Antibiotic resistance-the need for global solutions

The photo-based treatment technology simultaneously removes resistant bacteria and resistant genes from wastewater

Because of the recent widespread usage of antibiotics, the acquisition and dissemination of antibiotic-resistance genes (ARGs) were prevalent in the majority of habitats. Generally, the biological wastewater treatment processes used in wastewater treatment plants have a limited efficiencies of antibiotics resistant bacteria (ARB) disinfection and ARGs degradation and even promote the proliferation of ARGs. Problematically, ARB and ARGs in effluent pose potential risks if they are not further treated. Photocatalytic oxidation is considered a promising disinfection technology, where the photocatalytic process generates many free radicals that enhance the interaction between light and deoxyribonucleic acid (DNA) for ARB elimination and subsequent degradation of ARGs. This review aims to illustrate the progress of photocatalytic oxidation technology for removing antibiotics resistant (AR) from wastewater in recent years. We discuss the sources and transfer of ARGs in wastewater. The overall removal efficiencies of ultraviolet radiation (UV)/chlorination, UV/ozone, UV/H2O2, and UV/sulfate-radical based system for ARB and ARGs, as well as the experimental parameters and removal mechanisms, are systematically discussed. The contribution of photocatalytic materials based on TiO2 and g-C3N4 to the inactivation of ARB and degradation of ARGs is highlighted, producing many free radicals to attack ARB and ARGs while effectively limiting the horizontal gene transfer (HGT) in wastewater. Finally, based on the reviewed studies, future research directions are proposed to realize specific photocatalytic oxidation technology applications and overcome current challenges.

Intrinsic antimicrobial resistance: Molecular biomaterials to combat microbial biofilms and bacterial persisters

The escalating rise in antimicrobial resistance (AMR) coupled with a declining arsenal of new antibiotics is imposing serious threats to global public health. A pervasive aspect of many acquired AMR infections is that the pathogenic microorganisms exist as biofilms, which are equipped with superior survival strategies. In addition, persistent and recalcitrant infections are seeded with bacterial persister cells at infection sites. Together, conventional antibiotic therapeutics often fail in the complete treatment of infections associated with bacterial persisters and biofilms. Novel therapeutics have been attempted to tackle AMR, biofilms, and persister-associated complex infections. This review focuses on the progress in designing molecular biomaterials and therapeutics to address acquired and intrinsic AMR, and the fundamental microbiology behind biofilms and persisters. Starting with a brief introduction of AMR basics and approaches to tackling acquired AMR, the emphasis is placed on various biomaterial approaches to combating intrinsic AMR, including (1) semi-synthetic antibiotics; (2) macromolecular or polymeric biomaterials mimicking antimicrobial peptides; (3) adjuvant effects in synergy; (4) nano-therapeutics; (5) nitric oxide-releasing antimicrobials; (6) antimicrobial hydrogels; (7) antimicrobial coatings. Particularly, the structure-activity relationship is elucidated in each category of these biomaterials. Finally, illuminating perspectives are provided for the future design of molecular biomaterials to bypass AMR and cure chronic multi-drug resistant (MDR) infections.

Comprehensive analysis of distribution characteristics and horizontal gene transfer elements of blaNDM-1-carrying bacteria

The worldwide dissemination of New Delhi metallo-β-lactamase-1 (NDM-1), which mediates resistance to almost all clinical β-lactam antibiotics, is a major public health problem. The global distribution, species, sources, and potential transfer risk of blaNDM-1-carrying bacteria are unclear. Results of a comprehensive analysis of literature in 2010-2022 showed that a total of 6002 blaNDM-1 carrying bacteria were widely distributed around 62 countries with a high trend in the coastal areas. Opportunistic pathogens or pathogens like Klebsiella sp., Escherichia sp., Acinetobacter sp. and Pseudomonas sp. were the four main species indicating the potential microbial risk. Source analysis showed that 86.45 % of target bacteria were isolated from the source of hospital (e.g., Hospital patients and wastewater) and little from surface water (5.07 %) and farms (3.98 %). A plasmid-encoded blaNDM-1Acinetobacter sp. with the resistance mechanisms of antibiotic efflux pump, antibiotic target change and antibiotic degradation was isolated from the wastewater of a typical tertiary hospital. Insertion sequences (IS3 and IS30) located in the adjacent 5 kbp of blaNDM-1-bleMBL gene cluster indicating the transposon-mediated horizontal gene transfer risk. These results showed that the worldwide spread of blaNDM-1-carrying bacteria and its potential horizontal gene transfer risk deserve good control.

Synthesis and antibacterial medicinal evaluation of carbothioamido hydrazonyl thiazolylquinolone with multitargeting antimicrobial potential to combat increasingly global resistance

The global microbial resistance is a serious threat to human health, and multitargeting compounds are considered to be promising to combat microbial resistance. In this work, a series of new thiazolylquinolones with multitargeting antimicrobial potential were developed through multi-step reactions using triethoxymethane and substituted anilines as start materials. Their structures were confirmed by 1H NMR, 13C NMR and HRMS spectra. Antimicrobial evaluation revealed that some of the target compounds could effectively inhibit microbial growth. Especially, carbothioamido hydrazonyl aminothiazolyl quinolone 8a showed strong inhibitory activity toward drug-resistant Staphylococcus aureus with MIC value of 0.0047 mM, which was 5-fold more active than that of norfloxacin. The highly active compound 8a exhibited negligible hemolysis, no significant toxicity in vitro and in vivo, low drug resistance, as well as rapidly bactericidal effects, which suggested its favorable druggability. Furthermore, compound 8a was able to effectively disrupt the integrity of the bacterial membrane, intercalate into DNA and inhibit the activity of topoisomerase IV, suggesting multitargeting mechanism of action. Compound 8a could form hydrogen bonds and hydrophobic interactions with DNA-topoisomerase IV complex, indicating the insertion of aminothiazolyl moiety was beneficial to improve antibacterial efficiency. These findings indicated that the active carbothioamido hydrazonyl aminothiazolyl quinolone 8a as a chemical therapeutic candidate demonstrated immense potential to tackle drug-resistant bacterial infections.

An elephant in the room? Explaining agenda-setting in antimicrobial resistance policies in 30 European countries

Antimicrobial resistances (AMR) present a particularly challenging cross-sectoral policy problem, affecting human and animal health as well as the environment. Compared to the actual problem pressure, the public awareness for AMR is comparatively low and the issue has not been high on the political agenda in most. Given the rising problem pressure, we aim to find out as to what degree and under which conditions political parties bring AMR on the political agenda. By means of multilevel logit regressions based on 173 electoral manifestos in 30 European countries from 2015 to 2020, we explore the conditions that explain whether AMR are taken up in manifestos. The empirical findings indicate firstly that AMR are only addressed by political parties in Northern and Western Europe, in no case in Eastern, and only in one case in Southern Europe, though resistant bacteria are more widely spread in the latter. Secondly, Green parties are those who are most likely to address the AMR challenge. Thirdly, vote share is positively associated with AMR agenda-setting, while EU membership is insignificant and the national average on antibiotics consumption is negatively related to AMR agenda-setting. Finally, AMR are surprisingly mainly perceived as a problem of the agricultural policy subsystem despite its cross-sectoral policy character. The study makes theoretical and empirical contributions: regarding theory, the article shows that typical variables that are used for agenda-setting are less explanatory for complex intersectoral policies. This is also accompanied by the empirical contribution: since problem awareness and complexity of policy problems are correlated, AMR are reduced to an agricultural issue and as such, it is taken over by political parties that have expertise on agricultural-environmental topics.

Cost-Effectiveness of Test-and-Treat Strategies to Reduce the Antibiotic Prescription Rate for Acute Febrile Illness in Primary Healthcare Clinics in Africa

BACKGROUND

Inappropriate antibiotic use increases selective pressure, contributing to antimicrobial resistance. Point-of-care rapid diagnostic tests (RDTs) would be instrumental to better target antibiotic prescriptions, but widespread implementation of diagnostics for improved management of febrile illnesses is limited.

OBJECTIVE

Our study aims to contribute to evidence-based guidance to inform policymakers on investment decisions regarding interventions that foster more appropriate antibiotic prescriptions, as well as to address the evidence gap on the potential clinical and economic impact of RDTs on antibiotic prescription.

METHODS

A country-based cost-effectiveness model was developed for Burkina Faso, Ghana and Uganda. The decision tree model simulated seven test strategies for patients with febrile illness to assess the effect of different RDT combinations on antibiotic prescription rate (APR), costs and clinical outcomes. The incremental cost-effectiveness ratio (ICER) was expressed as the incremental cost per percentage point (ppt) reduction in APR.

RESULTS

For Burkina Faso and Uganda, testing all patients with a malaria RDT was dominant compared to standard-of-care (SoC) (which included malaria testing). Expanding the test panel with a C-reactive protein (CRP) test resulted in an ICER of $ 0.03 and $ 0.08 per ppt reduction in APR for Burkina Faso and Uganda, respectively. For Ghana, the pairwise comparison with SoC-including malaria and complete blood count testing-indicates that both testing with malaria RDT only and malaria RDT + CRP are dominant.

CONCLUSION

The use of RDTs for patients with febrile illness could effectively reduce APR at minimal additional costs, provided diagnostic algorithms are adhered to. Complementing SoC with CRP testing may increase clinicians' confidence in prescribing decisions and is a favourable strategy.

