Search Results (390)

Antimicrobial resistance (AMR) has emerged as a planetary health emergency, driven not only by the clinical misuse of antibiotics but also by diverse environmental dissemination pathways. This review critically examines the role of environmental compartments—water, soil, and air—as dynamic reservoirs and transmission routes for antibiotic-resistant bacteria (ARB) and resistance genes (ARGs). Recent metagenomic, epidemiological, and mechanistic evidence demonstrates that anthropogenic pressures—including pharmaceutical effluents, agricultural runoff, untreated sewage, and airborne emissions—amplify resistance evolution and interspecies gene transfer via horizontal gene transfer mechanisms, biofilms, and mobile genetic elements. Importantly, it is not only highly polluted rivers such as the Ganges that contribute to the spread of AMR; even low concentrations of antibiotics and their metabolites, formed during or after treatment, can significantly promote the selection and dissemination of resistance. Environmental hotspots such as European agricultural soils and airborne particulate zones near wastewater treatment plants further illustrate the complexity and global scope of pollution-driven AMR. The synergistic roles of co-selective agents, including heavy metals, disinfectants, and microplastics, are highlighted for their impact in exacerbating resistance gene propagation across ecological and geographical boundaries. The efficacy and limitations of current mitigation strategies, including advanced wastewater treatments, thermophilic composting, biosensor-based surveillance, and emerging regulatory frameworks, are evaluated. By integrating a One Health perspective, this review underscores the imperative of including environmental considerations in global AMR containment policies and proposes a multidisciplinary roadmap to mitigate resistance spread across interconnected human, animal, and environmental domains. Full article

Acne vulgaris is a multifactorial inflammatory skin disorder that significantly impairs quality of life and may signal underlying systemic dysfunction, particularly in adult women with treatment-resistant or atypical presentations. This case series presents three clinically and etiologically distinct examples of persistent acne in female patients, each associated with different contributing factors: long-term topical corticosteroid misuse, polycystic ovary syndrome (PCOS), and metabolic syndrome with autoimmune thyroiditis. All cases underwent comprehensive dermatologic evaluation, endocrine/metabolic assessments, and personalized therapeutic interventions, ranging from corticosteroid withdrawal and barrier repair to hormonal modulation and insulin-sensitizing therapy. Clinical progression was monitored for up to six months, revealing favorable responses in all cases, with substantial lesion clearance and improved skin quality. These real-world cases highlight the importance of an integrative, interdisciplinary diagnostic approach in refractory acne and support the need for individualized, long-term management strategies tailored to underlying systemic contributors. Full article

The role of Enterococcus spp. in food is debated since this group of lactic acid bacteria contains opportunistic pathogenic strains, some of which exhibit a multidrug-resistant profile. In livestock farms, the use of antibiotics is the most common practice to deal with mastitis-causing bacteria. However, the heavy usage and/or misuse of antibiotics has led to the emergence of antibiotic resistance. This study aimed to genetically and phenotypically characterize Enterococcus strains isolated from raw sheep milk. Samples were collected over one year from the bulk tank of a dairy sheep farm and cultured on selective media. Isolates were purified and analyzed by whole-genome sequencing and antimicrobial susceptibility testing. The isolates were divided into clusters and the corresponding species were identified along with their genes related to virulence and antibiotic resistance. The pan-, core- and accessory-genomes of the strains were determined. Finally, the antibiotic-resistant profile of selected strains was examined and associated with their genomic characterization. These findings contribute to a better understanding of Enterococci epidemiology, providing comprehensive profiles of their virulence and resistance genes. The presence of antibiotic-resistant bacteria in raw sheep milk destined for the production of cheese should raise awareness. Full article

