soil) under long-term contrasting fertilization regimes (chemical-only vs organic-only) were investigated using high-throughput qPCR (HT-qPCR). The application of organic manure significantly increased the abundance and number of ARGs across soils, as compared to those with chemical fertilizer. Organic manure application enriched the abundance of mobile genetic elements (MGEs), which were positively associated with ARGs. In addition, it is long-term organic fertilizer that enriched the number and abundance of opportunist and specialist ARGs in the fluvo-aquic and red soils, but not black soils. The number and abundance of most generalist ARGs did not change significantly among different fertilization or soil types. The assembly process of the ARG profiles tends to be more deterministic in organically fertilized soils than in chemically fertilized soils. These results suggest that long-term organic fertilizer application may contribute to the persistence and health risk of the soil antibiotic resistomes (especially specialist ARGs).

A one health approach versus Acanthamoeba castellanii, a potential host for Morganella morganii

Acanthamoeba castellanii, known as the “Trojan horse of the microbial world,” is known to host a variety of microorganisms including viruses, yeasts, protists, and bacteria. Acanthamoeba can act as a vector and may aid in the transmission of various bacterial pathogens to potential hosts and are found in a variety of places, thus impacting the health of humans, animals, and the environment. These are interconnected in a system known as “one health.” With the global threat of antibiotic resistance, bacteria may avoid harsh conditions, antibiotics, and disinfectants by sheltering within Acanthamoeba. In this study, Acanthamoeba castellanii interaction with Morganella morganii, a Gram-negative bacterium was studied. Escherichia coli K1 interaction with Acanthamoeba was carried out as a control. Association, invasion, and survival assays were accomplished. Morganella morganii was found to associate, invade, and survive within Acanthamoeba castellanii. Additionally, Escherichia coli K1 was also found to associate, invade, and survive within the Acanthamoeba at a higher number in comparison to Morganella morganii. For the first time, we have shown that Morganella morganii interact, invade, and survive within Acanthamoeba castellanii, suggesting that Acanthamoeba may be a potential vector in the transmission of Morganella morganii to susceptible hosts. Taking a one health approach to tackle and develop disinfectants to target Acanthamoeba is warranted, as the amoebae may be hosting various microbes such as multiple drug-resistant bacteria and even viruses such as the novel coronavirus.

Phage Products for Fighting Antimicrobial Resistance

Antimicrobial resistance (AMR) has become a global public health issue and antibiotic agents have lagged behind the rise in bacterial resistance. We are searching for a new method to combat AMR and phages are viruses that can effectively fight bacterial infections, which have renewed interest as antibiotic alternatives with their specificity. Large phage products have been produced in recent years to fight AMR. Using the “one health” approach, this review summarizes the phage products used in plant, food, animal, and human health. In addition, the advantages and disadvantages and future perspectives for the development of phage therapy as an antibiotic alternative to combat AMR are also discussed in this review.

The Urinary Resistome of Clinically Healthy Companion Dogs: Potential One Health Implications

An interdisciplinary approach to antimicrobial resistance (AMR) is essential to effectively address what is projected to soon become a public health disaster. Veterinary medicine accounts for a majority of antimicrobial use, and mainly in support of industrial food animal production (IFAP), which has significant exposure implications for human and nonhuman animals. Companion dogs live in close proximity to humans and share environmental exposures, including food sources. This study aimed to elucidate the AMR-gene presence in microorganisms recovered from urine from clinically healthy dogs to highlight public health considerations in the context of a species-spanning framework. Urine was collected through cystocentesis from 50 companion dogs in Southern California, and microbial DNA was analyzed using next-generation sequencing. Thirteen AMR genes in urine from 48% of the dogs {n=24} were detected. The most common AMR genes were aph(3')Ia, and ermB, which confer resistance to aminoglycosides and MLS (macrolides, lincosamides, streptogramins) antibiotics, respectively. Antibiotic-resistance profiles based on the AMR genes detected, and the intrinsic resistance profiles of bacterial species, were inferred in 24% of the samples {n=12} for 57 species, with most belonging to Streptococcus, Staphylococcus, and Corynebacterium genera. The presence of AMR genes that confer resistance to medically important antibiotics suggests that dogs may serve as reservoirs of clinically relevant resistomes, which is likely rooted in excessive IFAP antimicrobial use.