Recent advancements on antibiotic bioremediation in wastewaters with a focus on algae: an overview

Antibiotic contamination from hospitals, animal husbandry, and municipal wastewater is graver than imagined, and it possess serious risks to the health of humans and animals, with the emergence of multidrug resistant bacteria; those affect the growth of higher plants too. Conventional wastewater treatment methods adopted today are inadequate for removing antibiotics from wastewater. Intuitively, the remediation process using mixed algae should be effective enough, for which algae-based remediation technologies have emerged as sustainable remedial methods. This review summarized the detection of antibiotics in field water in most countries; a comprehensive overview of algae-based technologies, algal adsorption, accumulation, biodegradation, photodegradation, hydrolysis, and the use of algae-bacteria consortia for the remediation of antibiotics in wastewaters in done. Green algae namely, Chlamydomonas sp., Chlorella sp., C. vulgaris, Spyrogira sp. Scenedesmus quadricauda, S. obliquus, S. dimorphus, Haematoccus pluvialis, and Nannochlopsis sp., had been reporting have 90-100% antibiotic removal efficiency. The integration of bioelectrochemical systems and genetically engineered prokaryotic algal species offer promising avenues for improving antibiotic removal in the future. Overall, this review highlights the need for tenacious research and development of algae-based technologies to reduce antibiotic contamination in aquatic environments, for holistic good.

Unleashing the power of polymeric nanoparticles - Creative triumph against antibiotic resistance: A review

Antibiotic resistance (ABR) poses a universal concern owing to the widespread use of antibiotics in various sectors. Nanotechnology emerges as a promising solution to combat ABR, offering targeted drug delivery, enhanced bioavailability, reduced toxicity, and stability. This comprehensive review explores concepts of antibiotic resistance, its mechanisms, and multifaceted approaches to combat ABR. The review provides an in-depth exploration of polymeric nanoparticles as advanced drug delivery systems, focusing on strategies for targeting microbial infections and contributing to the fight against ABR. Nanoparticles revolutionize antimicrobial approaches, emphasizing passive and active targeting. The role of various molecules, including small molecules, antimicrobial peptides, proteins, carbohydrates, and stimuli-responsive systems, is being explored in recent research works. The complex comprehension mechanisms of ABR and strategic use of nanotechnology present a promising avenue for advancing antimicrobial tactics, ensuring treatment efficacy, minimizing toxic effects, and mitigating development of ABR. Polymeric nanoparticles, derived from natural or synthetic polymers, are crucial in overcoming ABR. Natural polymers like chitosan and alginate exhibit inherent antibacterial properties, while synthetic polymers such as polylactic acid (PLA), polyethylene glycol (PEG), and polycaprolactone (PCL) can be engineered for specific antibacterial effects. This comprehensive study provides a valuable source of information for researchers, healthcare professionals, and policymakers engaged in the urgent quest to overcome ABR.

Coverage of policies to improve antimicrobial stewardship in human medicine in low and middle income countries: results from the Global Survey of Experts on Antimicrobial Resistance

BACKGROUND

Antimicrobial resistance (AMR) constitutes a major threat to global health. While antimicrobial misuse or overuse is one of the main drivers for AMR, little is known about the extent to which antibiotic misuse is due to a lack of national government-led efforts to enforce rational use in low and middle-income countries (LMICs).

METHODS

To assess antimicrobial stewardship and national implementation measures currently in place for optimizing antimicrobial use and for slowing the spread of AMR, we invited public health experts from 138 LMICs to participate in a Global Survey of Experts on Antimicrobial Resistance (GSEAR). Key coverage measures, as reported by experts, were compared across countries and also juxtaposed with estimates collected in the 2020-21 World Health Organization-organized Tripartite AMR Country Self-Assessment Survey (TrACSS).

RESULTS

A total of 352 completed surveys from 118 LMICs were analysed. Experts in 67% of the surveyed countries reported a national action plan (NAP) on AMR, 64% reported legislative policies on antimicrobial use, 58% reported national training programs for health professionals, and 10% reported national monitoring systems for antimicrobials. 51% of LMICs had specific targeted policies to limit the sale and use of protected or reserve antibiotics. While 72% of LMICs had prescription requirements for accessing antibiotics, getting antibiotics without a prescription was reported to be possible in practice in 74% of LMICs. On average, country efforts reported in TrACSS were substantially higher than those seen in GSEAR.

CONCLUSIONS

In many LMICs, despite the existence of policies aimed at slowing down the spread of AMR, there are still significant gaps in their implementation and enforcement. Increased national efforts in the areas of enforcement and monitoring of antibiotic use as well as regular monitoring of national efforts are urgently needed to reduce inappropriate antibiotic use in LMICs and to slow the spread of AMR globally.

Versatile Fabrication of Biocompatible Antimicrobial Materials Enabled by Cationic Peptide Bundles

Antimicrobial peptides (AMPs) are expected to be an alternative promising solution to the global public health problem of antibiotic resistance due to their unique antimicrobial mechanism. However, extensive efforts are still needed to improve the shortcomings of traditional AMPs, such as rapid proteolysis, hemolysis, slow response, toxicity, etc., by exploring AMP-based new antimicrobial strategies. Here, we develop cationic peptide bundles into novel antimicrobial architectures that can rapidly kill multiple types of bacteria including drug-resistant bacteria. Remarkably, cationic peptide bundles can be used as polymerization units to cross-link with other polymers through simple two-component polymerization to produce diverse antimicrobial materials. For the proof of concept, three materials were fabricated and investigated, including an antimicrobial hydrogel that can significantly accelerate the healing of infected wounds, a multifunctional antimicrobial bioadhesive that shows promise in antimicrobial coatings for medical devices, and a photo-cross-linked antimicrobial gelatin hydrogel with broad application potential. The integration of antimicrobial units into the materials' backbone endows their biocompatibility. Cationic peptide bundles not only represent a new antimicrobial strategy but also provide a versatile and promising processing method to create diversified, multifunctional, and biocompatible antimicrobial materials.

Antibiotic Resistance & Extended-Spectrum ß-Lactamase Production in Clinical and Non-Clinical Isolates in Tabuk

The increasing prevalence of antibiotic resistance, driven by the production of extended-spectrum beta-lactamases (ESBLs), presents a critical challenge to current medical treatments, particularly in clinical settings. Understanding the distribution and frequency of ESBL-producing bacteria is essential for developing effective control strategies. This study investigated the antibiotic resistance and extended-spectrum beta-lactamase (ESBL) production in bacterial isolates in clinical and non-clinical (food) specimens in Tabuk, KSA. A total of 57 bacterial isolates were analysed, with E. coli and Pseudomonas sp. being the most prevalent. High resistance rates were observed, particularly against third-generation cephalosporins in clinical isolates. ESBL screening revealed a significant prevalence in clinical samples (58.3%), with E. coli showing the highest positivity. Conversely, only a low percentage of food isolates were ESBL positive. Molecular analysis confirmed the presence of various ESBL genes, with blaCTX-M being the most frequent, predominantly found in clinical isolates. This study highlights the concerning levels of antibiotic resistance and ESBL production in the region, emphasising the need for effective infection control measures and prudent antibiotic use.

Mangosteen extract reduces the bacterial load of eggshell and improves egg quality

The increasing emergence and spread of antibiotic resistance accelerate the desire for antibiotic alternatives. Plant extracts have emerged as a promising and relatively unexplored area of research as potential substitutes. Herein, we investigated the prevalence and distribution patterns of bacteria on egg surfaces and evaluated the inhibitory effects of mangosteen extract on these surface bacteria. In addition, we examined the antioxidant activity and egg quality in improving the ability of mangosteen extract. The results showed that the predominant bacteria isolated from eggshells were Gram-positive, with Staphylococcus and Micrococcus as the dominant genera. Notably, mangosteen extract exhibited significant bactericidal activity, effectively inhibiting Gram-positive bacteria on the surface of chicken eggshells. Moreover, the supplementation of mangosteen extract in the feed of laying hens yielded a noteworthy improvement in egg quality, accompanied by positively shaped structure and function of microbial communities on the egg surface and in the feces. Collectively, our findings suggested that mangosteen extract was an effective alternative to traditional antibiotics, offering valuable insights for animal husbandry development.

High Therapeutic Index α-Helical AMPs and Their Therapeutic Potential on Bacterial Lung and Skin Wound Infections

Antimicrobial peptides (AMPs) possess strong antibacterial activity and low drug resistance, making them ideal candidates for bactericidal drugs for addressing the issue of traditional antibiotic resistance. In this study, a template (G(XXKK)nI, G = Gly; X = Leu, Ile, Phe, or Trp; n = 2, 3, or 4; K = Lys; I = Ile.) was employed for the devised of a variety of novel α-helical AMPs with a high therapeutic index. The AMP with the highest therapeutic index, WK2, was ultimately chosen following a thorough screening process. It demonstrates broad-spectrum and potent activity against both standard and multidrug-resistant bacteria, while also showing low hemolysis and rapid and efficient time-kill kinetics. Additionally, WK2 exhibits excellent efficacy in treating mouse models of Klebsiella pneumonia-induced lung infections and methicillin-resistant Staphylococcus aureus (MRSA)-induced skin wound infections while demonstrating good safety profiles in vivo. In conclusion, the template-based design methodology for novel AMPs with high therapeutic indices offers new insights into addressing antibiotic resistance problems. WK2 represents a promising antimicrobial agent.

