SARS-CoV-2 has been responsible for the recent pandemic all over the world, which has caused many complications. One of the hallmarks of SARS-CoV-2 infection is an induced immune dysregulation, in some cases resulting in cytokine storm syndrome, acute respiratory distress syndrome and many organs such as lungs, brain, and heart that are affected during the SARS-CoV-2 infection. Several physiological parameters are altered as a result of infection and cytokine storm. Among them, microRNAs (miRNAs) might reflect this poor condition since they play a significant role in immune cellular performance including inflammatory responses. Both host and viral-encoded miRNAs are crucial for the successful infection of SARS-CoV-2. For instance, dysregulation of miRNAs that modulate multiple genes expressed in COVID-19 patients with comorbidities (e.g., type 2 diabetes, and cerebrovascular disorders) could affect the severity of the disease. Therefore, altered expression levels of circulating miRNAs might be helpful to diagnose this illness and forecast whether a COVID-19 patient could develop a severe state of the disease. Moreover, a number of miRNAs could inhibit the expression of proteins, such as ACE2, TMPRSS2, spike, and Nsp12, involved in the life cycle of SARS-CoV-2. Accordingly, miRNAs represent potential biomarkers and therapeutic targets for this devastating viral disease. In the current study, we investigated modifications in miRNA expression and their influence on COVID-19 disease recovery, which may be employed as a therapy strategy to minimize COVID-19-related disorders.

Coxsackievirus A16 (CV-A16) is still an important pathogen that causes hand, foot and mouth disease (HFMD) in young children and infants worldwide. Previous studies indicated that CV-A16 infection is usually mild or self-limiting, but it was also found that CV-A16 infection can trigger severe neurological complications and even death. However, there are currently no vaccines or antiviral compounds available to either prevent or treat CV-A16 infection. Therefore, investigation of the virus‒host interaction and identification of host proteins that play a crucial regulatory role in the pathogenesis of CV-A16 infection may provide a novel strategy to develop antiviral drugs. Here, to increase our understanding of the interaction of CV-A16 with the host cell, we analyzed changes in the proteome of 16HBE cells in response to CV-A16 using tandem mass tag (TMT) in combination with LC‒MS/MS. There were 6615 proteins quantified, and 172 proteins showed a significant alteration during CV-A16 infection. These differentially regulated proteins were involved in fundamental biological processes and signaling pathways, including metabolic processes, cytokine‒cytokine receptor interactions, B-cell receptor signaling pathways, and neuroactive ligand‒receptor interactions. Further bioinformatics analysis revealed the characteristics of the protein domains and subcellular localization of these differentially expressed proteins. Then, to validate the proteomics data, 3 randomly selected proteins exhibited consistent changes in protein expression with the TMT results using Western blotting and immunofluorescence methods. Finally, among these differentially regulated proteins, we primarily focused on HMGB1 based on its potential effects on viral replication and virus infection-induced inflammatory responses. It was demonstrated that overexpression of HMGB1 could decrease viral replication and upregulate the release of inflammatory cytokines, but deletion of HMGB1 increased viral replication and downregulated the release of inflammatory cytokines. In conclusion, the results from this study have helped further elucidate the potential molecular pathogenesis of CV-A16 based on numerous protein changes and the functions of HMGB1 Found to be involved in the processes of viral replication and inflammatory response, which may facilitate the development of new antiviral therapies as well as innovative diagnostic methods.