Vibrio parahaemolyticus is a pathogenic bacterium widely distributed in marine environments, posing significant threats to aquatic organisms and human health. The overuse and misuse of antibiotics has led to the development of multidrug- and pan-resistant V. parahaemolyticus strains. There is an urgent need for novel antibacterial therapies with innovative mechanisms of action. In this work, a genome-scale metabolic network model (GMSN) of V. parahaemolyticus, named VPA2061, was reconstructed to predict the metabolites that can be explored as potential drug targets for eliminating V. parahaemolyticus infections. The model comprises 2061 reactions and 1812 metabolites. Through essential metabolite analysis and pathogen–host association screening with VPA2061, 10 essential metabolites critical for the survival of V. parahaemolyticus were identified, which may serve as key candidates for developing new antimicrobial strategies. Additionally, 39 structural analogs were found for these essential metabolites. The molecular docking analysis of the essential metabolites and structural analogs further investigated the potential value of these metabolites for drug design. The GSMN reconstructed in this work provides a new tool for understanding the pathogenic mechanisms of V. parahaemolyticus. Furthermore, the analysis results regarding the essential metabolites hold profound implications for the development of novel antibacterial therapies for V. parahaemolyticus-related disease. Full article

Background: Antibiotic resistance (AMR) is a critical global and national health challenge, largely driven by the misuse and overuse of antibiotics. Understanding the public′s knowledge and practices regarding antibiotic use is essential for informing effective interventions. This study aimed to assess the levels of knowledge, attitude, and practice (KAP) related to antibiotic use among adults in Saudi Arabia’s Western Region and to identify the demographic and behavioral determinants of these outcomes. Methods: A regional cross-sectional survey was conducted from March to June 2025 using a 40-item self-administered online questionnaire. Adults aged ≥ 18 years residing in the Western Region of Saudi Arabia were recruited via social media using snowball sampling. Descriptive statistics and Chi-square tests were used to examine associations, while multivariate logistic regression was employed to identify determinants of high knowledge and good practices, presented as adjusted odds ratios (aOR) with 95% confidence intervals (CI). Results: A total of 891 participants were included; most were female (63.6%) and aged 18–30 years (56.2%). Moderate knowledge of antibiotic use was observed in 54.0% of participants, while 30.8% had high knowledge. In terms of attitude and practice, 55.6% demonstrated good performance and 42.8% average performance. High knowledge was significantly associated with the female gender (aOR = 1.90; 95% CI: 1.34–2.70), age of 41–50 years (aOR = 2.22; 95% CI: 1.42–3.48), and a postgraduate education (aOR = 15.37; 95% CI: 1.84–128.13). Good practices were associated with the female gender (aOR = 2.32; 95% CI: 1.66–3.24) and being married (aOR = 1.99; 95% CI: 1.43–2.77). A moderate positive correlation was found between knowledge and practice scores (r = 0.406, p < 0.001). Conclusions: Significant variability in public KAP regarding antibiotic use was identified. Female gender, older age, and higher education were key determinants of better KAP. These findings emphasize the need for targeted educational strategies focusing on high-risk groups to support rational antibiotic use and mitigate antimicrobial resistance. Full article

The war between humans and bacteria started centuries ago. With the advent of antibiotics, there was a temporary ceasefire in this war, but the scenario soon started becoming worse with the emergence of drug-resistant strains within years of the deployment of antibiotics in the market. With the surge in the misuse of antibiotics, there was a drastic increase in the number of multidrug-resistant (MDR) and extensively drug-resistant bacterial strains, even to antibiotics like Methicillin and vancomycin, aggravating the healthcare scenario. The threat of MDR ESKAPE pathogens is particularly high in nosocomial infections, where biofilms formed by bacteria create a protective barrier that makes them highly resistant to antibiotics, complicating the treatment efforts. Scientists are looking at natural and sustainable solutions, as several studies have projected deaths contributed by drug-resistant bacteria to go beyond 50 million by 2050. Many plant-derived metabolites have shown excellent antibacterial and antibiofilm properties that can be tapped for combating superbugs. The present review explores the current status of various studies on antibacterial plant metabolites like alkaloids and flavonoids and their mechanisms in disrupting biofilms and killing bacteria by way of inhibiting key survival strategies of bacteria like motility, quorum-sensing, reactive oxygen species production, and adhesion. These mechanisms were found to be varied in Gram-positive, Gram-negative, and acid-fast bacteria like Mycobacterium tuberculosis, which will be discussed in detail. The successful tapping of the benefits of such plant-derived chemicals in combination with evolving techniques of nanotechnology and targeted drug delivery can go a long way in achieving the goal of One Health, which advocates the unity of multiple practices for the optimal health of people, animals, and the environment. Full article