An Overview of Antimicrobial Stewardship Optimization: The Use of Antibiotics in Humans and Animals to Prevent Resistance

Antimicrobials are a type of agent widely used to prevent various microbial infections in humans and animals. Antimicrobial resistance is a major cause of clinical antimicrobial therapy failure, and it has become a major public health concern around the world. Increasing the development of multiple antimicrobials has become available for humans and animals with no appropriate guidance. As a result, inappropriate use of antimicrobials has significantly produced antimicrobial resistance. However, an increasing number of infections such as sepsis are untreatable due to this antimicrobial resistance. In either case, life-saving drugs are rendered ineffective in most cases. The actual causes of antimicrobial resistance are complex and versatile. A lack of adequate health services, unoptimized use of antimicrobials in humans and animals, poor water and sanitation systems, wide gaps in access and research and development in healthcare technologies, and environmental pollution have vital impacts on antimicrobial resistance. This current review will highlight the natural history and basics of the development of antimicrobials, the relationship between antimicrobial use in humans and antimicrobial use in animals, the simplistic pathways, and mechanisms of antimicrobial resistance, and how to control the spread of this resistance.

Comprehensive pan-genomic, resistome and virulome analysis of clinical OXA-48 producing carbapenem-resistant Serratia marcescens strains

BACKGROUND

Carbapenem-resistant Enterobacteriaceae (CRE) have been thoroughly studied as the pathogens associated with hospital acquired infections. However, data on Serratia marcescens are not enough. S. marcescens is now becoming a propensity for its highly antimicrobial-resistant clinical infections.

METHODS

Four carbapenem-resistant S. marcescens (CR-SM) isolates were obtained from hospitalized patients through routine microbiological experiments. We assembled the isolates genomes using whole genome sequencing (WGS) and compared their resistome and virulome patterns.

RESULTS

The average length and CG content of chromosomes was 5.33 Mbp and 59.8%, respectively. The number of coding sequences (CDSs) ranged from 4,959 to 4,989. All strains had one single putative conjugative plasmid with IncL incompatibility (Inc) group. The strains harbored bla_CTX-M-15, bla_TEM-1 and bla_SHV-134. All plamsids were positive for bla_OXA-48. No bla_NDM-1, bla_KPC, bla_VIM and bla_IMP were identified. The bla_SRT-2 and aac(6')-Ic genes were chromosomally-encoded. Class 1 integron was detected in strains P8, P11 and P14. The Escher_RCS47 and Salmon_SJ46 prophages played major role in plasmid-mediated carraige of extended spectrum β-lactamases (ESBLs). The CR-SM strains were equipt with typical virulence factors of oppotunistic pathogens including biofilm formation, adhesins, secretory systems and siderophores. The strains did not have ability to produce prodigiosin but were positive for chitinase and EstA.

CONCLUSION

The presence of conjugative plasmids harboring major β-lactamases within prophage and class 1 integron structures highlights the role of different mobile genetic elements (MGEs) in distribution of AMR factors and more specifically carbapenemases. More molecular studies are required to determine the status of carbapenem resistance in clinical starins. However, appropriate strategies to control the global dissemination of CR-SM are urgent.