Effects of Organic Soil Amendments on Antimicrobial-Resistant Bacteria in Urban Agriculture Environments

Biological soil amendments of animal origin (BSAAOs) are widely used in urban agriculture to improve soil quality. Although BSAAO use is regulated due to risks for introducing foodborne pathogens, effects on antimicrobial-resistant (AMR) bacteria are not well established. Here, we aimed to explore the impacts of BSAAOs on levels of resident AMR bacteria in leafy vegetable production environments (i.e., kale, lettuce, chard, cabbage) across urban farms and community gardens in the greater Washington D.C. area (n = 7 sites). Leaf tissue (LT), root zone soil (RZS; amended soil in crop beds), and bulk soil (BS; site perimeter) were collected and analyzed for concentrations of total heterotrophic bacteria (THB), ampicillin (Amp) or tetracycline (Tet) resistant THB, and coliforms. As expected, amended plots harbored significantly higher concentrations of THB than bulk soil (P < 0.001). The increases in total bacteria associated with reduced fractions of Tet-resistant bacteria (P = 0.008), as well as case-specific trends for reduced fractions of Amp-resistant bacteria and coliforms. Site-to-site variation in concentrations of AMR bacteria in soil and vegetable samples reflected differences in land history and crop management, while within-site variation was associated with specific amendment sources, as well as vegetable type and cultivar. Representative isolates of the AMR bacteria and coliforms were further screened for multidrug resistance (MDR) phenotypes, and a high frequency was observed for the former. In amended soils, as the soil pH (range 6.56-7.80) positively correlated with the fraction of Tet-resistant bacteria (rho = 0.529; P < 0.001), crop management strategies targeting pH may have applications to control related risks. Overall, our findings demonstrate that soil amendments promote soil bacteria concentrations and have important implications for limiting the spread of AMR bacteria, at least in the urban landscape.

Antimicrobial, Antiradical Activity, and X-Ray Fluorescence Spectroscopy Analysis of Aloe otallensis Plant Used in Traditional Medicine in Southern Ethiopia

Medicinal plants have a long history of treating diseases in animals and humans in Ethiopia. Nevertheless, not enough research has been done on the antibacterial properties and possible bioactive components of the majority of medicinal plants. Therefore, this study was concerned with the evaluation of the percentage yield, phytochemical, antimicrobial, antifungal, MIC, antiradical activities, phenolic content, and X-ray fluorescence spectroscopy (XRF) analysis of A. otallensis plant extracts. The mean values of antimicrobial, antifungal, MIC, antiradical, phenolic content, and XRF analysis were reported as mean ± standard deviation. The solvent methanol showed a higher degree of yield in leaf and root extract which was 8.45 (22.27%) and 3.12 g (15.58%), respectively, while distilled water extract of leaf and root showed less degree of yield which was 0.22 g (1.10%) and 0.42 g (2.1%), respectively. Qualitative phytochemical analyses of the plant parts have revealed the presence of various components of metabolites like alkaloids, flavonoids, phenol, saponins, tannins, steroids, steroids, terpenoids, triterpenoids, glycosides, anthraquinones, diterpenes, phytosterols, and phlobatannals. A. otallensis gel extracts had shown significant antibacterial and antifungal activity against the test bacterial and fungus, respectively. Moreover, the methanolic gel extracts of A. otallensis demonstrated notable antiradical activity than the leaf and the root. The highest value of phenolic content was obtained in A. otallensis; gel, leaf, and root extract which was 61.9 ± 0.5 mg/g, 53.6 ± 0.3 mg/g, and 51.6 ± 0.6 mg/g, respectively. In this study, twelve elements in the plant parts of A. otallensis were determined using XRF spectroscopy. Overall, this research contributes to the understanding of the pharmacological potential of A. otallensis and highlights the importance of further research into its medicinal properties. The results provide valuable insights into the use of medicinal plants to treat diseases and support the development of natural therapeutics.

A systematic review of diabetic foot infections: pathogenesis, diagnosis, and management strategies

Background

Diabetic foot infection represents a significant complication of diabetes mellitus, contributing substantially to morbidity, mortality, and healthcare expenditure worldwide. Accurate diagnosis relies on a comprehensive assessment integrating clinical evaluation, imaging studies, and microbiological analysis. Management necessitates a multidisciplinary approach, encompassing surgical intervention, antimicrobial therapy, and advanced wound care strategies. Preventive measures are paramount in reducing the incidence and severity, emphasizing patient education, regular foot screenings, and early intervention.

Methods

The researchers performed a systematic review of literature using PUBMED MESH keywords. Additionally, the study was registered in the International Prospective Register of Systematic Reviews at the Center for Reviews and Dissemination, University of York (CRD42021277788). This review provides a comprehensive overview of the microbial spectrum and antibiotic susceptibility patterns observed in diabetic foot infections.

Results

The search through the databases finally identified 13 articles with 2545 patients from 2021 to 2023. Overall, the predominant Gram-positive microbial species isolated were Staphylococcus aureus, Enterococcus fecalis, Streptococcus pyogenes, Streptococcus agalactiae, and Staphylococcus epidermidis. Whereas the predominant Gram-negative included Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Pseudomonas aeruginosa.

Conclusion

Diabetic foot infections represent a complex and multifaceted clinical entity, necessitating a holistic approach to diagnosis, management, and prevention. Limited high-quality research data on outcomes and the effectiveness of guideline recommendations pose challenges in updating and refining existing DFI management guidelines.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021277788, identifier CRD42021277788.

Antimicrobial prescribing in referral hospitals in Timor-Leste: results of the first two national point prevalence surveys, 2020-21

Objectives

To describe antimicrobial use (AMU) in patients admitted to hospitals in Timor-Leste.

Methods

In 2020 and 2021, we undertook antimicrobial prescribing point prevalence surveys across all six hospitals in Timor-Leste (one national and five municipal) to describe AMU and appropriateness in admitted patients.

Results

In 2020, 291/394 (73.9%) surveyed patients had been prescribed antimicrobials, compared with 260/403 (64.5%) in 2021 (P = 0.004). Most (309/551; 56.1%) were prescribed one antimicrobial, and 179/551 (32.5%) were prescribed two. The most commonly prescribed antibiotics were ceftriaxone (38.5% in 2020, 41.5% in 2021) and ampicillin (35.7% in 2020, 32.3% in 2021), followed by gentamicin, metronidazole and cloxacillin. Reserve antibiotics like meropenem and vancomycin were minimally used. Of all antimicrobial prescriptions, 70.8% were deemed appropriate in 2020 and 69.1% in 2021. Antimicrobial prescriptions for surgical and post-partum prophylaxis were frequently deemed inappropriate [37/50 (74.0%) and 39/44 (88.6%) prescriptions, respectively].

Conclusions

Most patients admitted to hospital in Timor-Leste are prescribed antimicrobials, and approximately one-third of these prescriptions are inappropriate. However, this was in the context of limited local guideline availability at the time of surveys and limited microbiological culture capacity outside of the capital, Dili. Improved microbiological guidance, iterative guideline revisions based on local antimicrobial resistance (AMR) surveillance data, and enhanced stewardship activities including further point prevalence studies, could improve antimicrobial use, optimize patient outcomes and reduce AMR in Timor-Leste.

Building a Logic Model to Foster Engagement and Learning Using the Case of a Province-Wide Multispecies Antimicrobial Use Monitoring System

Successfully designing and implementing a program is complex; it requires a reflexive balance between the available resources and the priorities of various stakeholders, both of which change over time. Logic models are theory-based evaluation approaches used to identify and address key challenges of a program. This article describes the process of building a logic model on advanced theories in complexity studies. The models aim to support a province-wide multispecies monitoring system of antimicrobial use (AMU), designed in collaboration with the animal health sector in Quebec (Canada). Based on a rigorous theoretical foundation, the logic model is built in three steps: (1) mapping, a narrative review of literature on similar programs in other jurisdictions; (2) framing, iterative consultations with project members to elaborate the logic model; (3) shaping, hypotheses based on the logic model. The model emerges from the reflexive balancing of current scientific knowledge and empirical insights to gather relevant information about stakeholders from interdisciplinary experts that led a 3-year consensus-building process within the community. Recognizing the challenge of unpacking theories for practical use, we illustrate how the process of an "open" logic model building could enable governance coordination in complex processes. Logic models are useful for evaluating public, private, and academic partnerships in One Health programs that characterize an adaptive governance process.

