VirusDisease最新文献

The seroepidemiological characteristics of the SARS-CoV-2 were investigated along with the secondary infection rate in the household of confirmed patients in a high-risk population in Mashhad, Iran. The current descriptive cross-sectional study includes a total of 154 confirmed cases of SARS-CoV-2 infection in Mashhad, Iran, from March 2021 to December 2021. The participants' families were screened for SARS-CoV-2 secondary infection rate, and a standard checklist containing the research parameters was completed by all participants. The participants' average age was 43.19 ± 9.86 years, of which 80 (51.9%) were female and the rest were male. Of the participants, 147 (95.5%) reported using face masks, and 83 (53.9%) were using masks all the time. IgG and IgM of COVID-19 were positive in 43 (27.9%) and 8 (5.2%) individuals, respectively. The average positive rate in the participants was 0.12 ± 0.24. Wearing masks when contracting with an infected patient (p < 0.001 and r = -0.370), using a separate room (p < 0.001 and r = -0.663), a separate toilet (p < 0.001 and r = -0.663) and the number of family members (p = 0.013 and r = 0.201) were significantly correlated to the positive rate of infection among the participants. Adherence to wearing masks and using separate rooms, and toilets by households in contact with a COVID-19-confirmed patient reduces the secondary transmission rate of the disease among healthy family members. In addition, the probability of COVID-19 transmission is higher in larger families.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-024-00903-9.

Animal studies indicated that human papillomavirus (HPV) transgenic mice develop cataract. Viral infections have been proposed as a potential contributing factor of cataract. This study aimed to examine the association between HPV infection and the risk of developing cataract. We enrolled 224,203 individuals diagnosed with HPV infection between January 1, 2000, and December 31, 2018, from the National Health Insurance Research Database of Taiwan. Propensity-score matching at a 1:1 ratio was conducted to obtain an HPV cohort and a matched non-HPV cohort. We used a Cox proportional hazards regression model to estimate the hazard ratio and 95% confidence interval. The adjusted hazard ratio for developing cataract was 1.36 (95% confidence interval, 1.32-1.39; p < 0.001) in the HPV cohort, and the risk of developing cataract was age-dependent. Females were found to have a higher risk than males. The use of ophthalmic steroids was associated with an elevated risk of cataract formation. Multivariate analysis further highlighted a significant increase in cataract risk within the HPV cohort. Robust sensitivity analyses confirmed that the cumulative risk of cataract was substantially higher in the HPV cohort than in the non-HPV cohort over a 17-year follow-up period (log-rank test, p < 0.001). The use of chlorpromazine was associated with a lower risk of cataract development. However, a significant risk of cataract was observed in HPV patients concurrently treated with chlorpromazine (adjusted hazard ratio, 4.94; 95% confidence interval, 1.82-13.44; p = 0.017). This nationwide cohort study showed that HPV infections are associated with an increased risk of cataract development.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-024-00907-5.

Small ruminants contribute significantly to the animal husbandry economy. Peste des petits ruminants (PPR) is one of the major infectious diseases of small ruminants caused by small ruminant morbillivirus (SRMV) previously known as PPR virus-PPRV, a member of the genus Morbillivirus, which causes significant morbidity and mortality in affected population thereby disturb the economy of rural poor. The present study describes the molecular characterization and phylogenetic analysis of SRMV with complete nucleocapsid (N) and fusion (F) gene sequence. Phylogenetic analysis of the SRMV isolates revealed that, all the isolates shared a common ancestor with Tamil Nadu isolate and were grouped under lineage IV. Phylogenetic analysis also revealed that two genetic groups are circulating in Kerala and have recently evolved. Analysis of the F protein of SRMV showed two unique mutations (A18E and S430I) in Kerala isolates. Amino acid analysis of nucleoprotein revealed that most of the changes were in the C-C-terminal region. Four unique mutations were also observed in the nucleoprotein (NP) of the present SRMV isolates (I153V, A431V, R458M, and G461K). Among the 19 B cell epitopes identified on nucleoprotein, at least one amino acid variation was detected in four epitopes. These changes may affect the monoclonal antibody-based diagnostic assays. These changes in the F and N genes indicate the continuous emergence and circulation of new variants of the virus within the same geographical area. This is the first report on the molecular characterization of PPRV isolates based on full N and F genes from the Kerala state of India.

