Avian orthoreovirus (ARV) is an important pathogen associated with viral arthritis in chickens and causes substantial economic losses in the poultry industry. In recent years, ARVs belonging to clusters 2 and 6, which have rarely been reported in Japan, have been isolated from broiler chickens derived from breeder flocks vaccinated with the ARV vaccine strains 1733 and 2408. In this study, whole-genome sequencing and phylogenetic analyses were performed on ARV isolates circulating in Japan to clarify their genetic differences from the vaccine strains. Comparative analyses revealed considerable genomic diversity even among virus strains isolated from the same geographic region, suggesting frequent genetic reassortment among circulating ARVs. None of the genomic segments of our isolates showed high-sequence identity to the currently used vaccine strains. In particular, the σC protein showed low amino acid identities (49.39–56.48
Enterovirus 71 (EV71) is a major causative agent of hand, foot, and mouth disease (HFMD) and is associated with severe neurological complications in young children. However, effective antiviral therapeutics remain limited. In this study, nanoparticles derived from Polygonum cuspidatum (NPC) were prepared and their antiviral activity against EV71 was evaluated in vitro and in vivo. Cytotoxicity and antiviral assays in human rhabdomyosarcoma (RD) cells demonstrated that NPC exhibited substantially lower cytotoxicity than the crude extract while maintaining comparable antiviral potency against EV71. NPC treatment markedly reduced EV71-induced cytopathic effects and significantly decreased viral RNA levels, as confirmed by indirect immunofluorescence and RT-qPCR. In an EV71-infected ICR suckling mouse model, oral administration of NPC significantly improved survival, attenuated clinical disease scores and body weight loss, and reduced viral loads in muscle and brain tissues in a dose-dependent manner. Histopathological analysis revealed alleviated tissue injury in the NPC-treated mice. These findings suggest that nanonization improves the therapeutic index of P. cuspidatum and support further investigation of NPC as a potential plant-derived antiviral candidate for EV71 infection.
Irkut virus (IRKV) is a member of genus Lyssavirus, which leads to fatal encephalitis in humans and is primarily found in bats and dogs that transmit the virus to humans via bites/saliva. Most cases have been reported in Russia and in Siberia and recently in China. Whole genome sequencing has shown a number of codon changes in antigenic sites common to the Rabies vaccine reducing cross-protection, which makes IRKV a serious public health threat because of its high fatality. In this study, a multi-epitope vaccine against the IRKV glycoprotein was designed via reverse vaccinology approach. Seven B-cell, seven MHC-I, and seven MHC-II epitopes were selected. These epitopes have predicted HLA binding affinity and are non-allergen, and 12 out of 21 epitopes were fully conserved across the three circulating IRKV strains, whereas remaining nine carried out one or two substitutions. The chosen epitopes covered 99.57
Getah virus (GETV) is a mosquito-borne alphavirus (family Togaviridae) that poses a significant threat to the swine industry by causing reproductive disorders in sows and neurological symptoms in piglets. In this study, a GETV strain, designated HN-2025, was isolated from a commercial pig farm in Hunan Province, China, during a clinical outbreak. The isolate induced typical cytopathic effects (CPE) in BHK-21 cells, including cell rounding, shrinkage, and detachment. The complete genome of HN-2025 was determined to be 11,689 nucleotides (nt) in length and exhibited the canonical genomic organization of GETV: 5’ untranslated region (UTR), nonstructural proteins (nsP1-nsP4), structural proteins (C, E3, E2, 6 K, E1), and 3’ UTR. Sequence homology analysis revealed that HN-2025 shared the highest nucleotide identity (98.6
Zucchini yellow mosaic virus (ZYMV) is a major pathogen that negatively affects cucurbit crops. To elucidate the molecular characteristics and evolutionary dynamics of ZYMV in China, ZYMV was isolated from Cucurbita and Luffa samples collected from plants exhibiting typical yellow mosaic symptoms in Tai’an, Shandong Province, and its complete genome sequence was determined. Using reverse transcription PCR combined with rapid amplification of cDNA ends, the full-length genome sequences of two isolates obtained from Luffa and Cucurbita (ZYMV-sg, GenBank accession no. PV007922; ZYMV-ng, GenBank accession no. PV007923) were determined. Both genomes were 9,592 nt in length (excluding the poly(A) tail). The genomes encoded a polyprotein of 3,080 amino acids and exhibited a genomic organization typical of members of the family Potyviridae. Phylogenetic analysis revealed that both isolates were most closely related to Chinese isolates and formed a distinct subclade within the major group B-I. Recombination analysis identified specific recombination events in ZYMV-ng, indicating that genetic recombination contributed to the molecular evolution of ZYMV. Further analyses suggested that purifying selection played a dominant role in shaping ZYMV evolution. These findings provide important molecular insights into the genomic structure, phylogenetic relationships, and sequence evolution of ZYMV isolates from Cucurbita and Luffa in China and provide a basis for further research on virus–host interactions and the development of targeted disease control strategies.
