Background: Herpes zoster (HZ), caused by the reactivation of varicella-zoster virus (VZV), primarily affects elderly populations worldwide. Although current recombinant HZ vaccines show strong immunogenicity, their high cost and potential side effects may limit their widespread use. Therefore, developing a cost-effective HZ vaccine with improved safety profiles would have significant clinical and public health implications. Methods: Building upon our previously optimized truncated gE (tgE350) from VZV, we developed the tgE350 + Fe nanoparticle vaccine using SpyTag/SpyCatcher covalent conjugation. The tgE350 protein (with a SpyTag tag) and the Fe protein (with a SpyCatcher tag) were expressed in HEK293F and E. coli BL21, respectively, enabling spontaneous nanoparticle assembly. Protein expression and nanoparticle formation were confirmed through SDS-PAGE and negative-stain electron microscopy. BALB/c mice were inoculated with either tgE350 + Fe or tgE350 combined with Al and CpG adjuvants. Immune responses were evaluated using ELISpot and flow cytometry for cellular immunity, along with ELISA, VZV microneutralization, and fluorescent antibody membrane antigen (FAMA) assays for antibody titers. Histopathological examination of major organs ensured vaccine safety. Results: Compared with the truncated vaccine tgE350, the nanoparticle vaccine tgE350 + Fe significantly enhanced VZV neutralizing antibodies and specific antibody responses in mice without causing significant changes in lymphocyte populations (no difference from the control group). Moreover, the tgE350 + Fe group had significantly more lymphocytes secreting IFN-γ, IL-2, and IL-4 than the tgE350 group. No apparent pathological damage was observed in the heart, liver, spleen, or lungs of mice in any experimental group. Conclusions: This experiment successfully developed the HZ nanoparticle vaccine tgE350 + Fe. It enhanced VZV-specific neutralizing antibodies, generated better cellular and humoral immune responses, and demonstrated good safety.

Nipah virus, a highly lethal zoonotic paramyxovirus with a case‑fatality rate of 40-75%, poses a formidable threat to global health security. This review synthesizes its evolving epidemiology, contrasting the Malaysian and Bangladesh‑India strains, and dissects molecular pathogenesis focusing on G/F glycoprotein recognition of ephrin receptors and the multi‑layered immune evasion mediated by P gene products. Phylogenetic analyses reveal 8-10% nucleotide divergence between lineages, with positive selection in the G protein that may compromise vaccine cross‑protection. Ecological risk amplifiers-deforestation and climate‑driven habitat loss-reshape spillover dynamics through spatial expansion of bat foraging, prolonged risk windows, and pathway diversification. Deforestation exceeding 5% per decade correlates with a 2-3‑fold increase in spillover events in Bangladesh. A dynamic risk‑assessment framework is proposed that views pandemic potential as the convergence of viral evolution, ecological amplification, and geographic expansion-from South Asia to Pteropus‑bearing regions worldwide, including unrecognized risks in China. Current medical countermeasures (mRNA vaccines, m102.4 antibody, remdesivir) and deployment challenges (genetic diversity, biosafety level 4 constraints, regulatory dependence on the "Animal Rule") are evaluated. The conclusion calls for a "One Health"‑informed global defense system anchored on four pillars: intelligent forecasting that integrates ecological data; a broadly protective countermeasure repository; democratized rapid diagnostics; and translational bridges linking molecular insights to actionable interventions. Strengthening global collaboration is imperative to prevent Nipah virus from escalating into a pandemic.

This study investigates the codon usage characteristics of Japanese encephalitis virus (JEV) genotype 5 (G5). Based on 339 complete JEV genome sequences, we systematically compared the codon usage patterns of G5 with other genotypes (G1-G4) using a multi-faceted approach, including evolutionary analysis, nucleotide composition, Relative Synonymous Codon Usage (RSCU), Principal Component Analysis (PCA), Effective Number of Codons Plot analysis (ENC-Plot), Parity Rule 2 analysis (PR2), Neutrality plot analysis, dinucleotide abundance analysis and Codon Adaptation Index analysis (CAI). The results indicate that G5 forms a distinct evolutionary branch, with both its overall GC content (50%) and GC content at the third codon position (GC3, 53%) being lower than those of other genotypes. RSCU analysis revealed a preferential use of A/U-ended codons in G5, indicating a trend towards reduced GC3 usage. ENC analysis demonstrated a stronger codon usage bias in G5 (mean ENC = 54.2). Furthermore, ENC-plot, PR2, and neutrality plot analyses collectively suggested that G5 is subject to stronger natural selection pressure. Analysis of dinucleotide abundance showed a significant increase in CA values in G5, while CAI analysis indicated higher translational efficiency in human hosts compared to Culex mosquito hosts. Our findings suggest that G5 JEV, potentially through reduced Cytosine-phosphate-Guanine (CpG) usage and optimized codon preference, may enhance its capabilities for immune evasion and host adaptation, and could possess the potential for efficient replication in humans or other mammalian hosts. This research provides crucial theoretical insights into the molecular evolutionary mechanisms of G5 JEV and informs related vaccine development.

