Search Results (2,319)

Sporothrix species are thermally dimorphic fungi responsible for sporotrichosis, a globally prevalent subcutaneous mycosis and an emerging zoonotic threat, particularly in South America. The high virulence of Sporothrix brasiliensis and its efficient transmission from cats to humans have intensified recent outbreaks, underscoring the importance of understanding the pathogenic mechanisms. While several putative virulence factors have been identified, such as melanin production, cell wall remodeling, extracellular vesicles, and thermotolerance, functional studies remain hampered by limited molecular tools. Recent advances, including random mutagenesis, protoplast-mediated transformation, Agrobacterium tumefaciens-mediated transformation, RNA interference and CRISPR/Cas9-based genome editing, are changing this landscape. These methods have enabled the functional validation of key virulence factors and the investigation of gene function in both environmental and clinical strains. In this review, we summarize the genetic toolbox available for Sporothrix, outline current challenges, and discuss how these strategies are reshaping the study of fungal virulence and host–pathogen interactions. Full article

An investigation on a discrete-time infectious disease model that incorporating vertical transmission is presented in this paper. Departing from prior research centered on continuous-time frameworks, our study adopts a discrete-time formulation to better capture the complex epidemiological dynamics. We establish a model and conduct a bifurcation analysis of its equilibrium points. In particular, sufficient conditions for the local stability and the emergence of Neimark–Sacker and flip bifurcations are rigorously derived and analytically verified. As anticipated, variations in the bifurcation parameter give rise to distinct periodic regimes in the system response. To mitigate the instabilities and chaotic behaviors resulting from these bifurcations, we propose and validate two control strategies, which are Hybrid Control Method and State Feedback Control. Numerical simulations futher substantiated the analytical results, demonstrating that appropriate parameter adjustments can shift the system behavior from chaotic attractors and limit cycles toward stable equilibria. Our results show that by dynamically adjusting the intensity of prevention and control measures to mitigate unstable factors such as vertical transmission and high infection rates, or reducing the frequency of system updates to slow down the growth of infections, the epidemic can be transitioned from repeated outbreaks to a stable and manageable state. Full article

Plant disease specimens are invaluable resources for investigating the origin and spread mechanisms of plant pathogenic microorganisms. Citrus canker, caused by Xanthomonas citri pv. citri (Xcc), is one of the most devastating bacterial diseases in citrus production. Here, we report the complete genome sequence of Xcc strain GD82, isolated from Guangdong Province during the early outbreak stage in the 1980s. Comparative analysis with modern genomes revealed key differences in structural variations, functional single-nucleotide polymorphisms (SNPs), and phage-related fragments, suggesting potential associations between insertions/deletions (InDels) and pathogenicity or environmental adaptation. This study provides critical insights into the evolutionary trajectory of Xcc and the epidemiological dynamics of citrus canker in China. Full article

Norovirus (NoV) and sapovirus (SaV) are major viral pathogens causing acute gastroenteritis (AGE) in both children and adults in developed countries and are also responsible for large-scale outbreaks. However, in Quebec, Canada, there are limited and updated data with respect to the genotypes circulating and implicated in outbreaks, particularly for SaV. This study aimed to investigate the genetic diversity and genotype predominance of NoVs and SaVs associated with AGE outbreaks in Quebec, Canada. Confirmed NoV and SaV outbreaks from long-term care facilities and hospital settings between September 2011 and April 2016 were investigated (n = 252). NoVs and SaVs were genetically diverse: 21 RdRp-capsid combinations were identified, of which 10 are recombinants. NoV GII.4 New Orleans[P4 NewOrleans] was the predominant genotype from 2011 to 2013, and GII.4 Sydney[P31] was the predominant genotype from 2013 to 2015. In 2015–2016, no single genotype predominated; instead, GII.17[P17], GII.4 Sydney[P16], GII.4 Sydney[P31], and SaV GI.2 strains were co-circulating at similar frequencies. Notably, emerging global genotypes including GII.17[P17], GII.4 Sydney[P16], GII.2[P16], and GII.4 San Francisco[P31] were detected for the first time in Quebec. These findings may contribute to an enhanced understanding of NoV and SaV infection and spread, and to the development of candidate vaccines. Full article