Effect of inlet-outlet configurations on the cross-transmission of airborne bacteria between animal production buildings

Cross-transmission of airborne pathogens between buildings facilitates the spread of both human and animal diseases. Rational spatial arrangement of buildings and air inlet-outlet design are well-established preventive measures, but the effectiveness of current configurations for mitigating pathogens cross-transmission is still under assessment. An intensive field study in a laying hen farm was conducted to elucidate the spatial distribution of airborne bacteria (AB) and the source of AB at the inlets under different wind regimes. We found higher concentrations of AB at the interspace and sidewall inlets of buildings with sidewall exhaust systems than at those with endwall exhaust systems. We observed significant differences in bacterial diversity and richness at the interspace and sidewall inlets between buildings with side exhaust systems and those with endwall exhaust systems. We further found that the AB emitted from buildings could translocate to the sidewall inlets of adjacent building to a greater extent between buildings with sidewall exhaust systems than between those with endwall exhaust systems. Our findings revealed that sidewall exhaust systems aggravate cross-transmission of AB between buildings, suggesting that endwall exhaust systems or other compensatory preventive measures combined with sidewall exhaust systems could be a better choice to suppress airborne cross-transmission.

Pneumonia surveillance with culture-independent metatranscriptomics in HIV-positive adults in Uganda: a cross-sectional study

BACKGROUND

Pneumonia is a leading cause of death worldwide and is a major health-care challenge in people living with HIV. Despite this, the causes of pneumonia in this population remain poorly understood. We aimed to assess the feasibility of metatranscriptomics for epidemiological surveillance of pneumonia in patients with HIV in Uganda.

METHODS

We performed a retrospective observational study in patients with HIV who were admitted to Mulago Hospital, Kampala, Uganda between Oct 1, 2009, and Dec 31, 2011. Inclusion criteria were age 18 years or older, HIV-positivity, and clinically diagnosed pneumonia. Exclusion criteria were contraindication to bronchoscopy or an existing diagnosis of tuberculosis. Bronchoalveolar lavage fluid was collected within 72 h of admission and a combination of RNA sequencing and Mycobacterium tuberculosis culture plus PCR were performed. The primary outcome was detection of an established or possible respiratory pathogen in the total study population.

FINDINGS

We consecutively enrolled 217 patients during the study period. A potential microbial cause for pneumonia was identified in 211 (97%) patients. At least one microorganism of established respiratory pathogenicity was identified in 113 (52%) patients, and a microbe of possible pathogenicity was identified in an additional 98 (45%). M tuberculosis was the most commonly identified established pathogen (35 [16%] patients; in whom bacterial or viral co-infections were identified in 13 [37%]). Streptococcus mitis, although not previously reported as a cause of pneumonia in patients with HIV, was the most commonly identified bacterial organism (37 [17%] patients). Haemophilus influenzae was the most commonly identified established bacterial pathogen (20 [9%] patients). Pneumocystis jirovecii was only identified in patients with a CD4 count of less than 200 cells per mL.

INTERPRETATION

We show the feasibility of using metatranscriptomics for epidemiologic surveillance of pneumonia by describing the spectrum of respiratory pathogens in adults with HIV in Uganda. Applying these methods to a contemporary cohort could enable broad assessment of changes in pneumonia aetiology following the emergence of SARS-CoV-2.

FUNDING

US National Institutes of Health, Chan Zuckerberg Biohub.

Systematic Review and Meta-Analysis of Integrated Studies on Salmonella and Campylobacter Prevalence, Serovar, and Phenotyping and Genetic of Antimicrobial Resistance in the Middle East—A One Health Perspective