Background/Objective: Non-typhoidal Salmonella is a leading cause of foodborne illness worldwide and presents a significant One Health concern due to zoonotic transmission. Although antibiotic therapy remains a standard approach for treating salmonellosis in severe cases in animals, the widespread misuse of antibiotics has contributed to the emergence of multidrug-resistant (MDR) Salmonella strains. This study provides insights into the genotypic and phenotypic characteristics among Salmonella isolates from necropsied cattle. Methods: A total of 1008 samples were collected from necropsied cattle. Salmonella enterica subspecies were identified by MALDI-TOF MS and subsequently confirmed by serotyping. The biofilm-forming ability of the isolated bacteria was assessed using a crystal violet assay. The motility of the isolates was assessed on soft agar plates. Additionally, the antimicrobial resistance genes (ARGs) and virulence genes were investigated. Antimicrobial resistance patterns were investigated against 19 antibiotics representing 9 different classes. Results:Salmonella species were isolated and identified in 27 necropsied cattle. Salmonella Dublin was the most prevalent serotype (29.6%). Additionally, all the isolates were biofilm producers at different levels of intensity, and 96.3% of the isolates exhibited both swarming and swimming motility. Furthermore, virulence genes, including invA, hilA, fimA, and csgA, were detected in all the isolates. The highest resistance was observed to macrolides (azithromycin and clindamycin) (100%), followed by imipenem (92.6%), and chloramphenicol (85.2%). All isolates were multidrug-resistant, with a multiple antibiotic resistance (MAR) index ranging between 0.32 and 0.74. The aminoglycoside resistance gene aac(6′)-Ib was detected in all the isolates (100%), whereas the distribution of other antimicrobial resistance genes (ARGs) varied among the isolates. Conclusions: The increasing prevalence of MDR Salmonella poses a significant public health risk. These resistant strains can reduce the effectiveness of standard treatments and elevate outbreak risks. Strengthening surveillance and regulating antibiotic use in livestock are essential to mitigating these threats. Full article

Mycoplasma pneumoniae, a cell wall-deficient pathogen, primarily affects children and adolescents, causing Mycoplasma pneumoniae pneumonia (MPP). Following the relaxation of non-pharmaceutical interventions (NPIs) post COVID-19, there has been a global increase in MPP cases and macrolide-resistant strains. Vaccination against M. pneumoniae is being explored as a promising approach to reduce infections, limit antibiotic misuse, and prevent the emergence of drug-resistant variants. We developed an mRNA vaccine, mRNA-SP+P1, incorporating a eukaryotic signal peptide (tissue-type plasminogen activator signal peptide) fused to the C-terminal region of the P1 protein. Targeting amino acids 1288 to 1518 of the P1 protein, the vaccine was administered intramuscularly to BALB/c mice in a three-dose regimen. To evaluate immunogenicity, we quantified anti-P1 IgG antibody titers using enzyme-linked immunosorbent assays (ELISAs) and assessed cellular immune responses by analyzing effector memory T cell populations using flow cytometry. We also tested the functional activity of vaccine-induced sera for their ability to inhibit adhesion of the ATCC M129 strain to KMB17 cells. The vaccine’s protective efficacy was assessed against the ATCC M129 strain and its cross-protection against the ST3-resistant strain. Transcriptomic analysis was conducted to investigate gene expression changes in peripheral blood, aiming to uncover mechanisms of immune modulation. The mRNA-SP+P1 vaccine induces P1 protein-specific IgG antibodies and an effector memory T-cell response in BALB/c mice. Adhesion inhibition assays demonstrated that serum from vaccinated mice attenuatesthe adhesion ability of ATCC M129 to KMB17 cells. Furthermore, three doses of the vaccine confer significant and long-lasting, though partial, protection against the ATCC M129 strain and partial cross-protection against the ST3 drug-resistant strain. Transcriptome analysis revealed significant gene expression changes in peripheral blood, confirming the vaccine’s capacity to elicit an immune response from the molecular level. Our results indicate that the mRNA-SP+P1 vaccine appears to be an effective vaccine candidate against the prevalence of Mycoplasma pneumoniae. Full article

