Search Results (5,180)

Human non-polio enteroviruses (NPEVs) cause a plethora of infections in humans, ranging from mild to severe neurological diseases including aseptic meningitis. NPEVs are the leading cause of aseptic meningitis in both children and adults worldwide. In Russia, reports of NPEV infections have surged, especially in the post-COVID era starting in 2022, with elevated infection rates into 2023. A comprehensive examination of the whole genome is crucial for understanding the evolution of NPEV genes and for predicting potential outbreaks. This study focused on identifying the circulating NPEV strains in the Ural Federal District and Western Siberia, using Sanger sequencing and next-generation sequencing (NGS) methodologies. Biological samples were collected from (n = 225) patients diagnosed with aseptic meningitis. Bioinformatics analysis targeted the nucleotide sequences of the major capsid protein (partial VP1) gene fragment, and the assembly of whole NPEV genomes. A total of 159 NPEVs were characterized, representing 70.7% of the collected samples. The main capsid variants forming the predominant genotypic profile included E30 (n = 39, 24.3%), E6 (n = 31, 19.3%), and CVA9 (n = 25, 15.6%). Using NGS, we successfully assembled 13 whole genomes for E6, E30, EV-B80, CVA9, CVB5, E11, and EV-A71 and 3 partial genomes for E6 and EV-B87. This molecular-genetic analysis provides contemporary insights into the genotypic composition, circulation patterns, and evolutionary dynamics of the dominant NPEV associated with aseptic meningitis in the Ural Federal District and Western Siberia. The laboratory-based monitoring and epidemiological surveillance for genetic changes and evolutionary studies are important for improving prevention and healthcare. Full article

The reasons for disease outbreaks caused by Actinobacillus pleuropneumoniae (APP) in vaccinated pigs are often unknown and remain a challenge for farmers and veterinarians. One hypothesis for APP vaccine failure is the timing of APP vaccination during field or vaccine-induced viremia with Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), which may negatively affect the immune response to APP vaccination. In this study, fattening pigs were vaccinated with a modified live vaccine (MLV) against PRRSV either at the beginning of the fattening period (group G1) or six weeks later (group G2). All pigs were vaccinated against APP five days after the start of fattening, which coincided with MLV-PRRSV viremia in G1. Within both G1 and G2, four subgroups of pigs (n = 10) were vaccinated with three different APP vaccines or remained unvaccinated to assess serological responses to various APP antigens. MLV-PRRSV viremia had no significant effect on APP-ApxII (p = 0.127), APP-LPS (p = 0.120), or opsonophagocytic antibody responses on day 40 of fattening. Lung lesion scores at slaughter were significantly higher (p = 0.004) in pigs from G2 (1.82 ± 2.38) compared with those from G1 (0.65 ± 0.88). All APP vaccines elicited presumably protective opsonophagocytic antibodies. In conclusion, no effects of MLV-PRRSV viremia on serological responses following APP vaccination were observed. Full article

Overwinter Syndrome (OWS) affects grass carp (Ctenopharyngodon idellus) aquaculture in China, causing high mortality and economic losses under low temperatures. Failure of antibiotic therapies shows limits of the ‘low–temperature–pathogen’ model and shifts focus to mucosal barrier dysfunction and host–microbiome interactions in OWS. We compared healthy and diseased grass carp collected from the same pond using histopathology, transcriptomics, proteomics, and metagenomics. This integrated approach was used to characterize intestinal structure, microbial composition, and host molecular responses at both taxonomic and functional levels. Results revealed a three-layer barrier failure in OWS fish: the physical barrier was compromised, with structural damage and reduced mucosal index; microbial dysbiosis featured increased richness without changes in diversity or evenness, and expansion of the virobiota, notably uncultured Caudovirales phage; and mucosal immune dysregulation indicated loss of local immune balance. Multi-omics integration identified downregulation of lysosome-related and glycosphingolipid biosynthesis pathways at transcript and protein levels, with disrupted nucleotide metabolism. Overall gut microbial richness, rather than individual taxa abundance, correlated most strongly with host gene changes linked to immunity, metabolism, and epithelial integrity. Although biological replicates were limited by natural outbreak sampling, matched high-depth multi-omics datasets provide exploratory insights into OWS-associated intestinal dysfunction. In summary, OWS entails a cold-triggered breakdown of intestinal barrier integrity and immune homeostasis. This breakdown is driven by a global restructuring of the gut microbiome, which is marked by increased richness, viral expansion, and functional shifts, ultimately resulting in altered host–microbe crosstalk. This ecological perspective informs future mechanistic and applied studies for disease prevention. Full article