Background:Campylobacter and Salmonella are the leading causes of foodborne diseases worldwide. Recently, antimicrobial resistance (AMR) has become one of the most critical challenges for public health and food safety. To investigate and detect infections commonly transmitted from animals, food, and the environment to humans, a surveillance–response system integrating human and animal health, the environment, and food production components (iSRS), called a One Health approach, would be optimal. Objective: We aimed to identify existing integrated One Health studies on foodborne illnesses in the Middle East and to determine the prevalence, serovars, and antimicrobial resistance phenotypes and genotypes of Salmonella and Campylobacter strains among humans and food-producing animals. Methods: The databases Web of Science, Scopus, and PubMed were searched for literature published from January 2010 until September 2021. Studies meeting inclusion criteria were included and assessed for risk of bias. To assess the temporal and spatial relationship between resistant strains from humans and animals, a statistical random-effects model meta-analysis was performed. Results: 41 out of 1610 studies that investigated Campylobacter and non-typhoid Salmonella (NTS) in the Middle East were included. The NTS prevalence rates among human and food-producing animals were 9% and 13%, respectively. The Campylobacter prevalence rates were 22% in humans and 30% in food-producing animals. The most-reported NTS serovars were Salmonella Enteritidis and Salmonella Typhimurium, while Campylobacter jejuni and Campylobacter coli were the most prevalent species of Campylobacter. NTS isolates were highly resistant to erythromycin, amoxicillin, tetracycline, and ampicillin. C. jejuni isolates showed high resistance against amoxicillin, trimethoprim–sulfamethoxazole, nalidixic acid, azithromycin, chloramphenicol, ampicillin, tetracycline, and ciprofloxacin. The most prevalent Antimicrobial Resistance Genes (ARGs) in isolates from humans included tetO (85%), Class 1 Integrons (81%), blaOXA-61 (53%), and cmeB (51%), whereas in food-producing animals, the genes were tetO (77%), Class 1 integrons (69%), blaOXA-61 (35%), and cmeB (35%). The One Health approach was not rigorously applied in the Middle East countries. Furthermore, there was an uneven distribution in the reported data between the countries. Conclusion: More studies using a simultaneous approach targeting human, animal health, the environment, and food production components along with a solid epidemiological study design are needed to better understand the drivers for the emergence and spread of foodborne pathogens and AMR in the Middle East.

Emerging Concern with Imminent Therapeutic Strategies for Treating Resistance in Biofilm

Biofilm production by bacteria is presumed to be a survival strategy in natural environments. The production of biofilms is known to be influenced by a number of factors. This paper has precisely elaborated on the different factors that directly influence the formation of biofilm. Biofilm has serious consequences for human health, and a variety of infections linked to biofilm have emerged, rapidly increasing the statistics of antimicrobial resistance, which is a global threat. Additionally, to combat resistance in biofilm, various approaches have been developed. Surface modifications, physical removal, and the use of nanoparticles are the recent advances that have enabled drug discovery for treating various biofilm-associated infections. Progress in nanoparticle production has led to the development of a variety of biofilm-fighting strategies. We focus on the present and future therapeutic options that target the critical structural and functional characteristics of microbial biofilms, as well as drug tolerance mechanisms, such as the extracellular matrix, in this review.

The plant microbiota signature of the Anthropocene as a challenge for microbiome research

BACKGROUND

One promise of the recently presented microbiome definition suggested that, in combination with unifying concepts and standards, microbiome research could be important for solving new challenges associated with anthropogenic-driven changes in various microbiota. With this commentary we want to further elaborate this suggestion, because we noticed specific signatures in microbiota affected by the Anthropocene.

RESULTS

Here, we discuss this based on a review of available literature and our own research targeting exemplarily the plant microbiome. It is not only crucial for plants themselves but also linked to planetary health. We suggest that different human activities are commonly linked to a shift of diversity and evenness of the plant microbiota, which is also characterized by a decrease of host specificity, and an increase of r-strategic microbes, pathogens, and hypermutators. The resistome, anchored in the microbiome, follows this shift by an increase of specific antimicrobial resistance (AMR) mechanisms as well as an increase of plasmid-associated resistance genes. This typical microbiome signature of the Anthropocene is often associated with dysbiosis and loss of resilience, and leads to frequent pathogen outbreaks. Although several of these observations are already confirmed by meta-studies, this issue requires more attention in upcoming microbiome studies.

CONCLUSIONS

Our commentary aims to inspire holistic studies for the development of solutions to restore and save microbial diversity for ecosystem functioning as well as the closely connected planetary health. Video abstract.