Background/Objectives: Ceftiofur hydrochloride (CEF) is a third-generation cephalosporin widely used in cattle to treat various disease. The recommended dosage was 1.1 to 2.2 mg/kg BW for 3 to 5 consecutive days by intramuscular or subcutaneous injection. Incomplete treatment, overuse, or misuse, often observed in clinical practice, are major contributors to resistance development. This study aims to explore how different concentrations, durations, and dosing frequencies affect susceptibility and bactericidal efficacy of Staphylococcus aureus to optimize CEF dosage regimens. Methods: First, CEF was intermittently administered at 1/2 × minimum inhibitory concentration (MIC), 2 × MIC, 6 × MIC, and 100 × MIC for 30 cycles. Second, CEF was continuously administered for 48, 72, 96, 120, 144, and 168 h. Bacterial susceptibility, regrowth, survival rate, and the emergence of persisters or tolerant phenotypes were assessed. Genetic mutations were identified by whole-genome resequencing. Membrane permeability, integrity, and efflux pump activity were analyzed to elucidate the mechanism of CEF. Results: After 30 cycles, the MIC increased eight-fold in the 2 × MIC group. No significant MIC increase was found in other groups, but a progression from susceptibility to persistence and then to tolerance was observed in the 100 × MIC intermittent group. The survival rate increased both in the 2 × MIC and 100 × MIC groups. With continuous exposure to ≥6 × MIC over 120 h, strains were completely eradicated without MIC increase. Resistance-associated single-nucleotide polymorphism (SNP) mutations were detected only in strains of the 2 × MIC and 100 × MIC intermittent groups. CEF altered the membrane hydrophobicity, damaging membrane integrity after 30 cycles. Conclusions: These findings suggest that high-dose, prolonged exposure is more effective for eliminating Staphylococcus aureus and avoiding resistance, whereas intermittent dosing may promote persistence, tolerance, and resistance evolution. Full article

The intersection of microbial food safety and antimicrobial resistance (AMR) represents a mounting global threat with profound implications for public health, food safety, and sustainable development. This review explores the complex pathways through which foodborne pathogens—such as Salmonella spp., Escherichia coli (E. coli), Listeria monocytogenes (L. monocytogenes), and Campylobacter spp.—acquire and disseminate resistance within human, animal, and environmental ecosystems. Emphasizing a One Health framework, we examine the drivers of AMR across sectors, including the misuse of antibiotics in agriculture, aquaculture, and clinical settings, and assess the role of environmental reservoirs in sustaining and amplifying resistance genes. We further discuss the evolution of surveillance systems, regulatory policies, and antimicrobial stewardship programs (ASPs) designed to mitigate resistance across the food chain. Innovations in next-generation sequencing, metagenomics, and targeted therapeutics such as bacteriophage therapy, antimicrobial peptides (AMPs), and CRISPR-based interventions offer promising alternatives to conventional antibiotics. However, the translation of these advances into practice remains uneven, particularly in low- and middle-income countries (LMICs) facing significant barriers to diagnostic access, laboratory capacity, and equitable treatment availability. Our analysis underscores the urgent need for integrated, cross-sectoral action—anchored in science, policy, and education—to curb the global spread of AMR. Strengthening surveillance, investing in research, promoting responsible antimicrobial use, and fostering global collaboration are essential to preserving the efficacy of existing treatments and ensuring the microbiological safety of food systems worldwide. Full article

