Search Results (3,723)

Rabies is a fatal zoonotic disease once clinical symptoms develop. In Europe, sustained animal rabies control programs have led to a marked decline in animal rabies and subsequently human rabies cases; however, sporadic infections continue to occur. In July 2025, a fatal case of autochthonous (locally acquired) human rabies was confirmed in Romania following a stray dog bite in a patient who did not receive post-exposure prophylaxis (PEP). Here, we report the first molecular characterization of a human rabies virus (RABV) strain isolated in Romania and place it in the context of contemporaneously circulating animal-derived RABV strains. Rabies virus infection was confirmed intra vitam by fluorescent antibody testing and both conventional and real-time RT-PCR on cerebrospinal fluid and saliva, with postmortem confirmation on skin and brain tissue. Whole-genome sequencing was performed on the human isolate and on 22 animal-derived RABV strains collected in northern Romania in 2025. Phylogenetic analyses revealed that all recent Romanian sequences clustered within the North-East European (NEE) rabies virus phylogenetic group and segregated into two geographically distinct genetic clusters: a north-western cluster, closely related to strains from Slovakia and Poland, and a larger north-eastern cluster, linked to viruses circulating in eastern Romania and the Republic of Moldova. The human-derived RABV genome was grouped within the north-eastern cluster and showed the highest genetic similarity to animal viral strains from the same geographical area, supporting a local transmission event. This demonstrates the importance of integrating human viral genomic data into the national rabies surveillance framework. Full article

Pigeonpox is a significant infectious disease caused by Pigeonpox virus (PPV), which severely impacts the pigeon industry. Current control methods primarily rely on heterologous vaccines, such as those derived from avian poxviruses, but their protection is limited, creating an urgent need for the development of a specific vaccine. In this study, 720 samples collected from several regions of China between 2022 and 2023 were tested for PPV, followed by virus isolation, identification, and genetic evolutionary analysis. Based on these findings, complete genome sequencing and attenuation of the representative BJ-02 isolate were conducted, and the potential of this strain as a candidate for an attenuated vaccine was preliminarily evaluated. The survey showed PCR positive rates of 9.05%, 16.11%, and 12.50% in samples from Beijing, Guangdong, and Hainan, respectively. Six viral strains were isolated, all of which produced typical lesions on chorioallantoic membranes (CAM) and chicken embryo fibroblasts (CEF). Phylogenetic analysis based on the P4b gene revealed that the six viruses clustered within the same evolutionary branch, closely related to PPV and penguinpox virus strains from South Africa, India, and Taiwan, China. Complete genome sequencing of the BJ-02 strain showed its genomic structure to be similar to that of other fowlpox viruses, with some differences. After serial passage in CAM, PEF and CEF, the BJ-02 SD55 high-passage strain adapted well to in vitro culture, exhibited significantly reduced pathogenicity in chicken embryos and pigeons, and showed no reversion to virulence after five consecutive back-passages. Animal immunization tests demonstrated that the BJ-02 SD55 suspected attenuated strain induced specific antibodies and provided 100% protection against challenge with the virulent strain. In conclusion, PPV is widely prevalent in China. The BJ-02 strain, successfully isolated and attenuated through serial passage, demonstrates excellent immunogenicity and high safety, making it a promising candidate for a specific pigeonpox vaccine. Additionally, the complete genome characterization of BJ-02 contributes to the avian poxvirus genome database and provides critical data to support research on viral pathogenesis and the development of viral vector vaccines for avian and potentially mammalian species. Full article

Plant viruses pose serious threats to global crop production, and members of the genus Tobamovirus are particularly problematic due to their environmental stability, efficient mechanical transmission and rapid global spread. Tomato brown rugose fruit virus (ToBRFV) has emerged as one of the most damaging tobamovirus affecting tomato, a crop of major economic importance worldwide. ToBRFV has been reported in more than 45 countries, including Portugal. However, to date, no peer-reviewed molecular characterization of local isolates has been published, and official records classify its presence in Portugal as transient. This study confirms the occurrence of ToBRFV and provides the first comprehensive genomic and phylogenetic characterization of local virus isolates in Portugal. RNA-seq generated 192,852,438 reads, of which 103,882,115 (58.9%) mapped to ToBRFV, allowing reconstruction of a complete 6393 nt viral genome. A second full-length consensus sequence was independently obtained from the same composite sample using an overlapping Sanger sequencing strategy, differing by only two SNPs. Comparative genomic, functional, structural, and phylogenetic analysis revealed low diversity, with most variation located in replicase-coding regions, while movement and coat protein genes remained highly conserved. Nucleotide-based phylogenies resolved geographically structured clades, although the Portuguese sequences formed a strongly supported subclade with a Chinese isolate. These findings support recent global dissemination of ToBRFV and reinforce the importance of integrated surveillance and genomic monitoring for effective virus management. Full article