Antimicrobial Resistance in Rivers: A Review of the Genes Detected and New Challenges

River ecosystems are very important parts of the water cycle and an excellent habitat, food, and drinking water source for many organisms, including humans. Antibiotics are emerging contaminants which can enter rivers from various sources. Several antibiotics and their related antibiotic resistance genes (ARGs) have been detected in these ecosystems by various research programs and could constitute a substantial problem. The presence of antibiotics and other resistance cofactors can boost the development of ARGs in the chromosomes or mobile genetic elements of natural bacteria in rivers. The ARGs in environmental bacteria can also be transferred to clinically important pathogens. However, antibiotics and their resistance genes are both not currently monitored by national or international authorities responsible for controlling the quality of water bodies. For example, they are not included in the contaminant list in the European Water Framework Directive or in the US list of Water-Quality Benchmarks for Contaminants. Although ARGs are naturally present in the environment, very few studies have focused on non-impacted rivers to assess the background ARG levels in rivers, which could provide some useful indications for future environmental regulation and legislation. The present study reviews the antibiotics and associated ARGs most commonly measured and detected in rivers, including the primary analysis tools used for their assessment. In addition, other factors that could enhance antibiotic resistance, such as the effects of chemical mixtures, the effects of climate change, and the potential effects of the coronavirus disease 2019 pandemic, are discussed. Environ Toxicol Chem 2022;41:687-714. © 2022 SETAC.

Altered Ecology of the Respiratory Tract Microbiome and Nosocomial Pneumonia

Nosocomial pneumonia is one of the most frequent infections in critical patients. It is primarily associated with mechanical ventilation leading to severe illness, high mortality, and prolonged hospitalization. The risk of mortality has increased over time due to the rise in multidrug-resistant (MDR) bacterial infections, which represent a global public health threat. Respiratory tract microbiome (RTM) research is growing, and recent studies suggest that a healthy RTM positively stimulates the immune system and, like the gut microbiome, can protect against pathogen infection through colonization resistance (CR). Physiological conditions of critical patients and interventions as antibiotics administration and mechanical ventilation dramatically alter the RTM, leading to dysbiosis. The dysbiosis of the RTM of ICU patients favors the colonization by opportunistic and resistant pathogens that can be part of the microbiota or acquired from the hospital environments (biotic or built ones). Despite recent evidence demonstrating the significance of RTM in nosocomial infections, most of the host-RTM interactions remain unknown. In this context, we present our perspective regarding research in RTM altered ecology in the clinical environment, particularly as a risk for acquisition of nosocomial pneumonia. We also reflect on the gaps in the field and suggest future research directions. Moreover, expected microbiome-based interventions together with the tools to study the RTM highlighting the "omics" approaches are discussed.

Measuring the Link Between Vaccines and Antimicrobial Resistance in Low Resource Settings – Limitations and Opportunities in Direct and Indirect Assessments and Implications for Impact Studies

The importance of vaccines in combatting antimicrobial resistance (AMR) is commonly accepted. Although scientific reasoning supports the putative connection between vaccines and reduction of AMR, reliably measuring the magnitude and effect of vaccines on antimicrobial resistance is inherently challenging, especially in low resource settings. We review the intrinsic challenges in estimating the effect of vaccines on AMR and discuss the limitations and opportunities in current methods from the host, pathogen, and environment perspectives. We highlight advantages and pitfalls in different epidemiological study designs with a specific focus on impact studies in low resource settings and suggest how these perspectives could be considered in future research.

Of Cockroaches and Symbionts: Recent Advances in the Characterization of the Relationship between Blattella germanica and Its Dual Symbiotic System

Mutualistic stable symbioses are widespread in all groups of eukaryotes, especially in insects, where symbionts have played an essential role in their evolution. Many insects live in obligate relationship with different ecto- and endosymbiotic bacteria, which are needed to maintain their hosts’ fitness in their natural environment, to the point of even relying on them for survival. The case of cockroaches (Blattodea) is paradigmatic, as both symbiotic systems coexist in the same organism in two separated compartments: an intracellular endosymbiont (Blattabacterium) inside bacteriocytes located in the fat body, and a rich and complex microbiota in the hindgut. The German cockroach Blattella germanica is a good model for the study of symbiotic interactions, as it can be maintained in the laboratory in controlled populations, allowing the perturbations of the two symbiotic systems in order to study the communication and integration of the tripartite organization of the host–endosymbiont–microbiota, and to evaluate the role of symbiotic antimicrobial peptides (AMPs) in host control over their symbionts. The importance of cockroaches as reservoirs and transmission vectors of antibiotic resistance sequences, and their putative interest to search for AMPs to deal with the problem, is also discussed.