Canine Distemper Virus (CDV) is a highly contagious disease that affects a wide range of wildlife species, posing a serious threat to biodiversity and conservation efforts. Despite its ecological significance, the transmission dynamics of CDV in wildlife remain poorly understood, especially in tropical ecosystems. One of the main challenges in studying CDV transmission is the lack of reliable epidemiological data and the difficulty in capturing and monitoring wild animals for surveillance purposes. Thus, this study aims to develop a model to estimate the potential transmission of CDV in wildlife populations using spatial heat mapping and the basic reproduction number (R₀) as key indicators. A combination of field observation records, environmental data, and reported CDV cases were used to generate predictive heat maps and simulate disease spread across susceptible wildlife hosts. Results showed that certain environmental factors and animal density hotspots significantly contribute to higher transmission potential of CDV. Preliminary results suggest that high-risk zones can be identified based on overlapping wildlife movement corridors and human interface areas. This modeling approach offers a valuable tool to guide targeted monitoring, early detection and conservation strategies against CDV outbreaks in wildlife. 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

Lentinula edodes (shiitake) is a major edible and medicinal mushroom and a key component of the horticultural mushroom industry in East Asia. During April–June 2024 cropping season, a widespread blue mold outbreak was observed on bag-cultivated shiitake in Xixia County, Henan Province, China. Affected cultivation rooms showed extensive blue-green sporulation on the exposed surfaces of substrate blocks and on developing and mature fruiting bodies, leading to rapid loss of marketability. To clarify the etiology of this disease, we coupled field surveys with morphological, molecular, and pathogenicity analyses. Fifty-five Penicillium isolates were obtained from symptomatic cultivation bags. Three representative isolates (LE06, LE15, and LE26) were characterized in detail. Colonies on PDA produced velutinous to floccose mycelia with blue-green conidial masses and terverticillate penicilli bearing smooth-walled, globose conidia. Sequencing of four loci—the internal transcribed spacer (ITS1-5.8S-ITS2), β-tubulin (benA), calmodulin gene (CaM), and RNA polymerase II second largest subunit (rpb2)—followed by multilocus phylogenetic analysis placed all three isolates in a well-supported clade with the ex-type CBS 227.28 of Penicillium bialowiezense. Inoculation of healthy shiitake cultivation bags with conidial suspensions (1 × 10⁶ conidia mL⁻¹) reproduced typical blue mold symptoms on substrate surfaces and fruiting bodies within 40 days post inoculation, whereas mock-inoculated controls remained symptomless. The pathogen was consistently reisolated from diseased tissues and showed identical ITS and benA sequences to the inoculated strains, thereby fulfilling Koch’s postulates. This is the first confirmed report of P. bialowiezense causing blue mold on shiitake, and it expands the known host range of this species. Our findings highlight the vulnerability of bag cultivation systems to airborne Penicillium contaminants and underscore the need for improved hygiene, environmental management, and targeted diagnostics in commercial shiitake production. Full article

European plum (Prunus domestica L.) is widely cultivated worldwide, with China producing 6.8 million t annually (55% of the global total output). However, the Kashgar region of Xinjiang, China’s primary production area, has experienced outbreaks of brown spot disease caused by Alternaria alternata (Fr.) Keissl. Outbreaks of this disease severely hinder both domestic and global development of the European plum industry. Because this pathogen has a strong latent infection capability during the early stages of disease development, its early detection is important. We develop two detection methods targeting the ITS sequence of A. alternata: LAMP-Cresol Red chromogenic visible endpoint detection and LAMP-SYBR Green I real-time fluorescent detection. Both methods demonstrate high specificity for A. alternata, enabling stable detection of the pathogen in various plant samples; detection limits reach the femtogram (fg) level, significantly surpassing conventional PCR detection capabilities. Development of these highly efficient and precise early detection methods provides a solid foundation for sustainable development of China as a global hub of the European plum industry, and contributes significantly to global disease prevention, control, and industrial stability for this crop. Full article

Tilapia lake virus (TiLV) is a highly virulent pathogen that has caused substantial mortality in tilapia farms, particularly those with open-water systems. However, TiLV can also emerge and persist in closed environments, such as recirculating aquaculture systems (RAS), where environmental accumulation and repeated exposure may intensify infection and sustain outbreaks. In this case study, we conducted three field experiments to better understand TiLV dynamics among Nile tilapia in RAS. In experiment I, we quantified the TiLV levels in the fish, water, and sediment to compare outbreak and no-outbreak conditions and found that the TiLV concentrations in liver samples and the water were significantly higher in the outbreak ponds and positively correlated with increased fish mortality. In experiment II, we used a side-by-side field trial to evaluate the protective efficacy of a TiLV vaccine and its effects on the viral loads in the fish and aquatic environment during outbreaks. The vaccinated fish showed substantially lower cumulative mortality (16.7%) than the unvaccinated controls (37.7%), with a relative percent survival of 55.6%. Additionally, the TiLV concentrations in the pond water of the vaccinated group were significantly lower. In experiment III, we compared the TiLV patterns between RAS and non-RAS operations to determine how water recirculation influences viral accumulation and outbreak severity. The results revealed limited viral accumulation and shorter disease outbreak duration in the non-RAS. Overall, our findings showed that the TiLV levels in the rearing water were closely linked with disease severity in the RAS-based tilapia hatcheries. Continuous water recirculation allowed the virus to build up in the system, which led to more prolonged outbreaks, while the non-RAS conditions with regular water discharge showed lower viral loads and faster recovery. The vaccinated fish had better survival rates and released less virus into the water, which helped reduce infection pressure across the ponds. Together, these results suggest that combining vaccination with good water management and molecular monitoring can provide a practical, noninvasive way to detect and control TiLV outbreaks in intensive farming systems. 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