Coexistence of multidrug resistance and ESBL encoding genes - blaTEM, blaSHV, and blaCTX-M; its amplification and dispersion in the environment via municipal wastewater treatment plant

Municipal wastewater treatment plants (MWWTPs) are a global source of antibiotic resistance genes (ARGs), collecting wastewater from a variety of sources, including hospital wastewater, domestic wastewater, runoff from agricultural and livestock farms, etc. These sources are contaminated with organic and inorganic pollutants, ARGs and antibiotic-resistant bacteria (ARB). Such pollutants aided eutrophication and encouraged bacterial growth. During bacterial growth horizontal gene transfer (HGT) and vertical gene transfer (VGT) of ARGs and extended-spectrum β-lactamase (ESBL) encoding genes may facilitate, resulting in the spread of antibiotic resistance exponentially. The current study investigated the prevalence of multidrug resistance (MDR) and ESBL encoding genes in various treatment units of MWWTP and their spread in the environment. A total of three sampling sites (BUT, BRO, and BFB) were chosen, and 33 morphologically distinct bacterial colonies were isolated. 14 of the 33 isolates tested positive for antibiotic resistance and were further tested for the coexistence of MDR and ESBL production. The selected 14 isolates showed the highest resistance to trimethoprim (85.71%), followed by ciprofloxacin, azithromycin, and ampicillin (71.42%), tetracycline (57.14%), and vancomycin, gentamicin, and colistin sulphate (50%). A total of 9 isolates (64.28%) were phenotypically positive for ESBL production (BUT2, BUT3, BUT5, BRO1, BRO2, BRO3, BRO4, BRO5 and BFB1). The molecular detection of ESBL encoding genes, i.e. blaTEM, blaSHV, and blaCTX-M was carried out. The most prevalent gene was blaTEM (69.23%), followed by blaSHV (46.15%), and blaCTX-M (23.07%). In this study, 9 isolates (64.28%) out of 14 showed the coexistence of MDR and ESBL encoding genes, namely BUT3, BUT4, BUT5, BUT6, BUT7, BRO1, BRO2, BRO4, and BFB1. The coexistence of ESBL encoding genes and resistance to other antibiotic classes exacerbates human health and the environment.

An integrated in silico approach for the identification of novel potential drug target and chimeric vaccine against Neisseria meningitides strain 331401 serogroup X by subtractive genomics and reverse vaccinology

Neisseria meningitidis, commonly known as the meningococcus, leads to substantial illness and death among children and young adults globally, revealing as either epidemic or sporadic meningitis and/or septicemia. In this study, we have designed a novel peptide-based chimeric vaccine candidate against the N. meningitidis strain 331,401 serogroup X. Through rigorous analysis of subtractive genomics, two essential cytoplasmic proteins, namely UPI000012E8E0(UDP-3-O-acyl-GlcNAc deacetylase) and UPI0000ECF4A9(UDP-N-acetylglucosamine acyltransferase) emerged as potential drug targets. Additionally, using reverse vaccinology, the outer membrane protein UPI0001F4D537 (Membrane fusion protein MtrC) identified by subcellular localization and recognized for its known indispensable role in bacterial survival was identified as a novel chimeric vaccine target. Following a careful comparison of MHC-I, MHC-II, T-cell, and B-cell epitopes, three epitopes derived from UPI0001F4D537 were linked with three types of linkers-GGGS, EAAAK, and the essential PADRE-for vaccine construction. This resulted in eight distinct vaccine models (V1-V8). Among them V1 model was selected as the final vaccine construct. It exhibits exceptional immunogenicity, safety, and enhanced antigenicity, with 97.7 % of its residues in the Ramachandran plot's most favored region. Subsequently, the vaccine structure was docked with the TLR4/MD2 complex and six different HLA allele receptors using the HADDOCK server. The docking resulted in the lowest HADDOCK score of 39.3 ± 9.0 for TLR/MD2. Immune stimulation showed a strong immune response, including antibodies creation and the activation of B-cells, T Cytotoxic cells, T Helper cells, Natural Killer cells, and interleukins. Furthermore, the vaccine construct was successfully expressed in the Escherichia coli system by reverse transcription, optimization, and ligation in the pET-28a (+) vector for the expression study. The current study proposes V1 construct has the potential to elicit both cellular and humoral responses, crucial for the developing an epitope-based vaccine against N. meningitidis strain 331,401 serogroup X.

Prevalence of antibiotic use for childhood diarrhoea in Uganda after an ORS scale-up intervention: a repeated cross-sectional study

BACKGROUND

Diarrhoea kills 500,000 children every year despite availability of cheap and effective treatment. In addition, a large number are inappropriately treated with antibiotics, which do not benefit the patient but can contribute to the development of antibiotic resistance. We investigated whether the prevalence of antibiotic use among children under the age of five with diarrhoea in Uganda changed following a national intervention to increase the use of oral rehydration salts (ORS), and whether any socioeconomic characteristics were associated with antibiotic use.

METHODS

A cross-sectional survey was conducted among caregivers of children under the age of five and among private health care providers and drug sellers in Uganda in 2014. This was compared to a similar survey among private health care providers, and the national demographic and health survey in Uganda in 2016. Logistic regression was used to find associations between antibiotic use and socioeconomic characteristics, and chi-square test and independent sample t-test were used to find significant differences between groups.

RESULTS

The prevalence of antibiotic use among children under the age of five with diarrhoea in Uganda decreased from 30.5% in 2014 to 20.0% (p < 0.001) in 2016. No associations between socioeconomic characteristics and the use of antibiotics were significant in both 2014 and 2016.

CONCLUSIONS

The use of antibiotics in children with diarrhoeal disease decreased significantly in Uganda between 2014 and 2016. However, the extent of the contribution of the ORS scale-up programme to this decrease cannot be determined from this study.

De novo synthetic antimicrobial peptide design with a recurrent neural network

Antibiotic resistance is recognized as an imminent and growing global health threat. New antimicrobial drugs are urgently needed due to the decreasing effectiveness of conventional small-molecule antibiotics. Antimicrobial peptides (AMPs), a class of host defense peptides, are emerging as promising candidates to address this need. The potential sequence space of amino acids is combinatorially vast, making it possible to extend the current arsenal of antimicrobial agents with a practically infinite number of new peptide-based candidates. However, mining naturally occurring AMPs, whether directly by wet lab screening methods or aided by bioinformatics prediction tools, has its theoretical limit regarding the number of samples or genomic/transcriptomic resources researchers have access to. Further, manually designing novel synthetic AMPs requires prior field knowledge, restricting its throughput. In silico sequence generation methods are gaining interest as a high-throughput solution to the problem. Here, we introduce AMPd-Up, a recurrent neural network based tool for de novo AMP design, and demonstrate its utility over existing methods. Validation of candidates designed by AMPd-Up through antimicrobial susceptibility testing revealed that 40 of the 58 generated sequences possessed antimicrobial activity against Escherichia coli and/or Staphylococcus aureus. These results illustrate that AMPd-Up can be used to design novel synthetic AMPs with potent activities.

Exceptions to the rule: When does resistance evolution not undermine antibiotic therapy in human bacterial infections?

The use of antibiotics to treat bacterial infections often imposes strong selection for antibiotic resistance. However, the prevalence of antibiotic resistance varies greatly across different combinations of pathogens and drugs. What underlies this variation? Systematic reviews, meta-analyses, and literature surveys capable of integrating data across many studies have tried to answer this question, but the vast majority of these studies have focused only on cases where resistance is common or problematic. Yet much could presumably be learned from the cases where resistance is infrequent or absent. Here we conducted a literature survey and a systematic review to study the evolution of antibiotic resistance across a wide range of pathogen-by-drug combinations (57 pathogens and 53 antibiotics from 15 drug classes). Using Akaike information criterion-based model selection and model-averaged parameter estimation we explored 14 different factors posited to be associated with resistance evolution. We find that the most robust predictors of high resistance are nosocomial transmission (i.e., hospital-acquired pathogens) and indirect transmission (e.g., vector-, water-, air-, or vehicle-borne pathogens). While the former was to be expected based on prior studies, the positive correlation between high resistance frequencies and indirect transmission is, to our knowledge, a novel insight. The most robust predictor of low resistance is zoonosis from wild animal reservoirs. We also found partial support that resistance was associated with pathogen type, horizontal gene transfer, commensalism, and human-to-human transmission. We did not find support for correlations between resistance and environmental reservoirs, mechanisms of drug action, and global drug use. This work explores the relative explanatory power of various pathogen and drug factors on resistance evolution, which is necessary to identify priority targets of stewardship efforts to slow the spread of drug-resistant pathogens.

Cubosome lipid nanocarriers for delivery of ultra-short antimicrobial peptides

HYPOTHESIS

Although antimicrobial peptides (AMPs) are a promising class of new antibiotics, their inherent susceptibility to degradation requires nanocarrier-mediated delivery. While cubosome nanocarriers have been extensively studied for delivery of AMPs, we do not currently understand why cubosome encapsulation improves antimicrobial efficacy for some compounds but not others. This study therefore aims to investigate the link between the mechanism of action and permeation efficiency of the peptides, their encapsulation efficacy, and the antimicrobial activity of these systems.

EXPERIMENTS

Encapsulation and delivery of Indolicidin, and its ultra-short derivative, Priscilicidin, were investigated using SAXS, cryo-TEM and circular dichroism. Molecular dynamics simulations were used to understand the loading of these peptides within cubosomes. The antimicrobial efficacy was assessed against gram-negative (E. coli) and gram-positive (MRSA) bacteria.

FINDINGS

A high ionic strength solution was required to facilitate high loading of the cationic AMPs, with bilayer encapsulation driven by tryptophan and Fmoc moieties. Cubosome encapsulation did not improve the antimicrobial efficacy of the AMPs consistent with their high permeation, as explained by a recent 'diffusion to capture model'. This suggests that cubosome encapsulation may not be an effective strategy for all antimicrobial compounds, paving the way for improved selection of nanocarriers for AMPs, and other antimicrobial compounds.