Should All Fractions of the Boar Ejaculate Be Prepared for Insemination Rather Than Using the Sperm Rich Only?

Simple Summary

The swine industry is constantly looking for efficiency improvement, especially focusing on the artificial insemination (AI) process. One of the trends in AI centers is to maximize the number of doses obtained from one ejaculate. Seminal doses are usually prepared with the sperm-rich fraction or the whole ejaculate, but further studies are needed to understand how to prepare them properly. Thus, this study aims to analyze how accumulative ejaculate fractions may influence sperm storage, AI performance, and offspring. The results indicate that the presence of all ejaculate fractions within seminal doses does not affect either sperm quality or AI performance and offspring health. Therefore, this study highlights the possibility to use the bulk ejaculate for seminal dose preparation, leading to successful AI. Additionally, it results in a more time-efficient preparation of a greater number of seminal doses providing an economic advantage.

Abstract

Boar ejaculate is released in several well-characterized fractions, differing in terms of sperm concentration, seminal plasma volume, and composition. However, the inclusion of the last part of the ejaculate for artificial insemination (AI) purposes is still under debate due to its controversial effects. Thus, there is a need to study the potential synergistic impact of the different ejaculate fractions. We aimed to evaluate the effect of accumulative ejaculate fractions on sperm conservation, AI performance, and offspring health. Ejaculates (n = 51) were collected and distributed as follows: F1: sperm-rich fraction; F2: sperm-rich + intermediate fractions; F3: sperm-rich + intermediate + poor fractions. Each group was diluted in a commercial extender, packaged in seminal doses (2000 × 10⁶ sperm/60 mL), and stored at ~16 °C. On day 3 of conservation, sperm were analyzed and used for AI (n = 174). High sperm quality was observed after storage without a significant difference between the groups (p > 0.05). Moreover, no differences were obtained for AI performance (pregnancy and farrowing rates, and litter size; p > 0.05) and offspring health (growth and blood analysis; p > 0.05). Conclusively, the presence of all ejaculate fractions within the seminal doses does not impair the reproductive performance, reporting important economic savings according to the economic model included here.

A Risk-Based Approach for Managing Aquaculture Used Oxytetracycline-Induced TetR in Surface Water Across Taiwan Regions

Oxytetracycline (OTC), one of the most important antibiotics in aquaculture industry, has been linked to emergence of antibiotic resistant genes in the aquatic environment. Given rapid growth of the aquaculture industry and unregulated use of antibiotics, it is necessary to implement measures to mitigate the impact of antibiotic resistance risk on environmental and human health. However, there is a lack of quantitative models to properly assess risk of antibiotic resistance associated with environmentally relevant antibiotic residues. To address this issue, here we developed a computational framework to assess antibiotic resistance risk posed by low-concentration OTC in aquaculture ponds and rivers across Taiwan regions. To this end, estimated amount of aquaculture used OTC as a crucial input parameter was incorporated into a multimedia fugacity model to predict environmental concentrations of OTC in surface water/sediment. A pharmacodynamic-based dose–response model was used to characterize the OTC concentration–antibiotic resistance relationships. The risk of antibiotic resistance selection in an aquatic environment could be assessed based on a probabilistic risk model. We also established a control measure model to manage the risks of substantial OTC-induced antibiotic resistance impacts. We found that OTC residues were likely to pose a high risk of tetracycline resistance (tetR) genes selection in aquaculture ponds among all the study basins, whereas risk of tetR genes selection in rivers experienced a variably changing fashion. We also showed that it was extremely difficult to moderate the tetR genes selection rates to less than 10% increase in aquaculture ponds situated at northeastern river basins in that the minimum reductions on OTC emission rates during spring, summer, and autumn were greater than 90%. On the other hand, water concentrations of OTC during spring and summer in southwestern rivers should be prioritized to be severely limited by reducing 67 and 25% of OTC emission rate, respectively. Overall, incorporating a computational fugacity model into a risk assessment framework can identify relative higher risk regions to provide the risk-based control strategies for public health decision-making and development of robust quantitative methods to zero-in on environment with high risk of tetR genes selection in relation to aquaculture-used pharmaceutical residues.