In light of the current advances in computational epidemics and the need for improved epidemic governance strategies, we propose a novel meta-agent-based model (meta-ABM) constructed using the global airline complex network, using data from openflights.org, to establish a configurable framework for monitoring epidemic dynamics. By integrating our validated SICARQD complex epidemic model with global flights and airport information, we simulate the progression of an airborne epidemic, specifically reproducing the resurgence of COVID-19. In terms of originality, our meta-ABM considers each airport node (i.e., city) as an individual agent-based model assigned to its own independent SICARQD epidemic model. Agents within each airport node engage in probabilistic travel along established flight routes, mirroring real-world mobility patterns. This paper focuses primarily on investigating the effect of mobility restrictions by measuring the total number of cases, the peak infected ratio, and mortality caused by an epidemic outbreak. We analyze the impact of four key restriction policies imposed on the airline network, as follows: no restrictions, reducing flight frequencies, limiting flight distances, and a hybrid policy. Through simulations on scaled population systems of up to 1.36 million agents, our findings indicate that reducing the number of flights leads to a faster and earlier decrease in total infection cases, while restricting maximum flight distances results in a slower and much later decrease, effective only after canceling over 80% of flights. Notably, for practical travel restriction policies (e.g., 25–75% of flights canceled), epidemic control is significantly more effective when limiting flight frequency. This study shows the critical role of reducing global flight frequency as a public health policy to control epidemic spreading in our highly interconnected world. Full article

Salmonella is a globally prevalent and diverse group of pathogenic bacteria that reside in food animals, such as swine. They possess transmissible antimicrobial resistance (AMR) and virulence factors, causing outbreaks with varying disease outcomes. This study identified and characterized 110 Salmonella enterica isolates from swine meat in abattoirs and wet markets of Metro Manila, Philippines. Thirteen different S. enterica serovars were identified using the Check & Trace microarray platform. The most prevalent were Rissen, Typhimurium 1, 4, [5], 12:i:-, Anatum, and Derby. This study is also the first to report serovar Soerenga in the Philippines and Asia. A high prevalence of virulence genes was observed, namely, hilA (75.45%), avrA (73.64%), mgtC (72.73%), pipB (66.36%), sseC (58.18%), and spi4R (53.64%), with no plasmid-borne spvC and spvR. A high prevalence of bla_TEM (44.55%) was also observed, consistent with the phenotypic AMR profiles. Additionally, 14.81% of the isolates exhibited multidrug resistance. Statistical associations and predictions were also found among virulence genes, serovars, and location types, which highlight implications of Salmonella contamination and serovar variations. These findings suggest the need for continuous surveillance of Salmonella, especially for emerging or rare serovars, the deeper investigation of virulence and AMR mechanisms, and improved regulation and sanitation throughout food animal industries. Full article

Monkeypox (MPOX) is an emerging zoonotic disease caused by monkeypox virus (MPXV), an orthopoxvirus closely related to smallpox. Initially confined to endemic regions in Central and West Africa, MPOX has recently gained global significance with outbreaks reported across multiple continents. MPXV is maintained in animal reservoirs but is increasingly transmitted from person to person, facilitated by close contact, respiratory droplets, and, in some cases, sexual transmission. Clinically, MPOX presents with fever, lymphadenopathy, and a characteristic vesiculopustular rash, though atypical manifestations have been observed in recent outbreaks, complicating diagnosis. Laboratory confirmation relies on molecular testing, while differential diagnosis must consider varicella, herpes, and other vesicular illnesses. Therapeutic options remain limited; supportive care is the cornerstone of management, but antivirals such as tecovirimat and brincidofovir, as well as smallpox vaccines, have shown efficacy in mitigating disease severity and preventing infection. The unprecedented global outbreak has underscored the importance of surveillance, rapid diagnostics, and coordinated public health responses to contain transmission. This review provides an overview of epidemiology, virology, clinical manifestations, modes of transmission, available diagnostics, and prophylactic and therapeutic strategies against MPOX. We also discuss the role of animal reservoirs, viral evolution, and human-to-human transmission in shaping the dynamics of recent MPOX outbreaks. By summarizing the latest evidence, this review aims to inform clinicians, researchers, and policymakers about key aspects of MPOX biology, clinical management, and prevention, while identifying gaps that warrant future investigation for the control of this and potentially other emerging zoonotic-related pathogens with an impact on human health. Full article