The recent emergence of the genotype five Japanese encephalitis virus (G5 JEV) has once again drawn public attention to public health concerns. Plaque assay analysis of G5 JEV parental strain XZ0934 revealed two distinct plaque morphologies. To investigate this phenotypic heterogeneity, we performed single-plaque purification and isolated two strains, designated as XZ0934-L (large plaque) and XZ0934-S (small plaque). Subsequently, deep mutational scanning revealed an amino acid mutation at position 138 (E138K) in the E protein of the XZ0934-S strain. Viral titer determination and plaque morphology analysis showed that the titers of XZ0934-L and XZ0934-S in BHK-21 cells were 107.06 PFU/mL and 107.35 PFU/mL, respectively, with plaque diameters of 0.87 ± 0.12 mm and 0.38 ± 0.08 mm. However, while both strains induced cytopathic effects across six cell lines used in this study, XZ0934-S produced markedly weaker CPE than XZ0934-L in N2a cells. Spatial modeling predicted that the E138K substitution did not significantly alter the overall conformation of the E protein. In contrast, transcriptomic analysis demonstrated that infections with different JEV genotypes induced significantly distinct host gene expression profiles in N2a cells. The XZ0934-S strain caused the mildest transcriptional perturbations, and the perturbation of regulatory pathways was markedly weaker than those of the XZ0934-L strain. Previous studies have suggested that the E138K mutation can attenuate the neurovirulence of JEV. This study provides the first comprehensive in vitro characterization of an E138K mutant in G5 JEV. The XZ0934-S mutant strain, given its small plaque phenotype and reduced transcriptional impact, represents a promising candidate for further vaccine development. Future studies should rigorously evaluate its safety profile, genetic stability, and immunogenicity in animal models.

During the 2023 surveillance of mosquito-borne viruses in Ningxia Hui Autonomous Region, a strain of Umatilla virus (UMAV) was isolated from a pool of Culex pipiens pallens (NX23166) collected in Xiji County and cultured in C6/36 cells. Electron microscopy revealed that NX23166-infected mosquito cells showed approximately 70-nm virus particles, typical of the genus Orbivirus. Through next-generation sequencing, 10 double-stranded RNA (dsRNA) segments of the virus were obtained. Phylogenetic and homology analyses based on these sequences revealed that this strain was most closely related to the first Chinese isolate from Yunnan in 2013 (DH13M98) and an Australian isolate from 2015 (M4941_15). However, the VP3 protein of this strain showed the closest evolutionary relationship to a German isolate from 2019 (ED-I-205-19), with an amino acid sequence identity of 94.00%. In contrast, the identity of the VP3 protein to that of other strains ranged only from 47.38% to 51.49%, suggesting that these two strains may belong to the same serotype. Nevertheless, this hypothesis needs to be further verified by a serum neutralization test. Furthermore, transcriptome sequencing analysis showed that infection with the Ningxia isolate of UMAV induced significant temporal transcriptomic reprogramming in C6/36 cells. This reprogramming was characterized by early activation of innate immune responses such as the Toll signaling pathway and autophagy, followed by significant suppression of metabolic pathways, including oxidative phosphorylation in the mid to late stages of infection, demonstrating a molecular phenotype of coordinated immune activation and metabolic suppression. These results provide new insights into the genetic diversity and geographic distribution of the species UMAV.

Japanese encephalitis (JE), a mosquito-borne viral disease caused by the Japanese encephalitis virus (JEV), remains a significant public health threat in Asia. Although vaccination programs have successfully reduced the incidence of JE, challenges persist in the adult population, and the emergence of rare JEV genotypes poses additional risks. In this study, a phylogenetic analysis of the whole JEV genome sequence, along with a temporal–spatial analysis of isolates and a host–vector analysis, was used to examine the changes in JEV transmission dynamics before and after 2012. The results revealed persistent differences between the dominant G1 and G3 genotypes, as well as the re-emergence of G4 and G5 genotypes. Although JEV has been detected in non-traditional vectors and atypical mammalian hosts, Culex tritaeniorhynchus and pigs remain the primary vector and amplifying host, respectively. These findings underscore the need to enhance existing JEV genotype surveillance while addressing emerging threats from genotype diversity, host expansion, and geographic spread.