Metal coordination governs the antimicrobial efficacy of calcitermin derivatives

Antimicrobial peptides are promising alternatives to classical antibiotics. Their microbicidal activity can arise from different mechanisms, one of which is known as nutritional immunity and has metal micronutrients and metal-binding biomolecules as its main players. Calcitermin is an antimicrobial peptide and an effective metal chelator. Its properties as an antibacterial and anti-Candida agent have been recently studied both as a free peptide and in the presence of zinc and copper ions, with which it forms stable complexes. Calcitermin derivatives have also gained attention thanks to the possibility of improving their properties, like metal-binding affinity and/or stability in biological fluids, through ad hoc modifications of the native peptide sequence. In this work, the Ala-to-Ser substitutions close to the coordination site of calcitermin have been introduced to study the impact on the biological activity and metal-binding properties. Our results show that metal coordination has a clear impact on the bioactivity of the studied compounds, to the point that the truncated fragment of calcitermin, solely containing the main metal-binding residues, also shows antimicrobial activity.

Unraveling bacterial stress responses: implications for next-generation antimicrobial solutions

The accelerated spread of antimicrobial-resistant bacteria has caused a serious health problem and rendered antimicrobial treatments ineffective. Innovative approaches are crucial to overcome the health threat posed by resistant pathogens and prevent the emergence of untreatable infections. Triggering stress responses in bacteria can diminish susceptibility to various antimicrobials by inducing resistance mechanisms. Therefore, a thorough understanding of stress response control, especially in relation to antimicrobial resistance, offers valuable perspectives for innovative and efficient therapeutic approaches to combat antimicrobial resistance. The aim of this study was to evaluate the stress responses of 8 different bacteria by analyzing reporter metabolites, around which significant alterations were observed, using a pathway-driven computational approach. For this purpose, the transcriptomic data that the bacterial pathogens were grown under 11 different stress conditions mimicking the human host environments were integrated with the genome-scale metabolic models of 8 pathogenic species (Enterococcus faecalis OG1R, Escherichia coli EPEC O127:H6 E2348/69, Escherichia coli ETEC H10407, Escherichia coli UPEC 536, Klebsiella pneumoniae MGH 78578, Pseudomonas aeruginosa PAO1, Staphylococcus aureus MRSA252, and Staphylococcus aureus MSSA476). The resulting reporter metabolites were enriched in multiple metabolic pathways, with cofactor biosynthesis being the most important. The results of this study will serve as a guide for the development of antimicrobial agents as they provide a first insight into potential drug targets.

The Global Burden of Sepsis and Septic Shock

A dysregulated host response to infection causes organ dysfunction in sepsis and septic shock, two potentially fatal diseases. They continue to be major worldwide health burdens with high rates of morbidity and mortality despite advancements in medical care. The goal of this thorough review was to present a thorough summary of the current body of knowledge about the prevalence of sepsis and septic shock worldwide. Using widely used computerized databases, a comprehensive search of the literature was carried out, and relevant studies were chosen in accordance with predetermined inclusion and exclusion criteria. A narrative technique was used to synthesize the data that were retrieved. The review's conclusions show how widely different locations and nations differ in terms of sepsis and septic shock's incidence, prevalence, and fatality rates. Compared to high-income countries (HICs), low- and middle-income countries (LMICs) are disproportionately burdened more heavily. We talk about risk factors, comorbidities, and difficulties in clinical management and diagnosis in a range of healthcare settings. The review highlights the need for more research, enhanced awareness, and context-specific interventions in order to successfully address the global burden of sepsis and septic shock.

Healthcare as a driver, reservoir and amplifier of antimicrobial resistance: opportunities for interventions

Antimicrobial resistance (AMR) is a global health challenge that threatens humans, animals and the environment. Evidence is emerging for a role of healthcare infrastructure, environments and patient pathways in promoting and maintaining AMR via direct and indirect mechanisms. Advances in vaccination and monoclonal antibody therapies together with integrated surveillance, rapid diagnostics, targeted antimicrobial therapy and infection control measures offer opportunities to address healthcare-associated AMR risks more effectively. Additionally, innovations in artificial intelligence, data linkage and intelligent systems can be used to better predict and reduce AMR and improve healthcare resilience. In this Review, we examine the mechanisms by which healthcare functions as a driver, reservoir and amplifier of AMR, contextualized within a One Health framework. We also explore the opportunities and innovative solutions that can be used to combat AMR throughout the patient journey. We provide a perspective on the current evidence for the effectiveness of interventions designed to mitigate healthcare-associated AMR and promote healthcare resilience within high-income and resource-limited settings, as well as the challenges associated with their implementation.

Anomaly detection in the veterinary antibiotic prescription surveillance system (IS ABV)

Antibiotic resistance is one of the major concerns in veterinary and human medicine and poses a considerable threat to both human and animal health. It has been shown that over- or misuse of antibiotics is one of the primary drivers of antibiotic resistance. To develop the surveillance of antibiotic use, Switzerland introduced the "Informationssystem Antibiotika in der Veterinärmedizin" (IS ABV) in 2019, mandating electronic registration of antibiotic prescriptions by all veterinarians in Switzerland. However, initial data analysis revealed a considerable amount of implausible data entries, potentially compromising data quality and reliability. These anomalies may be caused by input errors, inaccuracies, incorrect or aberrant master data or data transmission and make analysis impossible. To address this issue efficiently, we propose a two-stage anomaly detection framework utilizing machine learning algorithms. In this study, our primary focus was on cattle treatments with either single or group therapy, as they were the species with the highest prescription volume. However, not all outliers are necessarily incorrect; some may be legitimate but unusual antibiotic treatments. Thus, expert review plays a crucial role in distinguishing outliers, that are correct from actual errors. Initially, relevant prescription variables were extracted and pre-processed with a custom-built scaler. A set of unsupervised algorithms calculated the probability of each data point and identified the most likely outliers. In collaboration with experts, we annotated anomalies and established anomaly thresholds for each production type and active substance. These expert-annotated labels were then used to fine-tune the final supervised classification algorithms. With this methodology, we identified 22,816 anomalies from a total of 1,994,170 prescriptions in cattle (1.1 %). Cattle with no further specified production type had the most (2 %) anomalies with 7758 out of 379,995. The anomalies were consistently identified and comprised prescriptions with too high and too low dosages. Random Forest achieved a ROC-AUC score of 0.994, (95 % CI: 0.992, 0.995) and a F1-Score of 0.962 (95 % CI: 0.958, 0.966) for single treatments. The versatility of this framework allows its adaptation to other species within IS ABV and potentially to other prescription-based surveillance systems. If applied regularly to uploaded prescriptions, it should reduce input errors over time, improving the validity of the data in the long term.

Tailoring zirconia surface topography via femtosecond laser-induced nanoscale features: effects on osteoblast cells and antibacterial properties

The performance and long-term durability of dental implants hinge on the quality of bone integration and their resistance to bacteria. This research aims to introduce a surface modification strategy for zirconia implants utilizing femtosecond laser ablation techniques, exploring their impact on osteoblast cell behavior and bacterial performance, as well as the integral factors influencing the soft tissue quality surrounding dental implants. Ultrafast lasers were employed to craft nanoscale groove geometries on zirconia surfaces, with thorough analyses conducted using x-ray diffraction, scanning electron microscopy, atomic force microscopy, and water contact angle measurements. The study evaluated the response of human fetal osteoblastic cell lines to textured zirconia ceramics by assessing alkaline phosphatase activity, collagen I, and interleukin 1βsecretion over a 7 day period. Additionally, the antibacterial behavior of the textured surfaces was investigated usingFusobacterium nucleatum, a common culprit in infections associated with dental implants. Ciprofloxacin (CIP), a widely used antibacterial antibiotic, was loaded onto zirconia ceramic surfaces. The results of this study unveiled a substantial reduction in bacterial adhesion on textured zirconia surfaces. The fine biocompatibility of these surfaces was confirmed through the MTT assay and observations of cell morphology. Moreover, the human fetal osteoblastic cell line exhibited extensive spreading and secreted elevated levels of collagen I and interleukin 1βin the modified samples. Drug release evaluations demonstrated sustained CIP release through a diffusion mechanism, showcasing excellent antibacterial activity against pathogenic bacteria, includingStreptococcus mutans, Pseudomonas aeruginosa, andEscherichia coli.

Whole-genome sequencing of multidrug-resistant Escherichia coli causing urinary tract infection in an immunocompromised patient: a case report

BACKGROUND

Escherichia coli is a major human pathogen responsible for a broad range of clinical illnesses. It has been linked to endemic and epidemic nosocomial diseases caused by multidrug-resistant pathogens in Sudan as well as throughout the globe.

CASE PRESENTATION

A 76-year-old African woman arrived at Saad Rashwan Medical Centre complaining of backaches and discomfort during urination. Throughout the preceding 5 years, the patient had recurrent urinary tract infections. Following overnight incubation at 37 °C, Escherichia coli was found in her midstream urine specimen on cysteine lactose electrolyte deficient agar media. Minimum inhibitory concentration (colorimetric/turbidimetric method) was employed to test a wide range of antimicrobial drugs against this bacterial strain, and the results revealed significant multidrug resistance. QIAamp® DNA Mini Kit was used to obtain DNA Template from the purified Escherichia coli (Qiagen, Hilden, Germany). The bacterial whole-genome sequence was done by Novogene company (Hong Kong) using Illumina HiSeq 2500 (Illumina, San Diego, CA, USA), followed by whole genome reconstructions, and identification of antibiotic-resistant genes. Phylogenetic analysis revealed that our strain was related to the Escherichia coli DSM30083 ( genome sequence ID: CP033092.2) from the USA. Our strain possessed the following antimicrobial-resistant genes: aminoglycoside (kdpE, baeR, cpxA, aadA5), nitroimidazole (msbA), phosphonic acid (mdtG), tetracycline (emrY), macrolide, penam, tetracycline, (evgA, TolC, H-NS), fluoroquinolone, cephalosporin, glycylcycline, penam, tetracycline, rifamycin, phenicol antibiotic, disinfecting agents and antiseptics (acrB; marA), sulfonamide (sul1), macrolide (Mrx), cephalosporin, penam (CTX-M-15), carbapenem, cephalosporin, and penam (OXA-1).