Background: West Nile Virus (WNV) is a mosquito-borne flavivirus responsible for seasonal outbreaks in temperate and tropical regions, including Europe, the Mediterranean, and the Middle East. Its transmission via mosquitoes, particularly Culex species, poses persistent challenges to public health. Despite ongoing efforts, comprehensive prevention and treatment strategies remain limited. Methods: A comprehensive search of peer-reviewed literature, clinical trials, and government surveillance data from Italy and Iran was conducted using PubMed, Scopus, Web of Science, and supplementary web-based resources. Inclusion criteria focused on molecular studies of WNV, vaccine and antiviral drug development, and regional outbreak reports. Results: WNV transmission is influenced by climatic conditions, as well as vector distribution and ecological patterns. While human vaccines are currently under development, only veterinary vaccines yielded promising but still limited evidence of effectiveness. Notably, therapeutic measures are currently limited to supportive care, whereas investigational antiviral drugs are in early-stage trials. Interestingly, Italy demonstrates robust surveillance with regular reporting of outbreaks, whereas data from Iran indicate that despite a widespread serological footprint, especially in southern and southwestern provinces, the reported clinical impact on humans and animals appears comparatively less severe. Conclusions: Bridging gaps in vaccine availability, therapeutic innovation, and disease monitoring is essential for effective WNV management to prepare for potential severe future outbreaks in Europe and the Middle East. On the other hand, regional differences between Italy and Iran reveal the need not only for tailored public health interventions and enhanced surveillance, but also for sustained investment in research. In our view, collaborative frameworks across Mediterranean and Middle Eastern countries in a “One Health” approach may improve preparedness and response to future WNV outbreaks. Full article

In the review, the collection of population genetics papers from 1973 to 2025 comprises 400 publications, 81 of which were significant and consulted with representatives from water and sewage companies. Reviewed Proteobacteria (mean H_S = 0.42), Firmicutes (mean H_S = 0.43), Actinobacteria (mean H_S = 0.33), and Spirochaetes (mean H_S = 0.54) represent the 60 species under investigation through the lens of “h” coefficients related to gene diversity and expected heterozygosity. The research also included ESKAPE, emerging pathogens, bacterial indicators of wastewater treatment efficiency, environmental sanitary surveillance and public health. The restoration of the expected heterozygosity for haploids “h” was proposed in wastewater-based epidemiology as an innovative tool for public health. The unique “h” coefficient allows for the comparison of genetic variability in various organisms, regardless of their ploidy, using multiple markers and traits. The parameter represents a noble character for both the variability of phenotypes (proteins) and genotypes (nucleic acids). Leveraging the genetic diversity highlighted by the “h” coefficient can support wastewater-based epidemiology, offering the ability to predict the stages and trajectories of disease outbreaks. Full article

Background: Cholera, caused by Vibrio cholerae, remains endemic in many developing countries, including Pakistan. The extensive use of antibiotics has led to the emergence of antimicrobial resistance in V. cholerae, limiting available treatment options. In this study, we performed molecular characterisation of antibiotic-resistant V. cholerae serotype Ogawa isolates from a recent cholera outbreak in Khyber Pakhtunkhwa, Pakistan. Methodology: Suspected cholera stool samples were collected from hospitalised patients at various district hospitals of Khyber Pakhtunkhwa Province (KPK), Pakistan. The samples were transported to the Public Health Reference Microbiology Laboratory at Khyber Medical University, Peshawar. V. cholerae were identified based on colonial morphology, Gram staining, and biochemical tests using EPI 10E. For serotype identification, monovalent antisera were used. Antibiotic susceptibility testing (AST) was performed using CLSI M45 and EUCAST guidelines. DNA was extracted from pure colonies of multidrug-resistant (MDR) V. cholerae and subjected to whole-genome sequencing (WGS) for genomic characterisation using an Illumina MiSeq platform. Results: Of the 350 active diarrheal cases investigated, 70 were confirmed as V. cholerae. The outbreak was initially reported in Dir and was subsequently followed by a high incidence of cholera in the Peshawar district of KPK. All strains belong to the Ogawa serotype, which shows high antibiotic resistance, particularly to ampicillin (n = 62, 88.57%), Sulfamethoxazole/Trimethoprim (n = 60, 85.71%), Erythromycin (n = 59, 84.29%), and Tetracycline (n = 53, 75.71%). The lowest resistance was against Meropenem (n = 1, 1.4%), followed by amikacin (n = 7, 10.0%) and levofloxacin (n = 13, 18.57%). Furthermore, 34 (48.57%) of the isolates were MDR, while 13 (18.57%) were extensively drug-resistant. Six samples were selected for whole-genome sequencing. The selection of six V. cholerae samples for WGS was based on their drug resistance pattern and origin of isolation. At the genomic level, all sequenced V. cholerae strains harboured multiple antimicrobial resistance determinants. Quinolone resistance was associated with mutations and genes in gyrA, gyrB, parC, and parE; resistance to sulfamethoxazole–trimethoprim with folA, folP, and dfr; tetracycline resistance with tetA and tet35; chloramphenicol resistance with catB and S10p; and aminoglycoside resistance with hns, S12p, and gigB. In addition, β-lactam resistance was linked to the presence of efflux and β-lactamase genes, including blaSHV and mox-3. Mutations were identified in gyrA at positions S83I, S177A, and S202A, and in parC at positions S85L and I231V. Collectively, the presence of these resistance determinants likely enables V. cholerae to survive exposure to high concentrations of multiple antibiotics. Conclusions: Our V. cholerae isolates showed close genetic relatedness to previously sequenced strains from Pakistan (2010 and 2022), as well as to recently reported international strains from the USA, Australia, and China. These findings highlight both the long-term persistence of these lineages within Pakistan and their international dissemination, likely facilitated by globalisation. Full article