Mumps virus (MuV) is a single-stranded, negative-sense RNA virus of the Family Paramyxoviridae. MuV is a highly contagious human pathogen that causes primarily mild symptoms, including hallmark swelling of the parotid glands. Severe cases can occur, leading to neurological complications, including deafness, meningitis, and encephalitis. The mumps vaccine, now included in combination with measles and rubella vaccines (MMR), was first made available in the 1960s. After its introduction, mumps incidence dropped dramatically to less than 500 cases annually in the US. However, even with long-standing vaccination programs, MuV continues to challenge the landscape of public health due to a resurgence of cases in the past several decades and a still present lack of approved antiviral drugs and treatments available for the disease. This review will explore the biology of MuV, focusing on how MuV replicates and interacts with the host immune system. Recent studies have also shed light on the role of protein phosphorylation in regulating viral RNA synthesis—particularly the dynamic interactions between the nucleoprotein (NP) and phosphoprotein (P)—offering new insights into how the virus controls its replication machinery both mechanistically and through utilizing host cell advantages. We also examine how the immune system responds to mumps infection and vaccination, and how those responses may vary across viral genotypes. Although the Jeryl Lynn vaccine strain has played a key role in controlling mumps for decades, outbreaks among vaccinated individuals have raised questions about the present vaccine’s efficacy against circulating and emerging genotypes and if novel strategies will be required to prevent future outbreaks. We review current epidemiological data, highlighting shifts in MuV transmission and genotype distribution, and discuss the need for updated or genotype-matched vaccines. By connecting molecular virology with real-world trends in disease spread and vaccine performance, this review aims to support ongoing efforts to strengthen mumps control strategies and inform the development of next-generation vaccines. Full article

During the summer of 2023, a spontaneous disease outbreak occurred in intensively stocked hybrid catfish (♀ channel catfish, Ictalurus punctatus × ♂ blue catfish, I. furcatus) in earthen ponds on a commercial aquaculture farm in South Texas. The farmer reported 50 to 80 dead fish per pond daily for a month. The fish were market size (1.0 ± 0.3 kg on average), resulting in substantial economic losses. Fifteen moribund fish were submitted for laboratory examination. Grossly, the fish showed distended abdomens, erythematous fins, and inflamed vents. Autopsy demonstrated visceral congestion, distended gastrointestinal tracts, and serosanguineous peritoneal effusion. Bacterial cultures from the internal organs revealed homogeneous bacterial growth after incubation. Presumptive biochemical characterization of the isolated bacteria identified Plesiomonas shigelloides. Further molecular confirmation was achieved by species-specific PCR amplification and 16S-rRNA sequencing. Juvenile catfish were experimentally challenged with the recovered isolates to fulfill Koch’s postulates. Moreover, an antibiogram was performed to evaluate the susceptibility of the isolates to a panel of FDA-approved antimicrobials. P. shigelloides isolates were pathogenic to channel catfish and alarmingly multidrug-resistant. We report here, for the first time, P. shigelloides infection in Texas commercial catfish aquaculture, emphasizing its significance as an emerging enteric pathogen that is difficult to treat with FDA-approved antimicrobials. Full article

Following the normalization of the COVID-19 pandemic, the focus of wastewater-based epidemiology (WBE) must be broadened from SARS-CoV-2 to encompass surveillance of other major infectious diseases, particularly for pathogens where conventional clinical monitoring systems exhibit inherent surveillance gaps. In this study, we conducted a continuous two-year WBE study (January 2023 to December 2024) across three high-population-density cities in Guangdong, China to establish epidemiological baselines for enteric diarrheal viruses. We analyzed monthly raw wastewater samples from major treatment plants using advanced molecular methods, including digital PCR (ddPCR) for viral load quantification and targeted high-throughput sequencing (tNGS) for genotypic analysis. Our findings revealed diverse circulation patterns among the monitored enteric viruses. Astrovirus (AstV) had the highest detection rate (100%), reflecting its broad endemic distribution, while Norovirus genogroup II (NoV GII) exhibited relatively high viral loads (median 4 × 10⁴ copies/mL) and presented explosive seasonal peaks (significant upward trend in spring.), highlighting its epidemic potential. Furthermore, distinct spatiotemporal patterns were observed, with Sapovirus showing a significant summer peak in Foshan city, contrasting with the winter/spring peaks in the other cities. The tNGS results demonstrated similar sensitivity to RT-PCR in virus detection, and sequencing analyses uncovered the co-circulation and periodic shifts in dominant viral genotypes, such as the emergence of multiple NoV and AstV lineages. This longitudinal WBE surveillance successfully established critical baseline data and demonstrated significant regional heterogeneity in viral circulation, providing essential, complementary data to inform public health strategies for preventing diarrheal outbreaks in urban settings. Full article