CONCLUSION

This study found that the isolated Escherichia coli strain had varied antimicrobial resistance genes on the basis of whole-genome sequencing and phenotypic resistance analyses. Whole-genome sequencing is critical for control and preventative methods to battle the growing threat of antimicrobial resistance. A larger investigation is recommended for improved generalization of results.

New 1,3-diphenyl-1H-pyrazol-5-ols as anti-methicillin resistant Staphylococcus aureus agents: Synthesis, antimicrobial evaluation and in silico studies

In the present work, two hybrid series of pyrazole-clubbed pyrimidine and pyrazole-clubbed thiazole compounds 3-21 from 4-acetyl-1,3-diphenyl-1H-pyrazole-5(4H)-ole 1 were synthesized as novel antimicrobial agents. Their chemical structures were thoroughly elucidated in terms of spectral analyses such as IR, 1H NMR, 13C NMR and mass spectra. The compounds were in vitro evaluated for their antimicrobial efficiency against various standard pathogen strains, gram -ive bacteria (Pseudomonas aeruginosa, Klebsiella pneumonia), gram + ive bacteria (MRSA, Bacillus subtilis), and Unicellular fungi (Candida albicans) microorganisms. The ZOI results exhibited that most of the tested molecules exhibited inhibition potency from moderate to high. Where compounds 7, 8, 12, 13 and 19 represented the highest inhibition potency against most of the tested pathogenic microbes comparing with the standard drugs. In addition, the MIC results showed that the most potent molecules 7, 8, 12, 13 and 19 showed inhibition effect against most of the tested microbes at low concentration. Moreover, the docking approach of the newly synthesized compounds against DNA gyrase enzyme was performed to go deeper into their molecular mechanism of antimicrobial efficacy. Further, computational investigations to calculate the pharmacokinetics parameters of the compounds were performed. Among them 7, 8, 12, 13 and 19 are the most potent compounds revealed the highest inhibition efficacy against most of the tested pathogenic microbes comparing with the standard drugs.

Prophylactic antibiotics in sialendoscopy: a randomized clinical trial

OBJECTIVE

Antibiotics have been prescribed routinely in sialendoscopy procedures to reduce the risk of postoperative infection, despite the limited evidence supporting this practice. Being necessary to assess the need for antibiotics in Sialendoscopy, aiming to provide evidence-based guidance to clinicians regarding antibiotic administration in this procedure.

MATERIALS & METHOD

A prospective, randomized, double-blind, controlled clinical trial to evaluate the of prophylactic antibiotics in Sialendoscopy was designed.

RESULTS

A total of 80 patients were included in this study, including 57 females (71.8%) and 23 males (28.8%). In terms of prophylaxis, 36 patients (45%) received prophylactic treatment, and 44 patients (55%) did not. The occurrence of infectious events was observed in 2 patients (5.6%) with prophylaxis and 4 patients (9.1%) without prophylaxis. However, this difference was not statistically significant (p = 0.556).

CONCLUSION

In conclusion, our prospective, randomized clinical trial aimed to address the debate regarding the use of prophylactic antibiotics in sialendoscopy. Our study's findings suggest that the routine use antibiotics may not be necessary to prevent postoperative infections in sialendoscopy procedures. These results have important implications for clinical practice, potentially reducing the unnecessary use of antibiotics and addressing concerns related to antibiotic resistance and adverse drug reactions.

Influence of the COVID-19 pandemic on the defined daily dose of antimicrobials in patients requiring elective and emergency surgical procedures

BACKGROUND

The COVID-19 pandemic has resulted in great incertitude and overwhelming changes in healthcare that have had a direct impact on antibiotic prescription. However, the influence of this pandemic on antibiotic consumption in patients undergoing surgery has not yet been analysed. The goal of this study was to analyse antimicrobial consumption and prescription in the same period of 2019 (pre-COVID-19), 2020 (beginning of the COVID-19 pandemic) and 2021 (established COVID-19) according to the DDD system in surgical patients at a tertiary-level hospital.

METHODS

A prospectively maintained database was analysed. All patients who underwent elective or emergency gastrointestinal surgery during the same period (2019, 2020 and 2021) were included. Those who received at least 1 of the 10 most frequently prescribed antimicrobials during those periods were analysed.

RESULTS

A total of 2975 patients were included in this study. In 2020, the number of procedures performed decreased significantly (653 versus 1154 and 1168 in 2020 versus 2019 and 2021, respectively; P = 0.005). Of all patients who underwent surgery during these periods, 45.08% received at least one of the antimicrobials studied (45.8% in 2020 versus 22.9% and 22.97% in 2019 and 2021, respectively; P = 0.005). Of these, 22.97% of the patients received a combination of these antimicrobials, with ceftriaxone/metronidazole being the most frequent. Hepato-Pancreato-Biliary and Liver Transplant, Emergency Surgery and Colorectal Surgery units had higher antibiotic consumption.

CONCLUSIONS

The COVID-19 pandemic has resulted in a significant decrease in surgical activity and higher post-operative antimicrobial prescription compared with previous and subsequent years.

Risk factors for colonisation by Multidrug-Resistant bacteria in critical care units

INTRODUCTION

Antimicrobial resistance is a major public health challenge recognised by the WHO as an urgent global healthcare concern. Patients in Intensive Care Units (ICUs) are particularly prone to colonisation and/or infection by multidrug-resistant organisms (MDROs).

OBJECTIVES

Delineate the epidemiological characteristics and risk factors for MDROs colonisation in mixed ICUs and Resuscitation Units by focusing on initial and nosocomial colonisation.

MATERIAL AND METHODS

A descriptive observational study with analytical elements. It uses the Zero-Resistance register from the Preventive Medicine Service of the Albacete General University Hospital (Spain) from April 2016 to December 2021. It identifies the risk factors for MDROs colonisation.

RESULTS

Of 7,541 cases, 61.0 % with initial colonisation had risk factors for MDROs versus 34.0 % not colonised upon hospitalisation (p < 0.001). Significant risk factors for initial colonisation included hospitalisation for ≥ 5 days within the last 3 months, prior MDROs colonisation/infection and institutionalization. No significant risk factor differences were found for nosocomial colonisation. An association between longer ICU stays and nosocomial colonisation (p < 0.001) was noted.

CONCLUSIONS

Significant risk factors for initial MDROs colonisation were hospitalisation for ≥ 5 days in the last 3 months, prior MDROs colonisation/infection and institutionalisation. Longer ICU stays increased the nosocomial colonisation risk.

IMPLICATIONS FOR CLINICAL PRACTICE

This study underscores the importance to early identify and manage patients at risk for MDROs colonisation in ICUs. By recognising factors (i.e. previous hospitalisations, existing colonisation or infection, impact of prolonged ICU stay), healthcare providers can implement targeted strategies to mitigate the spread of MDROs; e.g. enhanced surveillance, stringent infection control measures and judicious antibiotics use. Our findings highlight the need for a comprehensive approach to manage antimicrobial resistance in critical care settings to ultimately improve patient outcomes and reduce MDROs burden in hospitals.

Surveillance of Antimicrobial Resistance in the ECOWAS Region: Setting the Scene for Critical Interventions Needed

Antimicrobial resistance poses a significant challenge to public health globally, leading to increased morbidity and mortality. AMR surveillance involves the systematic collection, analysis, and interpretation of data on the occurrence and distribution of AMR in humans, animals, and the environment for action. The West African Health Organization, part of the Economic Community of West African States (ECOWAS), is committed to addressing AMR in the region. This paper examines the status of AMR surveillance in ECOWAS countries using available WHO data from the TrACSS survey and GLASS enrollments. The analysis reveals that while progress has been made, significant challenges remain. Twelve of the fifteen ECOWAS countries are enrolled in GLASS, and ten have developed national action plans (NAPs) for AMR. However, there is a need to ensure all countries fully implement their NAPs, continue reporting to GLASS, and use the data for evidence-based actions and decision making. Surveillance systems for AMR and antimicrobial consumption/use vary across countries with some demonstrating limited capacity. All countries, except Cabo Verde, reported having a reference laboratory for AMR testing. Strengthening laboratory capabilities, data management and use, and multisectoral coordination are crucial for effective AMR surveillance and response. Based on the findings and the regional context, it is essential to prioritize capacity building, data utilization, and the adoption of standardized guidelines for AMR surveillance. Collaboration among ECOWAS countries, the WAHO, and international partners is essential to address AMR comprehensively. Ensuring a consistent supply of essential antimicrobial medications and reagents is vital.

Evaluation of the Stereochemistry of Staphyloferrin A for Developing Staphylococcus-Specific Targeting Conjugates

Bacteria in the genus Staphylococcus are pathogenic and harmful to humans. Alarmingly, some Staphylococcus, such as methicillin-resistant S. aureus (MRSA) and vancomycin-resistant S. aureus (VRSA) have spread worldwide and become notoriously resistant to antibiotics, threatening and concerning public health. Hence, the development of new Staphylococcus-targeting diagnostic and therapeutic agents is urgent. Here, we chose the S. aureus-secreted siderophore staphyloferrin A (SA) as a guiding unit. We developed a series of Staphyloferrin A conjugates (SA conjugates) and showed the specific targeting ability to Staphylococcus bacteria. Furthermore, among the structural factors we evaluated, the stereo-chemistry of the amino acid backbone of SA conjugates is essential to efficiently target Staphylococci. Finally, we demonstrated that fluorescent Staphyloferrin A probes (SA-FL probes) could specifically target Staphylococci in complex bacterial mixtures.