Avian infectious bronchitis virus (IBV) belongs to family Coronaviridae, genus Gammacoronavirus and is one of the most predominant causes of respiratory disease in poultry. Its high mutation rate constantly leads to the emergence of novel variants that complicate disease control. In 2016, a GA13-like IBV outbreak occurred in Costa Rica, prompting the introduction of the 4/91 live-attenuated vaccine. The objective of this research was to perform a molecular characterization of IBV variants circulating in the country six years after the introduction of the 4/91 vaccine. A total of 177 samples from symptomatic birds were analyzed, with 43 testing positive for IBV. Seven complete S1 sequences were obtained and clustered within the GI-13 lineage by phylogenetic analysis. Sequence analysis showed high genetic similarity to the 4/91 vaccine strain, with nucleotide and amino acid sequence identities over 99.13% and 97.96%, respectively, despite these samples being taken from unvaccinated birds. Post-translational modification analysis of the S1 protein revealed conserved N-glycosylation and palmitoylation sites, while two serine phosphorylation changes were predicted between the obtained sequences and the vaccine strain. Selective pressure analysis identified 10 sites under positive selection, mainly located within the receptor-binding domain and hypervariable regions of the S1 subunit. The presence of 4/91-like variants in unvaccinated birds needs attention, and its relation to observed pathology requires further research. Continuous surveillance is essential to monitor for potential vaccine escape mutants and mitigate their impact.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-025-00910-4.

The RNA silencing mechanism is a crucial regulatory system in plants, particularly in antiviral defense. However, most of the plant viruses encode a specific protein called RNA silencing suppressor protein that suppress the RNA silencing mechanism of host. This study employs the bioinformatics tools, including SWISS homology model and I-TASSER, to predict the coat protein (CP) tertiary structure of Indian citrus ringspot virus (ICRSV). Then, five protein-protein docking servers (GRAMM, pyDockWEB, HawkDock, ZDOCK and ClusPro) were utilized to investigate interactions of CP of ICRSV with Argonaut2/Dicer-Like (DCL4) protein 4 of RNA silencing pathway of host. In blind docking experiments, the CP consistently engaged in docking interactions with DCL4, while with AGO2, it interacted near the PIWI and MID domains. The AGO2-CP cluster demonstrated 4 salt bridges, 30 hydrogen bonds, and 328 non-bonded contacts, with interface areas spanning 2529 in AGO2 and 2424 in CP, involving 50 and 51 interface residues, respectively. Similarly, the DCL4-CP cluster showed 5 hydrogen bonds and 122 non-bonded contacts, with interface areas spanning 965 in DCL4 and 987 in CP, involving 16 and 19 interface residues, respectively. The established phenomenon of CP interaction with AGO2/DCL4, may resulting in the inhibition of the RNA silencing mechanism and shedding light on the suppression mechanisms of host defense responses.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-024-00904-8.

Newcastle disease virus (NDV) is an avian paramyxovirus known to infect more than 250 bird species across the globe. NDV is enveloped and carries a negative-sense RNA genome that codes for six structural proteins and two accessory proteins expressed through a unique co-transcriptional RNA editing mechanism. One of the accessory viral proteins, V protein, is multifunctional and a well-known interferon (IFN) antagonist. The overexpression of V protein is known to enhance viral production kinetics during NDV infection. In this study, we elucidated the events that lead to this augmented viral replication. The V protein overexpression downregulated the expression of host RNA sensor, namely MDA5. Furthermore, during the over-expression of V protein in NDV infected cells, the V protein aggregated in the perinuclear region, co-localizing and binding with the replicating dsRNA. Our structural studies and in silico predictions suggest that V protein binding with dsRNA interferes and competes with MDA5 for binding to dsRNA, eventually disrupting the IFN induction and facilitating the viral replication. This study reports a novel mechanism of host immune evasion by the accessory V protein.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-024-00908-4.

Monkeypox virus (MPV/MPXV/hMPXV) is a zoonotic infection that is a causative agent of monkeypox disease, which is mainly endemic in West and Central Africa regions, but recent trends suggested that the virus is transmitted around 116 countries worldwide and is still spreading in multiple non-endemic countries, causing global outbreaks. The current therapeutic options for Mpox are limited, with the WHO temporarily recommending smallpox drugs. This suggests an urgent need to discover new therapeutics that may target both viral and host markers involved in the virus life cycle. Curcumin, a polyphenolic natural compound, has broad-spectrum pharmacological activity in both DNA and RNA viruses. Therefore, this study was planned to evaluate the antiviral properties of curcumin against MPXV proteins as well as induced host targets using computational approaches, such as gene target identification, PPI network analysis, antiviral activity prediction, and molecular docking. Our network pharmacology and docking results demonstrated that curcumin majorly targets Mpox DNA polymerase holoenzyme, Methyltransferase VP39, A42R profilin-like protein, envelope protein E8, and TNF, MAPK, NFKB1, and PTGS2 to regulate host inflammatory pathways such as TNF, NF-κB, and MAPK signaling during Mpox infection. Further, we found that curcumin has a strong binding affinity toward the DNA polymerase of MPXV compared to Cidofovir, an approved inhibitor of DNA polymerase. Collectively, our findings suggested that curcumin may have potential use as a multi-targeted antiviral agent against emerging Mpox, encouraging future research that provides the molecular basis for exploring the role of curcumin as a broad-spectrum antiviral agent during viral outbreaks.

