Archives of Virology最新文献

We recently discovered a novel member of the family Arteriviridae, hedgehog arterivirus 1 (HhAV-1), in the brains of hedgehogs with fatal encephalitis. In this study, we classified this virus and investigated its intrahost genomic diversity using next-generation sequencing. We sequenced HhAV-1 genomes from specimens from seven hedgehogs (two males and five females) with signs of encephalitis that were collected in Buckinghamshire, Gloucestershire, and Cambridgeshire, England, and had died or been euthanised between 2013 and 2024. Analysis of the intrahost populations of these seven HhAV-1 isolates and a previously described isolate revealed the presence of single-nucleotide polymorphisms (SNPs), which were most frequent in open reading frames 5, 6, and 7, encoding glycoprotein 5, the membrane protein, and the nucleocapsid protein. Pairwise comparisons of the eight HhAV-1 variants showed that the nucleotide sequence identity values in their combined complete coding sequences ranged from 76.2% to 100%. The eight HhAV-1 variants also shared at least 82.8% amino acid sequence identity in five domains that are involved in replication and are used for the classification of nidoviruses: 3CLpro, NiRAN, RdRp, ZBD, and HEL1. In a replicase-based phylogenetic tree of members of the family Arteriviridae, the HhAV-1 variants formed a sister cluster to African pouched rat arterivirus. A DEmARC-based pairwise distance analysis indicated that these viruses may comprise a new species, for which we propose the name "Xiarterivirus erinaceid", in a new genus in the subfamily Heroarterivirinae.

The full genome sequence of a positive-sense (+) single-stranded (ss) RNA virus, which we have named "Neopestalotiopsis nebuloides deltaflexivirus 1" (NnDFV1), from Neopestalotiopsis nebuloides strain N-7 was sequenced and analyzed. The NnDFV1 genome is 7,719 nucleotides in length with a GC content of 49%, excluding the poly(A) tail, and contains a large open reading frame (ORF1) and three smaller ORFs (2–4). ORF1 encodes a replication-associated polyprotein (RP) consisting of three conserved domains: viral methyltransferase (Mtr), viral helicase (Hel), and RNA-dependent RNA polymerase (RdRp), whereas ORFs 2–4 encode three hypothetical proteins (18–20 kDa). Phylogenetic analysis showed that NnDFV1 formed a distinct clade together with Pestalotiopsis deltaflexivirus 1 (PDFV1), which is a new member of the genus Deltaflexivirus within the family Deltaflexiviridae. This is the first report of a novel deltaflexivirus found in the phytopathogenic fungus Neopestalotiopsis nebuloides.

Dengue is an arboviral disease caused by dengue virus, which is mostly found in tropical regions, and the number of human cases has increased dramatically since 2000, with 5.2 million cases reported in 2019, according to WHO reports, 70% of which were in Southeast Asia, the Western Pacific, and Asia. Dengue infection can result in a wide range of clinical manifestations, ranging from fever to severe dengue shock syndrome, which can be fatal, particularly in those with secondary dengue. This review of the aetiology of dengue fever examines the complex interactions between the virus and the immune system and the interaction between viral and host factors and also covers outbreaks, the severity of disease caused by different serotypes, and methods for diagnosis of dengue, such as serological tests, nucleic acid amplification tests, and ELISA assays for detecting the NS1 antigen. Current treatment options and prevention strategies, including vector control measures, environmental interventions, and insect repellents are also discussed. This review highlights the challenges involved in developing a dengue vaccine, which is complicated by the need for an efficient and balanced immune response against all genotypes of the four serotypes.

Bacteria of the genus Glutamicibacter, due to their ubiquity, nutritional versatility, and ability to adapt to environmental stresses, play an important role in natural ecosystems and have been extensively studied. Nevertheless, there remains a significant gap in our knowledge regarding Glutamicibacter phages, particularly in comparison to those of the related actinobacteria. To date, only two virulent phages infecting G. arilaitensis have been described. To our knowledge, this is the first report on the isolation, characterization, and genome analysis of a temperate phage targeting G. halophytocola, an endophytic bacterium known for its plant-growth-promoting effect. The phage Ph-p5, with siphovirus structure, was isolated from soil. It exhibited a long latent period (120 min), a moderate burst size (87 ± 3 PFU/infected cell), and stability over a wide range of pH and temperature. The circularly permuted linear double-stranded DNA genome of phage Ph-p5, comprising 43,694 bp with a G + C content of 57.1%, contains 65 putative protein-coding sequences and one sequence encoding tRNA. Of the identified open reading frames, 33 were of unknown function, while the remaining ones were grouped into functional modules, including structural proteins, DNA replication and regulation, lysogeny, and lysis. The presence of intact lysogeny-related genes, together with the capacity for lysogenisation of the host strain G. halophytocola BIM B-1594, provides evidence that Ph-p5 is a temperate phage. Phylogenetic analysis demonstrated that phage Ph-p5 belongs to the class Caudoviricetes but exhibits significant divergence from known phages and may be assigned to a new genus, for which we propose the name “Petuglutavirus”.

We isolated and characterized the novel polyvalent T-even type bacteriophage vB_SenS_Jbel from wastewater using an enrichment of three different Salmonella strains. The vB_SenS_Jbel virions have prolate icosahedral capsids approximately 100 nm long and 80 nm wide. The genome consists of linear, double-stranded DNA that is 165,566 bp long. Analysis of the genome and structure of vB_SenS_Jbel indicates that it belongs to the genus Tequatrovirus of the family Straboviridae. This novel polyvalent phage can infect Escherichia coli and multiple Salmonella and Shigella species through its unique tail fiber structure.