Background: Antimicrobial resistance (AMR) poses a critical global health challenge, particularly in resource-limited settings. A hub-and-spoke model, decentralising expertise and distributing resources to peripheral facilities, has been proposed as a strategy to enhance the antimicrobial stewardship (AMS) capacity in low- and middle-income countries. Aim: This study sought to understand healthcare professionals’ experiences of a hub-and-spoke AMS model in the Volta Region of Ghana and its influence on clinical practice, leadership, and collaborative endeavours to address AMR. Methods: A qualitative descriptive design was adopted. In-depth interviews were conducted with 11 healthcare professionals who participated in the AMS program. Thematic analysis was used to identify key themes related to the knowledge and skills that were gained, clinical and leadership practice changes, capacity building, and challenges. Results: Participants reported an increased awareness of AMR, particularly regarding the scale and clinical implications of antimicrobial misuse. The clinical practice improvements included more judicious prescribing and enhanced adherence to infection prevention and control measures. Many respondents highlighted stronger leadership skills and a commitment to capacity building through AMS committees, multidisciplinary collaboration, and cross-organisational knowledge exchange. Despite resource constraints and logistical hurdles, participants expressed optimism, citing data-driven approaches such as point prevalence surveys to track progress and inform policy. Engagement with hospital management and public outreach were viewed as essential to sustaining AMS efforts and curbing over-the-counter antibiotic misuse. Conclusions: The hub-and-spoke model caused observable improvements in AMS knowledge, clinical practice, and leadership capacity among healthcare professionals in Ghana. While challenges remain, particularly in securing sustainable resources and shifting community behaviours, these findings underscore the potential of network-based programs to catalyse systemic changes in tackling AMR. Future research should explore long-term outcomes and strategies for embedding AMS practices more deeply within healthcare systems and communities. Full article

Antimicrobial resistance (AMR) is considered a global healthcare emergency in the 21st century. Although the evolution of microorganisms through Darwinian mechanisms and antibiotic misuse are established drivers, the structural socioeconomic factors of AMR remain insufficiently explored. This review takes on an analytical perspective, drawing upon a wide spectrum of evidence to examine the extent to which socioeconomic factors contribute to the global proliferation of AMR, with an emphasis on low- and middle-income countries (LMICs). The analytical review at hand was carried out through a search for relevant articles and reviews on PubMed, Google Scholar, the Centers for Disease Control and Prevention, and the World Health Organization database using combinations of the keywords “antimicrobial resistance,” “socioeconomic factors,” “low- and middle-income countries,” “surveillance,” “healthcare access,” and “agriculture.” Preference was given to systematic reviews, high-impact primary studies, and policy documents published in peer-reviewed journals or by reputable global health organizations. Our analysis identifies a complex interplay of systemic vulnerabilities that accelerate AMR in resource-limited settings. A lack of regulatory frameworks regarding non-prescription antibiotic use enables the proliferation of multi-drug-resistant microorganisms. Low sewer connectivity facilitates the environmental dissemination of resistance genes. Proper antibiotic selection is hindered by subpar healthcare systems and limited diagnostic capabilities to deliver appropriate treatment. Additionally, gender disparities, forced migration, and climate-driven zoonotic transmission compound the burden. During the COVID-19 pandemic, antimicrobial misuse surged, further amplifying resistance trends. AMR is not solely a biological phenomenon, but a manifestation of global inequity. Mitigation requires a transformation of policy directed toward a “One Health” strategy that incorporates socioeconomic, environmental, and health system reforms. Strengthening surveillance, investing in infrastructure, regulating pharmaceutical practices, and promoting health equity are essential to curb the rising tide of resistance. Full article