Elaeocarpus sylvestris (Lour.) Poir., an evergreen tree native to East and Southeast Asia, has gained increasing scientific attention owing to its broad pharmacological properties. Traditionally used in East Asian medicine to treat inflammation, fever, and infectious diseases, modern research has revealed diverse bioactivities, including potent antioxidant, anti-inflammatory, antiviral, anticancer, antidiabetic, and immunomodulatory effects. This therapeutic potential is primarily attributed to its rich phytochemical composition, particularly polyphenols such as geraniin, 1,2,3,4,6-penta-O-galloyl-β-D-glucose and quercetin. This review particularly focuses on the chemistry of E. sylvestris, summarizing structurally elucidated compounds, including hydrolysable tannins, flavonoids, and triterpenoids, along with recent insights into the structure–activity relationships that underpin these antiviral, antioxidant, and anticancer activities. Recent studies have demonstrated substantial antiviral efficacy of E. sylvestris extracts and isolated compounds against major human pathogens, including herpesviruses, influenza A virus, and SARS-CoV-2, supported by in silico, in vitro, in vivo, and early-phase clinical evaluations. Its cosmeceutical applications, including antioxidant, skin-whitening, and blue-light protective effects, further highlight its multifunctional potential. To our knowledge, this is the first comprehensive review summarizing the phytochemistry, pharmacological activities, therapeutic potential, and cosmeceutical applications of E. sylvestris. Despite these promising findings, challenges remain in elucidating precise molecular mechanisms, pharmacokinetics, and clinical validation. This review identifies current research gaps and future directions necessary to advance E. sylvestris as a scientifically validated natural therapeutic resource. Full article

Background: Hemodialysis patients are particularly vulnerable to hepatitis B virus (HBV) due to immunosuppression and repeated vascular access. While universal childhood vaccination has reduced population-level HBV prevalence, dialysis units require tailored prevention and monitoring strategies. This study aimed to characterize HBV serologic profiles, evaluate immune responses, and assess the kinetics of antibody waning in a diverse hemodialysis population. Methods: We retrospectively analyzed 565 adult hemodialysis patients (2015–2024), assessing HBV seroprevalence, seroconversion, booster response, and antibody waning. Subgroup comparisons were made by ethnicity and birth cohort (pre- vs. post-1992 national vaccine rollout). Time-to-waning analyses were performed using Kaplan–Meier methods. Results: HBsAg and anti-HBc were positive in 4.1% and 31.7% of patients, respectively; 3.7% were HCV seropositive. No HBsAg seroconversions occurred, and 2.1% of initially anti-HBc-negative patients seroconverted. Among patients with isolated anti-HBc, 80.9% developed protective anti-HBs titers, and none became HBsAg- or HBV DNA-positive. Waning anti-HBs titers occurred in 67.5% (median: 7.3 months), with 87.4% demonstrating a serologic response following documented vaccine delivery. Patients born after 1992 showed higher isolated anti-HBs positivity and lower anti-HBc prevalence. Ethnic subgroup analysis showed higher exposure rates but similar booster response among minority patients. Conclusions: HBV serologic profiles in this hemodialysis cohort reflected the interplay of immunosuppression, vaccination practices, and evolving epidemiologic trends. Subgroups exhibited variable vaccine responses, differing patterns of antibody waning, and a low incidence of new infections. These findings support tailored, population-specific HBV monitoring and prevention strategies in dialysis care. Full article