Catalytic Use toward the Redox Reaction of Toxic Industrial Wastes in Innocuous Aqueous Medium and Antibacterial Activity of Novel Cu x Ag x Zn1-2x O Nanocomposites

In this work, we report the redox properties in organic catalytic transformation and antibacterial activity of novel Cu x Ag x Zn1-2x O nanocomposites. Cu- and Ag-doped ZnO [Cu x Ag x Zn1-2x O (x = 0.1)] (CAZ), Cu-doped ZnO [Cu x Zn1-x O (x = 0.1)] (CZ), and Ag-doped ZnO [Ag x Zn1-x O (x = 0.1)] (AZ) were prepared via a chemical co-precipitation method. The synthesized nanocomposites were characterized using different spectroscopic techniques. The catalytic activity of CAZ, CZ, and AZ was examined for the reduction of 4-nitrophenol (4-NP) and 4-nitroaniline (4-NA) in the presence of NaBH4 in an aqueous medium. The photocatalytic oxidation efficiency of these catalysts was also observed against naphthol orange (NO) under ultraviolet light. It was found that the catalytic reduction and oxidation efficiency of CAZ is higher than that of CZ and AZ in 4-NP/4-NA and NO in a water solvent, respectively. The antibacterial property of CAZ was also studied against Gram-positive and Gram-negative bacteria by agar well diffusion and the minimum inhibitory concentration methods. It was found that CAZ shows better antimicrobial activity compared to its parental Cu(NO3)2·3H2O, AgNO3, and ZnO. Therefore, the incorporation of Cu and Ag into ZnO increases its catalytic and antimicrobial activity remarkably. Fourier-transform infrared and X-ray diffraction (XRD) studies of CAZ indicate the incorporation of Cu and Ag into the lattice of ZnO. The phase structure of CAZ was wurtzite hexagonal, and the average crystallite size was 93 ± 1 nm measured from XRD. The average grain size and particle size of CAZ were found to be 200 and 100 ± 5 nm originating from SEM and transmission electron microscopy studies, respectively. The optical energy band gap of CAZ is 3.15 eV, which supports the excellent photocatalyst under UV light. CAZ also exhibits good agreement for photoluminescence properties with a high intensity peak at 571 nm, indicating surface oxygen vacancies and defects which might be responsible for higher photocatalytic activity compared to others. The nanocomposite shows excellent reusability without any significant loss of activity.

Antimicrobial-Resistant Escherichia coli Strains and Their Plasmids in People, Poultry, and Chicken Meat in Laos

Antimicrobial resistant (AMR) Enterobacterales are widely distributed among the healthy population of the Indochinese peninsula, including Laos. However, the local reservoir of these pathogens are currently not known and possible sources such as agricultural settings and food have rarely been analyzed. In this work, we investigated the extended-spectrum cephalosporin- (ESC-) and colistin-resistant Escherichia coli strains (CST-R-Ec) isolated from the gut of local people, feces of poultry, and from chicken meat (60 samples each group) in Laos. Whole-genome sequencing (WGS) analysis based on both short- and long-read sequencing approaches were implemented. The following prevalence of ESC-R-Ec and CST-R-Ec were recorded, respectively: local people (70 and 15%), poultry (20 and 23.3%), and chicken meat (21.7 and 13.3%). Core-genome analysis, coupled with sequence type (ST)/core-genome ST (cgST) definitions, indicated that no common AMR-Ec clones were spreading among the different settings. ESC-R-Ec mostly possessed bla_CTX–M–15 and bla_CTX–M–55 associated to ISEcp1 or IS26. The majority of CST-R-Ec carried mcr-1 on IncX4, IncI2, IncP1, and IncHI1 plasmids similar or identical to those described worldwide; strains with chromosomal mcr-1 or possessing plasmid-mediated mcr-3 were also found. These results indicate a high prevalence of AMR-Ec in the local population, poultry, and chicken meat. While we did not observe the same clones among the three settings, most of the bla_CTX–Ms and mcr-1/-3 were associated with mobile-genetic elements, indicating that horizontal gene transfer may play an important role in the dissemination of AMR-Ec in Laos. More studies should be planned to better understand the extent and dynamics of this phenomenon.