BACKGROUND: Epstein-Barr virus (EBV) infection is a major global threat; its manifestations range from the absence of symptoms to multiorgan malignancies and various gastrointestinal diseases. Analyzing the composition and metabolomic profile of gut microbiota during acute EBV infection might be instrumental in understanding and controlling EBV. METHODS: Six tree shrews were inoculated with EBV by intravenous injection. Blood was collected at regular intervals thereafter from the femoral vein to detect EBV and inflammatory biomarker. At the same time, tree shrew faeces were collected for 16 S rRNA gene sequencing and Non-targeted metabolomics analysis. RESULTS: 16 S rRNA gene characterization along with β diversity analysis exhibited remarkable alterations in gut microflora structure with a peak at 7 days post-infection(dpi). Some alterations in the relative richness of bacterial taxon were linked to infectious indicators. Of note, Butyricicoccus relative richness was positively linked to EBV presence in the blood and plasma, the opposite correlation was seen with Variovorax and Paramuribaculum. Non-targeted metabolomics indicated the fecal metabolome profile altered during EBV infection, particularly 7 dpi. The relative abundance of geranic acid and undecylenic acid in stool samples was positively linked to systemic inflammatory biomarkers, and an inverse relationship was reported with the estrone glucuronide, linoleic acid, protoporphyrin IX and tyramine. CONCLUSION: Collectively, EBV infection in this model correlated with changes in the composition and metabolome profile of the gut microbiota.

SARS-CoV-2 is a zoonotic betacoronavirus that was first reported at the dawn of 2019 in Wuhan, China and has since spread globally, causing an ongoing pandemic. Anthroponotic transmission was reported early, with confirmed infections reported in 26 species to date, including dogs and cats. However, there is a paucity of reports on the transmission of SARS-CoV-2 to companion animals, and thus, we aimed to estimate the seroprevalence of SARS-CoV-2 in dogs and cats in Sarawak, Malaysia. From August 2022 to 2023, we screened plasma samples of 172 companion animals in Sarawak, Malaysia, using a species-independent surrogate virus neutralization test. Our findings revealed the presence of neutralizing antibodies of SARS-CoV-2 in 24.5% (27/110) of dogs and 24.2% (15/62) of cats. To the best of our knowledge, this is the first report of the seroprevalence of SARS-CoV-2 in companion animals in Malaysia. Our findings emphasize the need for pet owners to distance themselves from their pets when unwell, and a strategy must be in place to monitor SARS-CoV-2 in companion animals to assess the potential impact of the virus on companion animals.

BACKGROUND: The interaction between bacteriophages and their hosts is intricate and highly specific. Receptor-binding proteins (RBPs) of phages such as tail fibers and tailspikes initiate the infection process. These RBPs bind to diverse outer membrane structures, including the O-antigen, which is a serogroup-specific sugar-based component of the outer lipopolysaccharide layer of Gram-negative bacteria. Among the most virulent Escherichia coli strains is the Shiga toxin-producing E. coli (STEC) pathotype dominated by a subset of O-antigen serogroups. METHODS: Extensive phylogenetic and structural analyses were used to identify and validate specificity correlations between phage RBP subtypes and STEC O-antigen serogroups, relying on the principle of horizontal gene transfer as main driver for RBP evolution. RESULTS: We identified O-antigen specific RBP subtypes for seven out of nine most prevalent STEC serogroups (O26, O45, O103, O104, O111, O145 and O157) and seven additional E. coli serogroups (O2, O8, O16, O18, 4s/O22, O77 and O78). Eight phage genera (Gamaleya-, Justusliebig-, Kaguna-, Kayfuna-, Kutter-, Lederberg-, Nouzilly- and Uetakeviruses) emerged for their high proportion of serogroup-specific RBPs. Additionally, we reveal sequence motifs in the RBP region, potentially serving as recombination hotspots between lytic phages. CONCLUSION: The results contribute to a better understanding of mosaicism of phage RBPs, but also demonstrate a method to identify and validate new RBP subtypes for current and future emerging serogroups.