SARS-CoV-2 is a zoonotic virus with a proven ability to infect various animal species, including domestic cats. In the post-pandemic period of COVID 19, limited data still exist on the clinical course, shedding of infectious virus and diagnostic features in cats. The aim of this study was to investigate the spread of SARS-CoV-2 in cats in 2023, the clinical manifestations of the infection, the diagnostic algorithm, including molecular detection of viral components, the differential diagnosis of co-infection with FHV, FCV, Mycoplasma spp. and Chlamydia felis, serology, and the isolation of infectious SARS-CoV-2. The immunomodulatory therapy in animals with a standalone SARS-CoV-2 infection was applied. The study included oropharyngeal, conjunctival and nasal swab samples from 102 domestic cats with clinical signs. Of them, 20.6% (21/102) were positive for SARS-CoV-2, with 16.67% (17/102) of the cats showing various variants of co-infection with FHV, FCV, Mycoplasma spp. and Chlamydia felis. Four of the cats had a standalone SARS-CoV-2 with mild clinical manifestations that included serous discharges from the eyes, without change in the general condition. The virus was isolated from these samples. These four cats and their owners were positive for antibodies to the virus, and the owners were PCR-negative. The treatment of SARS-CoV-2 infection included the preparations Viusid, RX immunosuport, Vetomun and Lisymun. This is one of the first post-pandemic studies covering FHV, FCV, Mycoplasma spp. and Chlamydia felis in domestic cats with SARS-CoV-2 infection and further expands on the essential main idea including the specified pathogens of interest. Full article

Monkeypox (Mpox), caused by the monkeypox virus (MPXV), has re-emerged as a significant global public health concern, particularly following the 2022 outbreaks. Understanding its transmission dynamics is essential for designing effective control strategies. In this study, we develop and analyze a deterministic compartmental model that captures both human-to-human and rodent-to-human transmission pathways in order to better reflect the zoonotic nature of the disease. The model is investigated using qualitative and quantitative analytical techniques, including stability analysis, bifurcation theory, and sensitivity analysis. The basic reproduction number, $R_0$, is derived and used to determine threshold conditions for disease persistence or eradication. We show that the disease-free equilibrium is globally asymptotically stable when $R_0<1$, while an endemic equilibrium exists and is stable when $R_0>1$. Furthermore, the model exhibits backward bifurcation, indicating that reducing $R_0$ below unity may not be sufficient for disease elimination. Sensitivity analysis identifies key parameters driving transmission, particularly the rodent-to-human and human-to-human contact rates. Numerical simulations further demonstrate that reducing cross-species transmission and improving isolation of infected individuals significantly decrease disease burden. These findings highlight the complexity of Mpox transmission and emphasize that effective control requires not only lowering $R_0$, but also targeting critical transmission pathways. This study provides useful insights for public health planning by identifying priority intervention strategies such as minimizing rodent–human interactions and strengthening isolation measures. Full article

Getah virus (GETV), a mosquito-borne virus capable of infecting multiple economically important animal species, poses a potential epidemic risk. In May 2024, one pig farm from Heyuan, Guangdong Province, China, suffered reproductive disorders in sows and diarrhea in newborn piglets. Out of the six blood samples that were collected, three tested strongly positive for GETV, yielding a positivity rate of 50%. Moreover, a GETV strain (designated GDHYLC2024) was successfully isolated and identified. The viral titer of GDHYLC2024 was 10^7.687 TCID₅₀/mL in Vero cells. Its genome was composed of 11,688 bases in length. Interestingly, compared with GDHYLC23, it had no unique 32-nucleotide repeat insertion in 3′ non-coding region. However, phylogenetic analysis showed that GDHYLC2024 and GDHYLC23 clustered in genotype III. Animal infection experiments demonstrated that the GDHYLC2024 strain was highly pathogenic to 4-day-old piglets, which caused obvious clinical symptoms including fever, depression, anorexia, periorbital edema, ataxia, and three deaths out of a total of five individuals in the infection group. This study reported re-emergence of GETV in the same region of Guangdong Province, China. The above findings suggest that GETV continuously poses a threat to farm pig’s health and has genetic diversity. Full article

Aujeszky’s disease (AD), caused by suid herpesvirus 1 (pseudorabies virus, PRV), is a highly contagious infection primarily affecting swine, with wild boars serving as an important reservoir in Europe. Spillover infections in non-suid species, including carnivores, are rare but typically fatal and of epidemiological concern. This study presents the first case of AD in a grey wolf (Canis lupus) in Central Europe with genomic characterization. The 8-month-old wolf was found in the Carpathians (SE Poland), moribund with acute neurological signs, and euthanized for animal welfare reasons. Necropsy revealed no pathognomonic gross lesions. Molecular analyses of tissues confirmed the presence of PRV DNA using real-time PCR, and virus isolation was successful. Genomic analysis revealed that the PRV isolate clustered within genotype I, the predominant circulating genotype in Europe. However, due to the limited availability of reference PRV genome sequences from European wildlife, the precise geographic origin and transmission pathways of this strain could not be fully resolved. In the presented case, wild boars were considered a possible source of infection. This highlights the potential for PRV transmission to apex predators. This study emphasizes the importance of systematic surveillance of PRV in wildlife and the need for expanded genomic databases of PRV strains. Full-genome sequencing is crucial for improving the understanding of PRV transmission. Full article