Fighting Antibiotic Resistance in Hospital-Acquired Infections: Current State and Emerging Technologies in Disease Prevention, Diagnostics and Therapy

Rising antibiotic resistance is a global threat that is projected to cause more deaths than all cancers combined by 2050. In this review, we set to summarize the current state of antibiotic resistance, and to give an overview of the emerging technologies aimed to escape the pre-antibiotic era recurrence. We conducted a comprehensive literature survey of >150 original research and review articles indexed in the Web of Science using "antimicrobial resistance," "diagnostics," "therapeutics," "disinfection," "nosocomial infections," "ESKAPE pathogens" as key words. We discuss the impact of nosocomial infections on the spread of multi-drug resistant bacteria, give an overview over existing and developing strategies for faster diagnostics of infectious diseases, review current and novel approaches in therapy of infectious diseases, and finally discuss strategies for hospital disinfection to prevent MDR bacteria spread.

First 1000 Days of Life: Consequences of Antibiotics on Gut Microbiota

The developmental origin of health and disease highlights the importance of the period of the first 1000 days (from conception to 2 years) of life. In particular, the process of gut microbiota establishment occurs within this time window. Therefore, determinants interfering with neonatal gut establishment may disrupt its physiological functions and potentially lead to negative health outcomes. Antibiotics are among perinatal determinants that can directly or indirectly affect the pattern of gut bacterial colonization, with a long-lasting impact on intestinal ecosystem functions. In this review, we will examine the impact of antibiotics on the intestinal microbiota during the perinatal period and first years of life, a key interval for development of an individual’s health capital. Further, we will discuss the role of antibiotics during short- and long-term dysbiosis and their associated health consequences.

Influence of Human Eating Habits on Antimicrobial Resistance Phenomenon: Aspects of Clinical Resistome of Gut Microbiota in Omnivores, Ovolactovegetarians, and Strict Vegetarians

The use of xenobiotics in food production and how food intake is carried out in different cultures, along with different eating habits (omnivorism (ON), ovolactovegetarianism (VT), and strict vegetarianism (VG)) seem to have implications for antimicrobial resistance, especially in the human gut microbiota. Thus, the aim of this study was to evaluate aspects of the clinical resistome of the human gut microbiota among healthy individuals with different eating habits. Volunteers were divided into 3 groups: n = 19 omnivores (ON), n = 20 ovolactovegetarians (VT), and n = 19 strict vegetarians (VG), and nutritional and anthropometric parameters were measured. Metagenomic DNA from fecal samples was used as a template for PCR screening of 37 antimicrobial resistance genes (ARG) representative of commonly used agents in human medicine. The correlation between eating habits and ARG was evaluated. There were no significant differences in mean caloric intake. Mean protein intake was significantly higher in ON, and fiber and carbohydrate consumption was higher in VG. From the screened ARG, 22 were detected. No clear relationship between diets and the occurrence of ARG was observed. Resistance genes against tetracyclines, β-lactams, and the MLS group (macrolides, lincosamides, and streptogramins) were the most frequent, followed by resistance genes against sulfonamides and aminoglycosides. Vegetables and minimally processed foods seem to be the main source of ARG for the human gut microbiota. Although eating habits vary among individuals, the open environment and the widespread ARG from different human activities draw attention to the complexity of the antimicrobial resistance phenomenon which should be addressed by a One Health approach.