(1) Background: A safe and effective nucleic acid sample transportation method was developed that is suitable for underdeveloped areas which lack advanced sequencing capabilities, specifically for virus genomic sequencing and infectious disease monitoring. (2) Methods: This study evaluated the use of Flinders Technology Associates (FTA) cards for transporting amplified whole-genome DNA from 120 SARS-CoV-2-positive nasopharyngeal swab samples in Sierra Leone. Nucleic acid extraction and whole-genome amplification were conducted at a local laboratory. Amplified products were applied to FTA Elute cards for room temperature shipment to China CDC for elution and sequencing. (3) Results: The FTA card method achieved a 9.6% recovery rate for amplicons, sufficient for viral genome sequencing. In total, 86 (71.7%) high-quality SRAS-CoV-2 genomic sequences were obtained, with the majority reaching depths exceeding 100X. Sequence analysis revealed co-circulation of Delta, Omicron, and B.1 lineages. Higher Ct values in the original sample significantly reduced coverage and depth, with Ct ≤ 27; 73.6% of samples yielded effective sequences. (4) Conclusions: Transportation of amplified nucleic acid samples using FTA cards enables virus genomic sequencing in resource-limited areas. This approach can potentially improve local virus surveillance and outbreak response capabilities. Further optimizations could improve sequence recovery rate. Implementing this method could significantly enhance sequencing accessibility in underdeveloped regions.

Shanxi Tick Virus 2(SXTV2), a Tamdy group member of Orthonairovirus genus, Nairoviridae family, was initially identified through Next Generation Sequencing, with its pathogenicity and risk profile remaining unclear. This study reports the first successful isolation of SXTV2 from Haemaphysalis longicornis ticks collected from Hunchun City, China-a tri-border region between China, Russia, and North Korea. The isolated SXTV2 strain replicated and produced cytopathic effects in both Vero (primate) and SW-13 (human) cell lines. Electron microscopy revealed that SXTV2 particles are enveloped, surface-spiked, pleomorphic, and approximately 100 nm in diameter. Experimental inoculation in neonatal mice led to significant weight loss, liver injury and 100% mortality. In conclusion, this study marks the first successful isolation of the SXTV2 strain and exploring the animal model for member of Tamdy group orthonairovirus. These findings suggest the need for enhanced surveillance of SXTV2 zoonotic exposure and disease epidemic risks.

WUXV is phlebovirus transmitted by sandflies, which can cause death in suckling mice and infect humans and chickens. However, little is known about the pathogenicity and pathogenic mechanisms of animals. Therefore, BALB/c WT mice and BALB/c nude mice were infected with WUXV. No fatal diseases occurred except for weight loss among the BALB/c WT mice, while BALB/c nude mice observed significant neurological symptoms and death. The virus nucleic acid was detected in the organs and blood of both mice. The blood routine showed a significant increase in RDW, and IgM, IgG, and neutralizing antibodies were detected in the serum of the BALB/c WT mice, which were significantly higher than those of BALB/c nude mice. The inflammatory factors in tissues, and pathological section results, indicate that WUXV caused severe inflammatory reactions. In addition, we found that WUXV activates the inflammatory pathway by activating TLR5 and TLR9. Inhibition of TLR5 and TLR9 can eliminate the activation of NF-κb and downstream inflammatory factors. In summary, we systematically studied the pathogenicity and pathogenesis of WUXV infection in mice with different immune states, and found that TLR5 in mammalian cells can serve as RNA sensor, expanding our understanding of the virus.

Tick-borne encephalitis virus (TBEV) is a significant tick-borne flavivirus responsible for severe human diseases. Here, we analyzed the genetic diversity and evolutionary dynamics of TBEV using 263 genome sequences from the NCBI database and identified key amino acid mutations. TBEV sequences were classified into five genotypes—Baikalian, European, Far-Eastern, Himalaya, and Siberian—showing ORF nucleotide similarity of 81.5% to 88.0% and amino acid similarity of 93.0% to 96.4%. Extensive recombination between genotypes was not observed. Entropy analyses revealed highly variable sites distributed across the Baikalian (n = 2), European (n = 3), Far-Eastern (n = 5), and Siberian (n = 13) genotypes. Each genotype exhibited specific amino acid mutations. Positive selection analysis identified sites under selection in the full dataset (n = 2), as well as in the European (n = 6), Far-Eastern (n = 7), and Siberian (n = 4) genotypes. By integrating highly variable sites, shared genotype-specific mutations, and positively selected sites, we identified 37 key amino acid positions, primarily located on the surfaces of viral proteins. These positions may have a potential impact on protein function and pathogenicity, though further studies are required to validate and evaluate these effects comprehensively. This study provides the first comprehensive analysis of mutational landscapes across TBEV genotypes, uncovering potential critical mutations that may shape viral biology and pathogenicity, and offers valuable insights for further exploration of TBEV characteristics.