Ticks serve as primary vectors for a wide array of RNA viruses, yet the diversity and distribution of tick-associated RNA viruses remain incompletely characterized in Hebei province. To address this gap, we conducted a systematic metatranscriptomic investigation of 986 ticks representing six species, collected from the diverse ecological landscapes of Hebei Province in northern China. Our analysis recovered 25 complete or near-complete viral genomes spanning 12 families, including Phenuiviridae, Flaviviridae, and Nairoviridae. Of critical public health significance, we identified Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) in both Haemaphysalis longicornis and Dermacentor nuttalli. Phylogenetic reconstruction revealed marked geographic stratification where strains from the coastal plains clustered with the dominant Genotype F, while those from the mountainous north formed a characteristic and divergent lineage phylogenetically linked to isolates from Inner Mongolia. Furthermore, a novel viral agent provisionally named Zhangjiakou Hepacivirus was discovered in Haemaphysalis japonica. This virus shared less than 80% nucleotide identity with the rodent-associated Hepacivirus P, consistent with a rodent origin and possible cross-species transmission. Collectively, these findings reveal descriptive variation associated with vector identity, physiological status, and ecological context in shaping viral evolution and underscore the need for continuous metagenomic surveillance to mitigate emerging tick-borne disease risks within a One Health framework. Full article

This study investigated the in vitro replication kinetics and molecular characteristics of five field isolates of bovine viral diarrhea virus (BVDV) representing subgenotypes 1b, 1d, and 1f, currently circulating in Hungary. We compared cytopathogenic (cp) and non-cytopathogenic (ncp) biotype pairs using digital PCR (dPCR) and virus titration. While dPCR showed higher genome copy numbers for cp isolates, virus titration revealed comparable or lower infectious titers, suggesting the accumulation of replication-incompetent viral particles during the infection cycle. Molecular analysis identified (novel) amino acid substitutions in Npro, capsid, and NS4B regions, although typical large-scale genome rearrangements were absent. These findings demonstrate that biotype differences are molecularly complex and subgenotype-dependent. Our results emphasize that relying on a few genetic markers is insufficient for biotype categorization, necessitating comprehensive characterization in BVDV surveillance programs. This complexity must be considered when designing vaccines or control programs, especially in regions with diverse circulating strains. Full article

Despite viral suppression with antiretroviral therapy (ART), reservoirs of Human Immunodeficiency Virus (HIV) persist in anatomical compartments throughout the body, including the brain. We have previously demonstrated that the HIV long terminal repeats (LTRs) isolated from the brains of non-virally suppressed people with HIV (PWH) are phylogenetically and functionally distinct from those isolated from matched peripheral tissue. While intact, transcriptionally competent HIV genomes persist within the brains of virally suppressed PWH, whether HIV LTRs are intact, functional, and compartmentalized relative to the periphery, as in non-virally suppressed PWH, remains unclear. HIV LTRs were extracted from frontal cortex post-mortem brain and matched peripheral tissues of virally suppressed PWH (n = 5). Following single-genome amplification, sequences were phylogenetically analyzed and transcriptional activity was assessed. In contrast to non-virally suppressed PWH, LTR sequences failed to compartmentalize between the brain and peripheral compartments. Identical LTR sequences were observed across brain and peripheral tissues in 2/5 PWH. While the LTRs remain transcriptionally active, mutations, insertions and deletions predicted to reduce transcription factor binding affinity at key binding sites, including C/EBP, NF-κB, and Sp1 sites, were observed and found to result in reduced basal transcriptional activity. The role of these mutations in latency and viral persistence remains unclear. Full article