Graphical abstract: The ligand binding site of MPXV DNA polymerase shows the molecular interactions with curcumin and amino acids present on the active site of the protein.

Seed transmission (ST) plays an important role in virus dispersion and disease epidemiology. Many viruses infecting cowpea are known to be seed-transmitted. This study evaluated the rate of virus ST in cowpea varieties inoculated under screenhouse conditions (SC) with bean common mosaic virus-blackeye cowpea mosaic strain (BCMV-BlCM), Southern bean mosaic virus (SBMV) and cucumber mosaic virus (CMV) under single and multiple-infections. Up to 50 seeds harvested from the virus-infected plants of each variety per treatment were used for the grow-out test under insect-proof SC. Data were recorded on seed germination (SG), symptoms in seedlings, and virus ST. The leaf samples were tested for viruses by enzyme-linked immunosorbent assay (ELISA) and reverse-transcription polymerase chain reaction (RT-PCR). The SG rate was 78 ± 2.8-100 ± 0% in all treatments. A total of 1.5% of 1,604 seedlings infected singly showed symptoms, whereas in diagnostics testing, viruses were detected in 2.6% of plants, indicating occurrence of asymptomatic ST. The highest rate of transmission observed for single infections was 17% CMV in IT98K-133-1-1, 17.1% BCMV-BlCM in IT98K-503-1, and 2.3% SBMV in IT99K-1060. The highest CMV frequency under coinfection was 22.2% in plants inoculated (PI) with SBMV + CMV, 4.2% for BCMV-BlCM in PI with BCMV-BlCM + CMV and 2.3% for SBMV in PI with BCMV-BlCM + SBMV + CMV. This study indicated high variation in the rates of ST based on cultivar and virus type, and for each virus under mixed-infection conditions. Diagnostic confirmation detected a higher percentage of seed-transmitted viruses compared to visual assessment, warranting the need for diagnostics for the reliable detection of seed-transmitted viruses.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-024-00899-2.

The COVID-19 pandemic originated in Wuhan in 2019 due to a novel SARS-COV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) responsible for the massive number of deaths across the globe. So far, several vaccines have been developed using highly antigenic Spike protein and authorized for emergency use, reducing the severity of the infection. Nonetheless, the virus continues to evolve through multiple mutations, resulting in numerous variants with enhanced transmission that evade the vaccine-induced immune response. Given the persistently mutating nature of the SARS-COV-2 virus, peptide-based vaccines with highly conserved epitopes may offer lasting protection against evolving variants. This study presents an immunoinformatics-based identification of potentially immunogenic CD8 + T-cell epitopes (CTLs) of Spike (S), Membrane (M), Nucleocapsid (N) and Envelope (E) proteins of SARS-COV-2. By utilizing the immunoinformatic approach, 21 epitopes have successfully been evaluated, where 15, 3, 2, and 1 epitopes are respectively from Spike, Membrane, Envelope and Nucleocapsid proteins. Out of these, 20 are found to be identical with experimentally verified immunogenic epitopes, except for the novel NTQEVFAQV epitope from spike protein. These epitopes show a high degree of conservation in both former variants of concerns (VOCs), variants of interest (VOIs) and current variants under monitoring (VUMs), are non-toxic, non-homologous to humans and have a wide range of global population coverage. Furthermore, utilizing molecular docking analysis followed by molecular dynamics simulation, these epitopes have been verified as having stable interactions with their respective HLA molecules. The described framework and projected immunogenic epitopes could significantly impact the development of SARS-COV-2 vaccines based on peptides.

Supplementary information: The online version contains supplementary material available at 10.1007/s13337-024-00894-7.

Banana bunchy top virus (BBTV) is the most destructive viral disease of banana crop in the Philippines. The disease causes heavy damage to important local varieties, 'Lakatan' and 'Cavendish'. Infected planting materials can cause long-term disease transmission causing geographical location to dictate genetic variation among viral strains. Hence, there is a need for an efficient and reliable quarantine detection procedure. This study developed a high-throughput real-time PCR protocol for batch detection of BBTV. A primer set derived from the DNA-R region of the virus was designed for specific BBTV detection. Tests for optimal annealing temperature, sample load, and sensitivity were performed. Finally, the cost per sample was compared to conventional end-point PCR. Optimization of the annealing temperature, from 55.5 ℃ to 63.5 ℃, yielded virus detection. The detection protocol developed was efficient to detect BBTV from a leaf disc measuring up to 5 mm diameter and weight of approximately 3 mg. DNA from infected leaf discs was detectable up to 1:10000 dilution. Sample pooling was detectable up to 1:99 infected to healthy leaf disc ratio. This sensitive and cost-efficient batch detection method for BBTV detection will be useful for quarantine services and various diagnostic applications.