The NS1 protein of nine mosquito-borne flaviviruses, including Dengue virus 1-4, Japanese encephalitis virus, West Nile virus, Yellow fever virus, Tembusu virus, and Zika virus, shows distinct codon usage and evolutionary traits. Codon usage analysis shows notable base composition bias and non-conservatism in NS1, with distinct evolutionary traits from its ORF. Analysis of relative synonymous codon usage (RSCU) indicates that the NS1 genes exhibit non-conservative RSCU patterns within different mosquito-borne pathogenic flaviviruses. Principal component analysis (PCA) based on the RSCU values, effective number of codons (ENC)-GC3, and parity rule 2 analysis (PR2) plot analyses demonstrate the similarity in codon usage patterns of NS1 genes among different mosquito-borne pathogenic flaviviruses. The ENC-GC3 and PR2 results, along with neutrality and selection pressure analyses, confirm that natural selection, especially purifying selection, plays a primary role in shaping NS1 codon usage. In addition, NS1 is subject to stronger positive selection than ORF, resulting in higher host adaptability in its codon bias, such as higher CAI index, hydrophilicity, aromaticity, and low CpG usage. These features indicate that the codon usage pattern of NS1 plays a crucial role in viral adaptation and immune evasion mechanisms, supporting the design and optimization of NS1-based vaccines.

[This corrects the article DOI: 10.1016/j.imj.2025.100179.].

OBJECTIVES:This study investigated the potential beneficial effects of a probiotic candidate, Clostridium cochlearium 2316, in modulating physiological and metabolic markers in mice with high-fat diet-induced obesity (DIO). METHODS:C57BL/6 DIO mice were assigned to three groups (ad libitum): standard low-fat control (LF, 10% fat), high-fat diet (HF, 60% fat), and high-fat diet supplemented with approximately one billion CFU/day of CC2316 via daily oral gavage for 16 weeks. RESULTS:After 16 weeks, the CC group exhibited 17.3% lower body weight gain (p < 0.001) and significant fat mass decrease (p < 0.0001) compared to HF mice. Serum biochemistry showed that CC2316 supplementation resulted in a 27.7% reduction in fasting blood glucose (p < 0.05), a 58.4% reduction in fasting insulin (p < 0.01), and an 89.4% improvement in HOMA-IR score (p < 0.05). Furthermore, serum total cholesterol level decreased dramatically by 40.2% in the CC group (p < 0.001). Despite a higher caloric absorption rate (p < 0.001), CC mice demonstrated a significant beneficial shift in energy expenditure, characterized by an increased basal metabolic rate (p < 0.05), higher energy expenditure (p < 0.05), and an elevated respiratory quotient (RER) (p < 0.05), alongside increased physical activity (p < 0.05). CONCLUSIONS:This investigation strongly suggests that CC2316 supplementation mitigates the adverse effects of HFD-induced obesity by modulating whole-body energy metabolism, positioning it as a potential aid to lower risk factors associated with metabolic syndrome. The precise mechanisms linking the gut microbiome to altered energy substrate utilization are discussed and suggested for further investigation.

Backgroud: Coltiviruses are spherical, non-enveloped viruses with 12 double-stranded RNA segments, belonging to the family Spinareoviridae, and predominantly transmitted by ticks. This study isolated and characterized a novel coltivirus, designated Woodland tick reovirus (WLTRV), from Haemaphysalis concinna ticks collected in Helong City, Jilin Province, in Northeastern China. Methods: SW-13 and Vero cells were used to isolate WLTRV through three blind passages, while seven mammalian cell lines assessed viral growth. Viral morphology was observed by electron microscopy. Next-generation sequencing, 5ʹ and 3ʹ rapid amplification of cDNA ends were used to determine WLTRV whole genome sequences, and phylogenetic methods were used to characterize WLTRV. A real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect WLTRV RNA in ticks. Results: WLTRV grew and exerted cytopathic effects in human (SW-13 and 293T) and mouse (BHK-21 and N2A) cell lines, revealing its potential to infect mammals. Phylogenetic analysis based on RNA-dependent RNA polymerase sequences classified WLTRV within the genus Coltivirus, with a close evolutionary relationship to Tarumizu tick virus. The nucleotide and amino acid sequence homologies between WLTRV and Tarumizu tick virus across the 12 segments analyzed ranged from approximately 44.79% to 69.09% and 33.73% to 75.60%, respectively. WLTRV shared conserved the 5ʹ-terminal (GACAA/UU/A) and 3ʹ-terminal (UGCAGUC) consensus sequences of the genus Coltivirus genomes. Electron microscopy revealed WLTRV as spherical (diameter ∼80 nm), non-enveloped, and morphologically consistent with coltiviruses. Among the 4,717 ticks collected from six towns in the Yanbian Korean Autonomous Prefecture, WLTRV RNA was only detected in H. concinna (0.95% virus-carrying rate) but not in Haemaphysalis japonica, Haemaphysalis longicornis, Ixodes persulcatus, and Dermacentor silvarum. Conclusions: This study represents the first isolation and identification of WLTRV from H. concinna in the Yanbian Korean Autonomous Prefecture, providing new insights into the genetic diversity and evolution of the genus Coltivirus.