Background: The misuse of antibiotics in dental practice significantly contributes to the escalation of antimicrobial resistance. This study aimed to assess the knowledge and attitudes of final-year dental students regarding perioperative antibiotic prophylaxis in oral surgery and to identify potential curricular improvements based on the findings. Methods: A questionnaire was administered to 117 final-year students at Gazi University Faculty of Dentistry in December 2024. The survey presented clinical scenarios related to common oral surgical procedures, evaluating participants’ antibiotic prescribing behaviors. Statistical analyses were performed using descriptive statistics and a One-Sample Chi-Square Test. Results: Students demonstrated a general tendency toward rational antibiotic use in routine clinical scenarios, with statistically significant response patterns favoring the avoidance of unnecessary prescriptions (p < 0.05). However, in complex or borderline cases such as impacted third molar extraction and dental implant placement, response variability was observed. Post hoc analyses revealed no statistically significant differences between closely distributed options, indicating inconsistencies in decision-making in more challenging scenarios. Conclusions: While final-year dental students exhibited a satisfactory level of knowledge regarding appropriate antibiotic use in standard surgical procedures, the variability observed in complex cases underscores the necessity for enhanced educational interventions. Incorporating updated, evidence-based antimicrobial stewardship principles and promoting clinical decision-making through case-based learning are essential to prepare future dental practitioners for responsible antibiotic prescribing, contributing to global efforts to mitigate antimicrobial resistance. Full article

Background/Objectives: Antibiotic resistance or antimicrobial resistance (AMR) in livestock is a growing global concern that threatens both human and animal health. The overuse and misuse of antibiotics in livestock production have led to an increased propensity for the development of AMR bacterial strains in animals, which can be spread to humans through the consumption of contaminated animal products, direct contact, or environmental exposure. This review aims to summarize the development and transmission of AMR in livestock, explore its underlying mechanisms and impact on human and animal health, and discuss current practices and potential strategies for mitigation and prevention. Methods: For this narrative review, we searched articles on PubMed and Google Scholar using the terms antibiotic resistance, livestock, and environment, alone or in combination. Results: The history of antibiotic use in livestock and its link to increased AMR, along with the involved mechanisms, including the enzymatic breakdown of antibiotics, alterations in bacterial targets, horizontal gene transfer, and efflux pumps, are important. Antibiotics in livestock are used for growth promotion, disease prevention and control, and metaphylactic use. The role of livestock and the environment as reservoirs for resistant pathogens, their impact on human health, chronic infections, allergic reactions, toxicity, and the development of untreatable diseases is important to understand AMR. Conclusions: Given the widespread use of antibiotics and the potential consequences of AMR, collaborative global efforts, increased public awareness, coordinated regulations, and advancements in biological technology are required to mitigate the threat AMR poses to human and animal health. Regulatory solutions and the development of new therapeutic alternatives like antimicrobial peptides and bacteriophage therapy, and preventive measures such as DNA and mRNA vaccines, are future perspectives. Full article

The broiler industry is the most developed livestock sector in Cameroon. This study aimed to evaluate the relationship between biosecurity implementation with production performance and antibiotic usage in broiler farms in Cameroon. Data concerning biosecurity, production performance (average daily gain or ADG, mortality rate, feed conversion ratio or FCR, and performance index or PI), and antimicrobial usage (AMU) were collected in 57 farms in the Adamawa and North regions. The average total biosecurity score of broiler farms was 52/100. ADG (46.54 ± 5.18 g versus 43.80 ± 4.16 g), FCR (1.59 ± 0.61 versus 1.75 ± 0.58), mortality rate (2.47% versus 6.65%), and PI (339.21 ± 105.79 versus 268.22 ± 101.09) were statistically better in farms with good biosecurity. The majority of antibiotics used (55.2%) were classified as critically important for human medicine, with 83.9% of antibiotics underdosed/overdosed. No correlation was found between biosecurity and AMU, although there was a trend towards reduced use in farms with good biosecurity. The misuse of antibiotics will result in an increased development of antimicrobial resistance, which can be transmitted to humans. This study highlights the importance of biosecurity in improving poultry performance and reducing AMU. Continuous training and awareness-raising efforts among farmers on the importance of biosecurity are needed to reduce AMU and improve farmers’ profitability. Full article