In recent years, China has made strong national commitments to waste reduction and circular economy, including the implementation of mandatory municipal solid waste separation policies and the rollout of zero-waste city initiatives. These efforts represent a strategic shift toward systemic environmental governance. However, the outbreak of the COVID-19 pandemic in early 2020—and the subsequent implementation of the country’s stringent zero-COVID policy—led to an abrupt disruption of these programs. Under this policy, strict lockdowns, quarantine of both confirmed and suspected cases, and city-wide containment became top priorities, sidelining environmental initiatives such as waste separation and sustainable waste infrastructure development. This study investigates how Chinese residents’ motivations for waste separation evolved across three key phases: pre-pandemic, during the zero-COVID enforcement period, and post-pandemic recovery. Grounded in the Theory of Planned Behavior and pro-environmental behavior theory, we developed an extended model incorporating pandemic-related social, psychological, and policy variables. Based on 526 valid questionnaire responses collected in late 2023 in Shanghai, we conducted structural equation modeling and repeated-measures analysis. Findings reveal a significant shift from externally driven compliance—reliant on governmental enforcement and service provision—to internally motivated behavior based on environmental values and personal efficacy. This transition was most evident after the pandemic, suggesting the potential for sustained pro-environmental habits despite weakened policy enforcement. Our findings underscore the importance of strengthening internal drivers in environmental governance, especially under conditions where policy continuity is vulnerable to systemic shocks such as public health emergencies. Full article

Listeria monocytogenes is a foodborne pathogen of significant concern. While it typically causes mild, self-limiting gastroenteritis, it poses a much higher threat to immunocompromised individuals and pregnant women, where it may lead to miscarriage. Numerous outbreaks have been linked to ready-to-eat foods. Although heat treatment is commonly used for microbial decontamination, it is unsuitable for fresh produce such as fruits and vegetables. Other physical (e.g., UV, gamma irradiation) and chemical (e.g., NaOCl, ozone) methods can compromise sensory qualities or face limited consumer acceptance. Photodynamic Inactivation (PDI) has emerged as a promising alternative, particularly when using natural photosensitizers. Because PDI efficacy depends on photosensitizer diffusion, there is a need to further explore how different and complex fruit surface structures may influence its performance. Three fruit models were therefore selected to represent distinct surface textures and were evaluated in situ: apples (smooth), strawberries (irregular), and kiwis (fuzzy and hairy surface). The influence of contamination order was also evaluated, as this factor is highly relevant to real-world supply-chain scenarios but has been largely overlooked in prior research. Additionally, the study investigated how the order of contamination affected the decontamination outcome. Sodium-magnesium-chlorophyllin (Na-Mg-Chl), an approved food additive (E140), was used as photosensitizer. Fruits were cut into 1 cm² squares and inoculated with L. monocytogenes. A 100 µM Na-Mg-Chl solution was applied either before or after bacterial inoculation. All samples were then illuminated using a 395 nm LED (radiant exposure 15 J/cm²). When L. monocytogenes was applied first, followed by the addition of Na-Mg-Chl, a 5.96 log reduction was observed in apples, a 5.71 log reduction in strawberries, and a 6.02 log reduction in kiwis. Conversely, when Na-Mg-Chl was applied prior to bacterial deposition, apples showed a 5.61 log reduction, strawberries demonstrated a 6.34 log reduction, and kiwis achieved the highest inactivation, at 6.74 log units. These results indicate that PDI consistently achieved substantial bacterial reductions across all fruit types, regardless of surface characteristics or application order. This supports PDI as a powerful method for fruit surface decontamination, reducing public health risks and economic losses while preserving product quality and consumer confidence. Full article