Backgrounds: A contemporary public health challenge is the increase in the prevalence rates of herpes zoster (HZ) worldwide. Methods: In this work, the gE gene structure was analyzed using bioinformatics techniques, and three plasmids of varying lengths, tgE537, tgE200, and tgE350, were expressed in Chinese hamster ovary (CHO) cells. These proteins were used to immunize BALB/c mice with Al/CpG adjuvant; ELISPOT and FCM were used to evaluate cellular immunity; and ELISA, VZV microneutralization, and FAMA assays were performed to detect antibody titers. Results: Target protein concentrations of 1.8 mg/mL for tgE537, 0.15 mg/mL for tgE200 and 0.65 mg/mL for tgE350 were effectively produced. The ability of the three protein segments to stimulate CD4+ and CD8+ T cells, as well as to cause lymphocytes to secrete IFN-γ and IL-4, did not significantly differ from one another. Both tgE537 and tgE350 were capable of generating VZV-specific antibodies and neutralizing antibodies, while tgE350 had the highest neutralizing antibody titer (4388). There was no equivalent humoral immune response induced by tgE200. Conclusions: The results of this investigation provide the groundwork for the creation of HZ recombinant vaccines using truncated proteins as antigens.

Emerging pathogenic tick-borne viruses (TBVs) have attracted a great deal of attention due to their significant impact on human and animal health. A novel orthonairovirus named Dadong virus (DDV) was isolated from Haemaphysalis concinna ticks in the Changbai Mountain region on the China-North Korea border. DDV can induce cytopathic effects in mammalian and human cell lines. Phylogenetic analysis showed that it belongs to the genus Orthonairovirus, family Nairoviridae, exhibiting 72.4%-81.3% nucleic acid identity to Tofla orthonairovirus, known to cause lethal infection in IFNAR KO mice. The first serological evidence of DDV circulating in cattle and mice was also obtained, with 4.0% (1/25) of cattle and 2.27% (1/44) of mice seropositive for DDV. Further investigations, including serological surveys using human samples, are required to assess the public health risk posed by DDV.

The causative agent of coronavirus disease 2019 (COVID-19), known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread accumulatively to 240 countries and continues to evolve. To gain a comprehensive understanding of the epidemiological characteristics of imported variants in China and their correlation with global circulating variants, genomic surveillance data from 11 139 imported COVID-19 cases submitted by Chinese provincial CDC laboratories between 2021 and 2022 were analyzed. Consensus sequences underwent rigorous quality checks, followed by amino acid mutations analysis using Nextclade. Sequences with satisfactory quality control status were classified according to the Pango nomenclature. The results showed that the dominant variants in imported cases reflected the global epidemic trend. An increase in the number of imported SARS-CoV-2 lineages monitored in China in the second half of 2022, and the circulating Omicron subvariants changed from the ancestral lineages of BA.5 and BA.2 into the lineages containing key amino acid mutations of spike protein. There was significant variation in the detection of Omicron subvariants among continents (chi(2) = 321.968, p < 0.001) in the second half of 2022, with four lineages (BA.2.3.7, BA.2.2, BA.5.2.7, and XBB.1.2) identified through imported surveillance mainly prevalent respectively in Taiwan, China, Hong Kong SAR, China, Russian Federation, and Singapore. These findings revealed the alterations in circulating imported variants from 2021 to 2022 in China, reflecting the higher diversity of lineages in the second half of 2022, and revealed the predominant lineages of countries or regions that are in close contacts to China, providing new insights into the global prevalence of SARS-CoV-2.