Copper transporter protein (MctB) as a therapeutic target to elicit antimycobacterial activity against tuberculosis

Tuberculosis (TB) is a prehistoric infection and major etiologic agent of TB, Mycobacterium tuberculosis, which is considered to have advanced from an early progenitor species found in Eastern Africa. By the 1800s, there were approximately 800 to 1000 fatality case reports per 100,000 people in Europe and North America. This research suggests an In-silico study to identify potential inhibitory compounds for the target Mycobacterial copper transport protein (Mctb). ADME-based virtual screening, molecular docking, and molecular dynamics simulations were conducted to find promising compounds to modulate the function of the target protein. Four chemical compounds, namely Anti-MCT1, Anti-MCT2, Anti-MCT3 and Anti-MCT4 out of 1500 small molecules from the Diverse-lib of MTiOpenScreen were observed to completely satisfy Lipinski rule of five and Veber's rule. Further, significantly steady interactions with the MctB target protein were observed. Docking experiments have presented 9 compounds with less than -9.0 kcal/mol free binding energies and further MD simulation eventually gave 4 compounds having potential interactions and affinity with target protein and favorable binding energy ranging from -9.2 to -9.3 kcal/mol. We may propose these compounds as an effective candidate to reduce the growth of M. tuberculosis and may also assist present a novel therapeutic approach for Tuberculosis. In vivo and In vitro validation would be needed to proceed further in this direction.Communicated by Ramaswamy H. Sarma.

Antimicrobial Archetypes: Assessing the Knowledge, Attitude, and Practice (KAP) Trends in Antimicrobial Resistance (AMR) and Antimicrobial Stewardship Program (AMSP) Among Faculties, Residents, and Interns in a Tertiary Care Hospital

Background Antimicrobial resistance (AMR) is caused by inappropriate use of antimicrobials. India's high antibiotic use contributes significantly to AMR. Antimicrobial Stewardship Programs (AMSPs) are crucial for optimizing antimicrobial use. Knowledge, Attitude, and Practice (KAP) studies are essential for evaluating healthcare professionals' beliefs and conduct regarding AMR and AMSPs. Materials and methods A cross-sectional study at Saveetha Medical College and Hospital evaluated doctors' knowledge, attitudes, and practices regarding AMR and stewardship programs. The study involved 202 participants, including faculty members, postgraduates, and interns. Results The study involved 202 participants, with residents being the majority at 51.4%, followed by faculty at 26.7% and interns at 21.7%. Faculty members showed the highest overall knowledge, followed by residents and interns. Despite possessing knowledge, practitioners did not consistently implement their knowledge in their daily practices, with a statistically significant difference of p < 0.01. There was a substantial disparity in attitude between the departments, as evidenced by a statistically significant p-value of less than 0.01. Conclusion Positive trends in knowledge and attitudes exist, but there are areas for improvement in translating attitudes into clinical practices. There is a significant disparity among faculty members, residents, and interns, highlighting the urgent need for interventions to bridge the gap. Implementing antibiotic prescribing guidelines at the institutional level and enhancing knowledge, attitudes, and practices among healthcare professionals are crucial to addressing AMR.

28 NICUs participating in a quality improvement collaborative targeting early-onset sepsis antibiotic use

OBJECTIVE

There is widespread overuse of antibiotics in neonatal intensive care units (NICUs). The objective of this study was to safely reduce antibiotic use in participating NICUs by targeting early-onset sepsis (EOS) management.

STUDY DESIGN

Twenty-eight NICUs participated in this statewide multicenter antibiotic stewardship quality improvement collaborative. The primary aim was to reduce the total monthly mean antibiotic utilization rate (AUR) by 25% in participant NICUs.

RESULT

Aggregate AUR was reduced by 15.3% (p < 0.001). There was a wide range in improvement among participant NICUs. There were no increases in EOS rates or nosocomial infection rates related to the intervention.

CONCLUSION

Participation in this multicenter NICU antibiotic stewardship collaborative targeting EOS was associated with an aggregate reduction in antibiotic use. This study informs efforts aimed at sustaining improvements in NICU AURs.

Umbelliferone modulates the quorum sensing and biofilm of Gram - ve bacteria: in vitro and in silico investigations

In last two decades, the world has seen an exponential increase in the antimicrobial resistance (AMR), making the issue a serious threat to human health. The mortality caused by AMR is one of the leading causes of human death worldwide. Till the end of the twentieth century, a tremendous success in the discovery of new antibiotics was seen, but in last two decades, there is negligible progress in this direction. The increase in AMR combined with slow progress of antibiotic drug discovery has created an urgent demand to search for newer methods of intervention to combat infectious diseases. One of such approach is to look for biofilm and quorum sensing (QS) inhibitors. Plants are excellent source of wide class compounds that can be harnessed to look for the compounds with such properties. This study proves a broad-spectrum biofilm and QS inhibitory potential of umbelliferone. More than 85% reduction in violacein production Chromobacterium violaceum 12472 was found. All tested virulent traits of Pseudomonas aeruginosa PAO1 and Serratia marcescens MTCC 97 were remarkably inhibited that ranged from 56.62% to 86.24%. Umbelliferone also successfully prevented the biofilm of test bacteria at least by 67.68%. Umbelliferone interacted at the active site of many proteins of QS circuit, which led to the mitigation of virulent traits. The stable nature of complexes of umbelliferone with proteins further strengthens in vitro results. After examining the toxicological profile and other drug-like properties, umbelliferone could be potentially developed as new drug to target the infections caused by Gram - ve bacteria.Communicated by Ramaswamy H. Sarma.

The evolution of antimicrobial peptide resistance in Pseudomonas aeruginosa is severely constrained by random peptide mixtures

The prevalence of antibiotic-resistant pathogens has become a major threat to public health, requiring swift initiatives for discovering new strategies to control bacterial infections. Hence, antibiotic stewardship and rapid diagnostics, but also the development, and prudent use, of novel effective antimicrobial agents are paramount. Ideally, these agents should be less likely to select for resistance in pathogens than currently available conventional antimicrobials. The usage of antimicrobial peptides (AMPs), key components of the innate immune response, and combination therapies, have been proposed as strategies to diminish the emergence of resistance. Herein, we investigated whether newly developed random antimicrobial peptide mixtures (RPMs) can significantly reduce the risk of resistance evolution in vitro to that of single sequence AMPs, using the ESKAPE pathogen Pseudomonas aeruginosa (P. aeruginosa) as a model gram-negative bacterium. Infections of this pathogen are difficult to treat due the inherent resistance to many drug classes, enhanced by the capacity to form biofilms. P. aeruginosa was experimentally evolved in the presence of AMPs or RPMs, subsequentially assessing the extent of resistance evolution and cross-resistance/collateral sensitivity between treatments. Furthermore, the fitness costs of resistance on bacterial growth were studied and whole-genome sequencing used to investigate which mutations could be candidates for causing resistant phenotypes. Lastly, changes in the pharmacodynamics of the evolved bacterial strains were examined. Our findings suggest that using RPMs bears a much lower risk of resistance evolution compared to AMPs and mostly prevents cross-resistance development to other treatments, while maintaining (or even improving) drug sensitivity. This strengthens the case for using random cocktails of AMPs in favour of single AMPs, against which resistance evolved in vitro, providing an alternative to classic antibiotics worth pursuing.

Topical or oral antibiotics in childhood acute otitis media and ear discharge: a randomized controlled non-inferiority trial

BACKGROUND

Current guidance suggests oral antibiotics can be considered for children with acute otitis media (AOM) and ear discharge, but there is an absence of evidence regarding the relative effectiveness of antibiotic-corticosteroid eardrops.

AIM

To establish whether antibiotic-corticosteroid eardrops are non-inferior to oral antibiotics in children with AOM and ear discharge.

DESIGN AND SETTING

Open randomized controlled non-inferiority trial set in Dutch primary care.

METHODS

Children were randomized to hydrocortisone-bacitracin-colistin eardrops (five drops, three times per day in the discharging ear(s)) or amoxicillin suspension (50 mg per kilogram of body weight per day, divided over three doses administered orally) for 7 days. The primary outcome was the proportion of children with resolution of ear pain and fever at day 3.

RESULTS

Between December 2017 and March 2023, 58 of the planned 350 children were recruited due to slow accrual for various reasons. Children assigned to eardrops (n = 26) had lower resolution rates of ear pain and fever at 3 days compared to those receiving oral antibiotics (n = 31): 42% vs 65%; adjusted risk difference 20.3%, 95% confidence interval -5.3% to 41.9%), longer parent-reported ear discharge (6 vs 3 days; P = .04), and slightly higher mean ear pain scores (Likert scale 0-6) over days 1-3 (2.1 vs 1.4, P = .02), but received fewer oral antibiotic courses in 3months (11 for 25 children vs 33 for 30 children), and had less GI upset and rash (12% vs 32% and 8% vs 16%, respectively).