This study investigated the molecular and microbial factors behind the higher disease resistance of hybrid taimen by combining gut microbiome profiling with host transcriptomic analysis of intestinal and liver tissues. Both hybrid taimen and H. taimen were raised under the same recirculating aquaculture system (RAS) conditions. After recording survival rates following three enteritis outbreaks, samples of intestinal contents and tissues were collected from both groups. The gut microbiota was analyzed using full-length 16S rRNA sequencing in PacBio, and host gene expression was assessed with Illumina RNA-seq. Functional predictions were made using PICRUSt2 and Gene Set Enrichment Analysis (GSEA). Results showed that hybrids had significantly higher survival rates after enteritis (p < 0.05). Although microbial alpha diversity was similar, beta diversity revealed slight compositional differences. Hybrids showed higher levels of Hapalosiphon and Tepidimicrobium, microbes associated with antimicrobial compounds and the metabolism of short-chain fatty acids (SCFAs). Functional predictions indicated enrichment in selenocompound metabolism and ansamycin biosynthesis in hybrids. Transcriptomic analysis identified 4233 differentially expressed genes (DEGs) in the intestine and 3980 in the liver. In hybrids, intestinal tissues exhibited increased expression of immune pathways, including complement activation, lysosomal activity, and the transforming growth factor-beta (TGF-β) signaling pathway. Liver tissues demonstrated higher expression of genes related to cholesterol synthesis, fatty acid degradation, and the peroxisome proliferator-activated receptor (PPAR) signaling pathway. qRT-PCR validated the expression patterns of 20 selected DEGs. These findings tentatively suggest that the elevated disease resistance of hybrid taimen may be linked, at least in part, to a combination of microbial taxa inferred to produce antimicrobial metabolites and short-chain fatty acids, as well as an apparent intensification of intestinal immune and barrier-related gene expression, and hepatic pathways that possibly support energy supply and steroid-based immunity. However, this multi-omics data set is only correlational. We still do not know whether a single strain or a few host genes are enough to produce the resistant phenotype. Gnotobiotic trials, microbiota transplants, and targeted metabolomics will be necessary to turn these interesting associations into solid evidence. Full article

From August to November 2023, a disease outbreak occurred in a research colony of 33 mixed-sex, five-month-old central bearded dragons obtained from a private breeder in the USA. Clinical presentation consisted primarily of dehydration, lethargy, inappetence, weight loss, neck extension, sporadic open mouth breathing indicating dyspnea, and sudden death. A total of six deaths occurred during this period. Pathological investigation followed by molecular diagnostics and whole-genome sequencing revealed Mycoplasma pogonae as the cause of disease. Pneumonia (5/6) was diagnosed from necropsy. Types of pneumonia included histiocytic (1/5), combined histiocytic and lymphocytic (2/5), histiocytic and granulocytic (1/5), and heterophilic pneumonia (1/5). Our results confirmed that M. pogonae infection is associated with sudden mortality in a colony of captive central bearded dragons in the USA and that M. pogonae has a potential pathogenic role as a primary infectious agent. Full article

The 2025 Ebola outbreak that ravaged the Bulape Health District (HD) in Kasai, Democratic Republic of Congo (DRC), was tackled using the incident management system (IMS) model. The Bulape HD is located in the Mweka territory, which has experienced two Ebola epidemics: one in 2007 and another in 2008. The IMS comprises seven strategies recommended for an effective response to an Ebola outbreak: (i) thorough investigation, (ii) strengthening infection prevention and control measures in the community, (iii) ensuring that medical care is provided by experienced professionals, (iv) strengthening risk communication and community engagement (RCCE), (v) ring vaccination, (vi) operational research, and (vii) anchoring interventions in the existing health system. We share our experience implementing these seven strategies and compare them with those utilized during three previous Ebola outbreaks. This paper describes our achievements, the resulting benefits, and the factors that facilitated the implementation of the aforementioned strategies. A literature review and interviews were conducted. The atlas.ti 22 software was used for data analysis. Implementing these seven strategies contributed to an effective response, largely due to the experience and expertise of those involved but also thanks to the support of technical and financial partners (TFPs) and the engagement of the local community. Challenges such as geographical accessibility, the fragile health system, the community’s strong attachment to traditional practices, and negative reactions to healthcare—which was widely discredited, with many of those involved expressing a lack of faith in its effectiveness—were major obstacles. To overcome these challenges, an integrated approach was utilized, combining a rapid comprehensive response with deep and respectful community engagement. The support and alignment of TFPs were invaluable during this process. The RCCE pillar proved key to successful IMS implementation. Our experiences will be useful during the next Ebola outbreak in the DRC; additionally, they may also help to inform the response to similar outbreaks in other countries. Full article