An unusually large number of human parvovirus B19 (B19V) infections were reported in European countries in 2023/2024, but the genetic background of this B19V epidemic strain is unknown. In this study, there was a larger number of confirmed B19V infections (five in 2021, eight in 2023, and 59 in 2024) and higher IgG seroprevalence (41.4% in 2022 and 54.3% in 2024) in Transdanubia, Hungary, in 2024 compared to 2018-2023. A B19V genotype 1a2 variant (prototype, 1338/HUN/2024, PQ155933) with common and unique nucleotide insertions in the untranslated regions of the genome and nonsynonymous and synonymous mutations in the coding region (NS1 and VP1) could be responsible to the ongoing B19V epidemic in Europe.

The whole-genome sequences of orthobunyaviruses isolated from cattle reared on Yonaguni Island (the western-most point of Japan's territory) were determined. The sequences of their S and L RNA segments were observed to be almost identical to those of Shamonda virus (SHAV) isolates identified in Japan, whereas the sequences of their M RNA segments were very similar to those of Japanese isolates of Sathuperi virus (SATV). Our findings indicate that the two novel isolates are natural reassortants between SHAV and SATV, which share a genome segment organization similar to that of Schmallenberg virus. The nucleotide sequence of the 5' non-coding region of the novel isolates differs from those of previously sequenced SATV isolates, suggesting that the M RNA segments of the reassortants were not derived from SATV strains that were detected recently in Japan.

Passion fruit woodiness disease (PWD), caused by cowpea aphid-borne mosaic virus (CABMV), severely damages leaves and fruits, compromising passion fruit production. The dynamics of this infection in Passiflora spp. are still poorly understood. The objective of this study was to determine the systemic infection time of CABMV in Passiflora spp. and to quantify the viral titer throughout the infection. Plants of Passiflora edulis Sims. (BGP418, susceptible), P. cincinnata Mast. (BGP243, moderately resistant), P. setacea DC. (BRS Pérola do Cerrado, resistant), and P. suberosa L. (BGP152, resistant) were used. The study was conducted in a climate chamber, and mechanical inoculations were carried out on the first pair of basal leaves of the seedlings. Symptoms were assessed using a scale whose scores were converted into a disease index (DI%), and the viral titer was determined at different time points by real-time quantitative RT-PCR (RT-qPCR). The first symptoms of the virus were observed at seven days after inoculation (Dai) in P. edulis (DI = 5.15%) and at 10 Dai in P. cincinnata (DI = 8.86%). On the other hand, P. setacea and P. suberosa did not show typical symptoms of the disease (DI = 0.00%). Systemic CABMV infection was detected at 30 minutes after inoculation regardless of the level of resistance of the Passiflora species. There was an increase in viral titer with infection time with P. edulis and P. cincinnata, although in the case of P. edulis, the increase in CABMV titer occurred earlier, at 2 Dai, and in P. cincinnata at 8 Dai. In the asymptomatic species (P. setacea and P. suberosa), there was no variation in the viral titer over the time periods evaluated. This pioneering study provides information for the selection of time intervals for future molecular research into the interaction between Passiflora spp. and CABMV.

The aim of this study was to detect chicken parvovirus (ChPV) and turkey parvovirus (TuPV) on Turkish poultry farms and examine the molecular epidemiology of these viruses. In 2023, a total of 1,060 fecal samples were collected from 76 broiler farms and 30 turkey farms across various regions of Turkiye. The overall positivity rate was 72.3% (55/76) in broiler flocks and 70% (21/30) in turkey flocks. Among these, the positivity rate was 35% (7/20) in birds showing no signs of enteritis. The findings of this study suggest that, depending on the genetic variability of regional strains or the viral load, nested-PCR-based methods may prove more effective than single-step PCR for detecting ChPV and TuPV cases. Therefore, it is recommended to incorporate nested PCR in molecular epidemiological studies to minimize the risk of overlooking positive cases. Phylogenetic analysis of the VP1, VP2, and complete genome sequences of TUR/2023/ChPV and TR/2023/TuPV revealed that both strains clustered with American strains in distinct lineages. Analysis using the recombination detection programs RDP4.0 and SimPlot 3.5.1 strongly suggested that TUR/2023/ChPV may be a recombinant of strains from China and Brazil. Despite the observed genetic variability in the VP2 protein, an examination of B-cell epitopes showed a high degree of similarity between ChPV and TuPV strains. This study represents the first documentation of the emergence and prevalence of TuPVs in Turkiye, providing complete genome sequences for both ChPV and TuPV. Given the high prevalence and genetic diversity of these viruses and their presence in clinically asymptomatic birds, it is crucial for stakeholders in the poultry industry to implement regular flock screenings for these and similar viral pathogens. Proactive measures like these are essential for mitigating the economic impact of these important pathogens and developing effective preventive strategies.

Seadornavirus is a genus of mosquito-borne viruses that includes Banna virus, which was first discovered in human patients with encephalitis and fever, as well as Kadipiro virus and Liao ning virus. In this study, we used metagenomics to investigate the diversity of viruses in wild ducks and detected both Banna virus and Kadipiro virus in wild birds in Siberia. These data suggest that seadornaviruses, which were previously only found in South East Asia, are also circulating in Northern Eurasia.