CONCLUSION

Early termination stopped us from determining non-inferiority of antibiotic-corticosteroid eardrops. Our limited data, requiring confirmation, suggest that oral antibiotics may be more effective than antibiotic-corticosteroid eardrops in resolving symptoms and shortening the duration of ear discharge.

Risk factors for mortality in culture-negative neonatal sepsis in Malawi: a propensity score-matched analysis

We conducted a propensity score-matched multivariable regression analysis of 1050 culture-negative neonatal sepsis cases in Malawi, where 160 (15.2%) died. Mortality among neonates with culture-negative sepsis was associated with very low birth weight (adjusted OR (AOR) 12.82, 95% CI 1.23 to 137.49), respiratory distress syndrome (AOR 13.20, 95% CI 2.58 to 83.66), a low Apgar score at 1 min (AOR 3.50, 95% CI 1.21 to 10.72) and at 5 min (AOR 4.77, 95% CI 1.94 to 12.50). Addressing maternal and perinatal factors around health and delivery of care is key to improving outcomes in the context of culture-negative sepsis in neonates from low-income country settings like Malawi.

Unveiling the potent activity of a synthetic ion transporter against multidrug-resistant Gram-positive bacteria and biofilms

The increasing prevalence of drug-resistant infections caused by Gram-positive bacteria poses a significant threat to public healthcare. These pathogens exhibit not only smart resistance mechanisms but also form impenetrable biofilms on various surfaces, rendering them resilient to conventional therapies. In this study, we present the potent antibacterial activity of a synthetic ion transporter T against multi-drug resistant (MDR) Gram-positive pathogens, with minimum inhibitory concentration (MIC) values ranging from 0.5 to 2 μg mL-1. The compound demonstrates high selectivity with negligible toxicity towards mammalian cells (HC50 = 810 μg mL-1). It exhibits fast killing kinetics, completely eliminating >5 log bacterial cells within 12 h. Moreover, the compound displays efficacy against both planktonic bacteria and preformed biofilms of methicillin-resistant S. aureus (MRSA), reducing the bacterial burden within the biofilm by 2 log. Mechanistic investigations reveal that the ion transporter depolarizes the bacterial membrane potential and enhances membrane permeability. Additionally, it generates reactive oxygen species, contributing to its bactericidal activity. Notably, MRSA did not exhibit detectable resistance to the ion transporter even after serial passaging for 10 days. Collectively, this novel class of ion transporter holds promise as a therapeutic candidate for combating infections caused by multi-drug resistant Gram-positive bacteria.

Sewage Sludge Promotes the Accumulation of Antibiotic Resistance Genes in Tomato Xylem

Xylem serves as a conduit linking soil to the aboveground plant parts and facilitating the upward movement of microbes into leaves and fruits. Despite this potential, the composition of the xylem microbiome and its associated risks, including antibiotic resistance, are understudied. Here, we cultivated tomatoes and analyzed their xylem sap to assess the microbiome and antibiotic resistance profiles following treatment with sewage sludge. Our findings show that xylem microbes primarily originate from soil, albeit with reduced diversity in comparison to those of their soil microbiomes. Using single-cell Raman spectroscopy coupled with D2O labeling, we detected significantly higher metabolic activity in xylem microbes than in rhizosphere soil, with 87% of xylem microbes active compared to just 36% in the soil. Additionally, xylem was pinpointed as a reservoir for antibiotic resistance genes (ARGs), with their abundance being 2.4-6.9 times higher than in rhizosphere soil. Sludge addition dramatically increased the abundance of ARGs in xylem and also increased their mobility and host pathogenicity. Xylem represents a distinct ecological niche for microbes and is a significant reservoir for ARGs. These results could be used to manage the resistome in crops and improve food safety.

Rapid Membrane-Penetrating Hybrid Peptides Achieve Efficient Dual Antimicrobial and Antibiofilm Activity through a Triple Bactericidal Mechanism

Antimicrobial peptides (AMPs) are a type of biomaterial used against multidrug resistant (MDR) bacteria. This study reports the design of a peptide family rich in tryptophan and lysine obtained by optimizing a natural AMP using single factor modification and pheromone hybridization to expedite the penetration and improve the antimicrobial activity of AMPs. S-4, L-4, and P-4 showed α-helical structures, exhibited extremely fast membrane penetration rates in vitro, and could kill MDR bacteria efficiently within 30 min. Intracellular fluorescence localization suggested rapid membrane-penetrating of AMPs within 1 min, making it more difficult for bacteria to develop resistance. Furthermore, they could effectively inhibit and destroy bacterial biofilms with dual antimicrobial and antibiofilm activity. In the treatment of skin infections caused by MDR-Acinetobacter baumannii in vivo , AMPs could effectively alleviate inflammation without toxic side effects. Additionally, the triple antimicrobial damage of AMPs was described in detail. AMPs rapidly penetrate the cell membrane, inducing cell membrane damage, triggering oxidative damage with a storm of reactive oxygen species and leading to bacterial death through leakage of cellular contents by complexing with DNA. The multiple damage is an important means by which AMPs can prevent bacterial resistance adequately.

Persistence and evidence for accelerated biodegradation of streptomycin in agricultural soils

Some antibiotics are used for the treatment of various bacterial crop diseases, and there is a concern that this practice may represent a selection pressure that increases the reservoir of antibiotic resistance carried by bacteria in crop production systems. Since the 1950s the aminoglycoside antibiotic streptomycin has been widely used for the treatment of some bacterial crop diseases such as fire blight in apples and pears. Following application, the time that bacteria will be exposed to the antibiotic, and therefore the pressure for selection of resistance, will vary according to the environmental persistence of the antibiotic. In the present study, the dissipation of streptomycin was examined in soils supplemented with 5 mg streptomycin/kg soil and incubated for 21 days under laboratory conditions. The impact of two key rate-controlling variables, soil texture (sandy loam, loam, clay loam) and temperature (4, 20, 30 °C) on streptomycin persistence were explored. -Robust methods for streptomycin extraction and analysis by LC-MS/MS were developed. Streptomycin dissipation followed first order kinetics, with the time to dissipate 50 % of the parent compound (DT50) in soils of varying texture incubated at 20 °C ranging from about seven to 15 days. In contrast, the DT50 of streptomycin in autoclaved loam soil incubated at 20 °C was about 111 days. At 4 °C the DT50 ranged from 49 to 137 days. Under no incubation conditions were any extractable transformation products obtained. Streptomycin was dissipated significantly more rapidly in field soil that had a prior history of exposure to the antibiotic than in soil that did not. Taken together, these results indicate that streptomycin is amenable to biodegradation in agricultural soils with DT50s of several days when temperature is permissive.

Tackling Carbapenem Resistance and the Imperative for One Health Strategies-Insights from the Portuguese Perspective

Carbapenemases, a class of enzymes specialized in the hydrolysis of carbapenems, represent a significant threat to global public health. These enzymes are classified into different Ambler's classes based on their active sites, categorized into classes A, D, and B. Among the most prevalent types are IMI/NMC-A, KPC, VIM, IMP, and OXA-48, commonly associated with pathogenic species such as Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The emergence and dissemination of carbapenemase-producing bacteria have raised substantial concerns due to their ability to infect humans and animals (both companion and food-producing) and their presence in environmental reservoirs. Adopting a holistic One Health approach, concerted efforts have been directed toward devising comprehensive strategies to mitigate the impact of antimicrobial resistance dissemination. This entails collaborative interventions, highlighting proactive measures by global organizations like the World Health Organization, the Center for Disease Control and Prevention, and the Food and Agriculture Organization. By synthesizing the evolving landscape of carbapenemase epidemiology in Portugal and tracing the trajectory from initial isolated cases to contemporary reports, this review highlights key factors driving antibiotic resistance, such as antimicrobial use and healthcare practices, and underscores the imperative for sustained vigilance, interdisciplinary collaboration, and innovative interventions to curb the escalating threat posed by antibiotic-resistant pathogens. Finally, it discusses potential alternatives and innovations aimed at tackling carbapenemase-mediated antibiotic resistance, including new therapies, enhanced surveillance, and public awareness campaigns.

Berberine hydrochloride reduces staphyloxanthin synthesis by inhibiting fni genes in methicillin-resistant Staphylococcus aureus

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) poses a great health threat to humans. Looking for compounds that could reduce the resistance of S. aureus towards methicillin is an effective way to alleviate the antimicrobial resistance crisis.

METHODS AND RESULTS

Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), Time-killing growth curve, staphyloxanthin and penicillin-binding protein 2a (PBP2a) were detected. A quantitative polymerase chain reaction was used to measure the effect of BBH on the gene transcription profiles of MRSA. The MIC of MRSA-ST59-t437 towards oxacillin was 8 µg/ml, and MBC was 128 µg/ml. After adding a sub-inhibitory concentration of BBH, the MIC and MBC of MRSA-ST59-t478 towards oxacillin went down to 0.125 and 32 µg/ml respectively. The amount of PBP2a and staphyloxanthin were reduced after treatment with BBH. Moreover, the transcription levels of sarA, mecA and fni genes were downregulated.

CONCLUSIONS

It is for the first time reported that BBH could inhibit staphyloxanthin synthesis by inhibiting fni gene. Moreover, fni might be the target gene of sarA, and there might be another regulatory pathway to inhibit staphyloxanthin biosynthesis. BBH could effectively reduce the methicillin resistance of MRSA-ST59-t437 by downregulating fni, sarA and mecA genes.