Porcine reproductive and respiratory syndrome virus genotype 1 (PRRSV-1), particularly the BJEU06-1-like subgroup, has shown increasing detection in China; however, the biological characteristics of newly emerging strains in southwestern regions remain insufficiently defined. Therefore, this study aimed to isolate and characterize a PRRSV-1 strain circulating in Southwestern China and to compare its biological properties and pathogenicity with those of a representative NADC30-like PRRSV-2 strain. In this study, a PRRSV-1 field strain (CDAC-SC2025) was isolated from a lung sample collected in Sichuan Province and characterized by immunofluorescence, full-genome sequencing, and maximum-likelihood phylogenetic analysis. Recombination was assessed using RDP4 and SimPlot (Baltimore, MD, USA). Pathogenicity was evaluated in newborn piglets following intranasal challenge, with monitoring of clinical signs, viremia, viral shedding, tissue viral loads, and histopathology. CDAC-SC2025 clustered within the BJEU06-1-like subgroup and showed the closest relationship to HENZMD-10 without detectable recombination. A three-amino-acid deletion (373–375 aa) was identified in nsp2. In vivo, CDAC-SC2025 induced fever, respiratory signs, growth retardation, and mortality, but the onset of death was delayed and lesion severity was lower than those caused by the NADC30-like strain DJY. Both strains exhibited predominant viral loads in the lung and tonsils, although quantitative differences were observed across tissues. Histopathology revealed moderate lesions in CDAC-SC2025-infected piglets compared with more severe multisystemic damage caused by DJY. These findings provide updated data on the biological properties of BJEU06-1-like PRRSV-1 circulating in southwestern China. Full article

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne infectious disease with high case-fatality rates in East Asia. The causative agent, SFTS virus (SFTSV; also known as Dabie bandavirus), exhibits genotype-dependent differences in pathogenicity. However, infection models that recapitulate these variations and can be applied for vaccine and therapeutic evaluation are still lacking. In this study, we assessed the pathogenicity of two Korean SFTSV isolates representing the F and B genotypes in a murine infection model. Wild-type C57BL/6 and IFNAR knockout (IFNAR−/−) mice were intraperitoneally infected with two different doses of SFTSV (2 and 2 × 10⁻¹ FFU). All C57BL/6 mice survived regardless of viral genotype or dose. In IFNAR−/− mice, infection with either F- or B-type virus at the 2 FFU dose resulted in mortality beginning at 5 days post-infection, with all mice succumbing within 6 days. At the higher dose (2 × 10⁻¹ FFU), mortality differed by genotype: B-type infection led to 20% lethality, whereas F-type infection caused 40% lethality by day 5. Infected and deceased mice exhibited body weight loss as a characteristic clinical outcome. Collectively, these findings demonstrate genotype-associated differences in SFTSV pathogenicity in mice and establish a murine challenge model that may be useful for the preclinical evaluation of candidate vaccines and antiviral agents. Full article

Seasonal influenza A evolves quickly through mutations in haemagglutinin (HA) and neuraminidase (NA), which can reduce vaccine match and lower protection. Many sequence-only models do not link codon-level mutations to three-dimensional (3D) protein context and long-term evolutionary signals within one scoring framework. This study presents TRIAD-Influenza (TRIAD: Token–Residue–Integrated Architecture for Drift), a multi-view transformer that combines (i) codon- and residue-level sequence representations, (ii) structure-derived residue interaction features from predicted HA/NA models, and (iii) an embedding-space phylogeny that captures cluster and drift context. The pipeline curates more than $3\times {10}^5$ paired HA/NA coding sequences from the NCBI Virus resource (2010–2024) using strict quality control and codon-aware alignment and predicts 3D structures for nearly all unique HA and NA proteins to build contact graphs and surface/stability descriptors. TRIAD-Influenza outputs a continuous, structure-aware risk score for each HA/NA pair and produces interpretable mutation hotspot maps using gradient saliency and a contact-weighted mutation risk index (CMRI). On rolling-origin temporal cross-validation and for a temporally held-out internal test window with strong class imbalance (∼3.4% high-risk), the model shows strong ranking performance (AUROC $\approx 0.89$; AUPRC $\approx 0.44$; Brier score $=0.069$) while operating at surveillance speed (median latency $\approx 1.6$ ms per HA/NA pair). External validation on independent GISAID/Nextstrain cohorts (2023–2024; 5000 isolates) preserves discrimination (AUROC $\approx 0.85$–$0.86$). Predicted risk scores correlate with experimental haemagglutination inhibition (HI) antigenic distances (Spearman $\rho$ up to ≈0.82 at the virus-aggregated level), and CMRI hotspots enrich known epitope and deep mutational scanning escape residues (odds ratios $\approx 2.7$–$3.6$). Overall, token–residue–phylogeny coupling enables rapid, structure-aware prioritisation of emerging influenza A HA/NA sequences and delivers compact hotspot maps for expert review and targeted experiments. Full article