Staphylococcus aureus is a formidable human pathogen responsible for infections ranging from superficial skin lesions to life-threatening systemic diseases. This review synthesizes current knowledge on its pathogenesis, emphasizing colonization dynamics, virulence mechanisms, biofilm formation, and antibiotic resistance. By analyzing studies from PubMed, Scopus, and Web of Science, we highlight the pathogen’s adaptability, driven by surface adhesins (e.g., ClfB, SasG), secreted toxins (e.g., PVL, TSST-1), and metabolic flexibility in iron acquisition and amino acid utilization. Nasal, skin, and oropharyngeal colonization are reservoirs for invasive infections, with biofilm persistence and horizontal gene transfer exacerbating antimicrobial resistance, particularly in methicillin-resistant S. aureus (MRSA). The review underscores the clinical challenges of multidrug-resistant strains, including vancomycin resistance and decolonization strategies’ failure to target single anatomical sites. Key discussions address host–microbiome interactions, immune evasion tactics, and the limitations of current therapies. Future directions advocate for novel anti-virulence therapies, multi-epitope vaccines, and AI-driven diagnostics to combat evolving resistance. Strengthening global surveillance and interdisciplinary collaboration is critical to mitigating the public health burden of S. aureus.

Biofilms, structured microbial consortia embedded in self-produced extracellular matrices, pose significant challenges across the medical, industrial, and environmental sectors due to their resistance to antimicrobial therapies and ability to evade the immune system. Their resilience is driven by multifaceted mechanisms, including matrix-mediated drug sequestration, metabolic dormancy, and quorum sensing (QS)-regulated virulence, which collectively sustain persistent infections and contribute to the amplification of antimicrobial resistance (AMR). This review critically examines the potential of plant-derived essential oils (EOs) as innovative agents for biofilm control. EOs exhibit broad-spectrum antibiofilm activity through multi-target mechanisms, including disrupting initial microbial adhesion, degrading extracellular polymeric substances (EPSs), suppressing QS pathways, and compromising membrane integrity. Their ability to act synergistically with conventional antimicrobials at sub-inhibitory concentrations enhances therapeutic efficacy while reducing the selection pressure for resistance. Despite their potential, EO applications face technical challenges, such as compositional variability due to botanical sources, formulation stability issues, and difficulties in standardization for large-scale production. Clinical translation is further complicated by biofilm stage- and strain-dependent efficacy, insufficient in vivo validation of therapeutic outcomes, and potential cytotoxicity at higher doses. These limitations underscore the need for optimized delivery systems, such as nanoencapsulation, to enhance bioavailability and mitigate adverse effects. Future strategies should include combinatorial approaches with antibiotics or EPS-degrading enzymes, advanced formulation technologies, and standardized protocols to bridge laboratory findings to clinical practice. By addressing these challenges, EOs hold transformative potential to mitigate biofilm-associated AMR, offering sustainable, multi-target alternatives for infection management and biofilm prevention in diverse contexts.

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.

Water systems serve as multifaceted environmental pools for antibiotic-resistant bacteria (ARB) and resistance genes (ARGs), influencing human, animal, and ecosystem health. This review synthesizes current understanding of how antibiotics, ARB, and ARGs enter surface, ground, and drinking waters via wastewater discharge, agricultural runoff, hospital effluents, and urban stormwater. We highlight key mechanisms of biofilm formation, horizontal gene transfer, and co-selection by chemical stressors that facilitate persistence and spread. Case studies illustrate widespread detection of clinically meaningful ARB (e.g., Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and mobile ARGs (e.g., sul1/2, tet, bla variants) in treated effluents, recycled water, and irrigation return flows. The interplay between treatment inefficiencies and environmental processes underscores the need for advanced treatment technologies, integrated monitoring, and policy interventions. Addressing these challenges is critical to curbing the environmental dissemination of resistance and protecting human and ecosystem health.

Pseudomonas aeruginosa poses significant health threats due to its multidrug-resistant profile, particularly affecting immunocompromised individuals. The pathogen’s ability to produce virulence factors and antibiotic-resistant biofilms, orchestrated through quorum-sensing (QS) mechanisms, complicates conventional therapeutic interventions. This review aims to critically assess the potential of anti-QS strategies as alternatives to antibiotics against P. aeruginosa infections. Comprehensive literature searches were conducted using databases such as PubMed, Scopus, and Web of Science, focusing on studies addressing QS inhibition strategies published recently. Anti-QS strategies significantly attenuate bacterial virulence by disrupting QS-regulated genes involved in biofilm formation, motility, toxin secretion, and immune evasion. These interventions reduce the selective pressure for resistance and enhance antibiotic efficacy when used in combination therapies. Despite promising outcomes, practical application faces challenges, including specificity of inhibitors, pharmacokinetic limitations, potential cytotoxicity, and bacterial adaptability leading to resistance. Future perspectives should focus on multi-target QS inhibitors, advanced delivery systems, rigorous preclinical validations, and clinical translation frameworks. Addressing current limitations through multidisciplinary research can lead to clinically viable QS-targeted therapies, offering sustainable alternatives to traditional antibiotics and effectively managing antibiotic resistance.

Bovine mastitis, particularly that caused by Staphylococcus aureus, presents a major challenge to dairy production worldwide due to its economic impact, animal welfare concerns, and zoonotic potential. This narrative review synthesizes current literature on the epidemiology, pathogenesis, resistance patterns, and control strategies related to S. aureus-associated mastitis in dairy cattle. It highlights the pathogen’s virulence mechanisms, such as biofilm formation, immune evasion, and toxin production, that facilitate persistent infections. The review compiles global prevalence data, revealing significant geographic variation and disparities between clinical and subclinical cases. Antimicrobial resistance, especially the emergence of methicillin-resistant S. aureus (MRSA), is extensively examined alongside resistance gene profiles. Diagnostic approaches, including culture, PCR, MALDI-TOF MS, and AI-based systems, are evaluated for their sensitivity and field applicability. Additionally, the review addresses public health implications, zoonotic risks, and One Health perspectives, culminating in an exploration of prevention strategies, including improved hygiene, vaccination, dry cow therapy, and AI-driven herd management. The findings emphasize the urgent need for integrated surveillance, precision diagnostics, and targeted interventions to mitigate the burden of S. aureus mastitis.