Many emerging and re-emerging infectious diseases have been observed over the last few decades around the globe due to population growth, international travel, environmental changes, and microbial adaptation and evolution, despite advances in the medical field. The spread of these diseases is related to complex interactions between pathogens and their hosts. Accordingly, this review summarises current knowledge on infection development and discusses methods used for detection and modeling. Recent studies have revealed the limitations of two-dimensional models and increasingly rely on 3D systems, including spheroids, organoids, and organ-on-a-chip systems, that offer more realistic tissue environments, allowing researchers to more effectively study host–pathogen interactions. Overall, the integration of complementary approaches and the development of 3D models are crucial for enhancing diagnosis, developing new therapeutic approaches, and strengthening control strategies of emerging outbreaks. Full article

Aquaculture has been established as a sustainable alternative to traditional fisheries, which face challenges such as overexploitation and environmental degradation. However, disease outbreaks, often caused by poor farming conditions, pollution, and environmental stress, remain a major concern, leading to economic losses and increasing the risk of antibiotic resistance due to the overuse of antibiotics. Therefore, it is crucial to seek new strategies that improve fish health and well-being, preventing drug resistance and promoting sustainable practices. GHRP-6, a synthetic growth hormone-releasing peptide that mimics ghrelin, has shown potential immunostimulatory properties and feed efficiency in fish. In this study, we evaluated the effects of orally administered GHRP-6 in an oil-based formulation on juvenile tilapia (Oreochromis sp.) challenged or unchallenged with Pseudomonas aeruginosa. We assessed its influence on immune gene expression and digestive enzyme activity. The results demonstrated that GHRP-6 treatment significantly enhanced growth performance (weight and length), reduced in vivo bacterial load after infection, and modulated key genes related to innate and adaptive immunity in the gills, intestine and head kidney. In addition, our results demonstrated, for the first time, a direct link between a growth hormone secretagogue in fish and the modulation of specific enzyme activity in the gut following a bacterial challenge. These findings highlight the potential of GHRP-6 as a dietary immunomodulator and growth promoter in fish farming, offering a promising strategy to reduce antibiotic usage and promote more sustainable aquaculture practices. Full article

Background: Mosquito-borne viral diseases are a growing global health threat, and artificial intelligence (AI) and machine learning (ML) are increasingly proposed as forecasting tools to support early-warning and response. However, the available evidence is fragmented across pathogens, settings and modelling approaches. This review provides, to the best of our knowledge, the first comprehensive comparative assessment of AI/ML models forecasting mosquito-borne viral diseases in human populations, jointly synthesising predictive performance across model families and appraising both methodological quality and operational readiness. Methods: Following PRISMA 2020, we searched PubMed, Embase and Scopus up to August 2025. We included studies applying AI/ML or statistical models to predict arboviral incidence, outbreaks or temporal trends and reporting at least one quantitative performance metric. Given the substantial heterogeneity in outcomes, predictors and time–space scales, we conducted a descriptive synthesis. Risk of bias and applicability were evaluated using PROBAST. Results: Ninety-eight studies met the inclusion criteria, of which 91 focused on dengue. The forecasts spanned national to city-level settings and annual-to-weekly resolutions. Across classification tasks, tree-ensemble models showed the most consistent performance, with accuracies typically above 0.85, while classical ML and deep-learning models showed wider variability. For regression tasks, errors increased with temporal horizon and spatial aggregation: short-term, fine-scale forecasts (e.g., weekly city level) often achieved low absolute errors, whereas long-horizon national models frequently exhibited very large errors and unstable performance. PROBAST assessment indicated that most studies (63/98) were at high risk of bias, with only 24 judged at low risk and limited external validation. Conclusions: AI/ML models, especially tree-ensemble approaches, show strong potential for short-term, fine-scale forecasting, but their reliability drops substantially at broader spatial and temporal scales. Most remain research-stage, with limited external validation and minimal operational deployment. This review clarifies current capabilities and highlights three priorities for real-world use: standardised reporting, rigorous external validation, and context-specific calibration. Full article