BACKGROUND: Saffold virus (SAFV), which belongs to the genus Cardiovirus of the family Picornaviridae, is associated with acute respiratory or gastrointestinal illnesses in children; it is also suspected to cause severe diseases, such as acute flaccid paralysis and aseptic meningitis. However, the understanding of the mechanism of its pathogenicity is still limited due to the many unknowns about its lifecycle; for example, the cellular receptor for its infection remains to be determined. A system to monitor SAFV infection in vitro and in vivo is required in order to accelerate research on SAFV. RESULTS: We generated a recombinant SAFV expressing green fluorescent protein (GFP) or UnaG, a novel fluorescent protein derived from Japanese eel. HeLa cells infected by either GFP or UnaG-expressing SAFV showed a bright green fluorescent signal, enabling convenient monitoring of SAFV infection. However, the expression of GFP but not UnaG was quickly lost during virus passaging due to the difference in genetic stability in the SAFV virus genome; the UnaG gene was stably maintained in the virus genome after at least five passages. CONCLUSIONS: SAFV infection of cultured cells can easily be monitored using UnaG-expressing SAFV, which is superior to GFP in terms of genetic stability in the virus genome. This virus could be a useful tool for SAFV research, such as comparing the susceptibility of various cells to SAFV infection and evaluating the effects of antivirals on SAFV infection in high-throughput screening.

BACKGROUND: Several anti-retroviral drugs are available against Human immunodeficiency virus type-1, but have multiple adverse side effects. Hence, there is an incessant compulsion for effectual anti-retroviral agents with minimal or no intricacy. Traditionally, natural products have been the most successful source for the development of new medications. Withania somnifera, also known as Ashwagandha, is the utmost treasured medicinal plant used in Ayurveda, which holds the potential to give adaptogenic, immunomodulatory, and antiviral effects. However, its effect on HIV-1 replication at the cellular level has never been explored. Herein, we focused on the anti-HIV-1 activity and the probable mechanism of action of hydroalcoholic and aqueous extracts of Withania somnifera roots and its phytomolecules. METHODS: The cytotoxicity of the extracts was determined through MTT assay, while the in vitro anti-HIV-1 activity was assessed in TZM-bl cells against the HIV-1 strains of X4 and R5 subtypes. Results were confirmed in peripheral blood mononuclear cells, using the HIV-1 p24 antigen assay. Additionally, the mechanism of action was determined through the Time of Addition assay, which was further validated through the series of enzymatic assays, i.e. HIV-1 Integrase, Reverse transcriptase, and Protease assays. To explore the role of the identified active metabolites of Withania somnifera in antiretroviral activity, molecular docking analyses were performed against these key HIV-1 replication enzymes. RESULTS: The hydroalcoholic and aqueous extracts of Withania somnifera roots were found to be safer at the sub-cytotoxic concentrations and exhibited their ability to inhibit replication of two primary isolates of HIV-1 through cell-associated and cell-free assays, in dose-dependent kinetics. Several active phytomolecules found in Withania somnifera successfully established hydrogens bonds in the active binding pocket site residues responsible for the catalytic activity of HIV replication and therefore, signifying their role in the attenuation of HIV-1 infection as implied through the in silico molecular docking studies. CONCLUSIONS: Our research identified both the hydroalcoholic and aqueous extracts of Withania somnifera roots as potent inhibitors of HIV-1 infection. The in silico analyses also indicated the key components of Withania somnifera with the highest binding affinity against the HIV-1 Integrase by 12-Deoxywithastramonolide and 27-Hydroxywithanone, HIV-1 Protease by Ashwagandhanolide and Withacoagin, and HIV-1 Reverse transcriptase by Ashwagandhanolide and Withanolide B, thereby showing possible mechanisms of HIV-1 extenuation. Overall, this study classified the role of Withania somnifera extracts and their active compounds as potential agents against HIV-1 infection.

BACKGROUND: The possibilities of cross-species transmission of SARS-CoV-2 variants of concern (VOCs) between humans and poultry species are unknown. The analysis of the structure of receptor was used to investigate the potential of emerging SARS-CoV-2 VOCs to expand species tropism to chickens based on the interaction between Spike (S) protein and tyrosine kinase receptor UFO (AXL), angiotensin-converting enzyme 2 (ACE2), and neuropilin 1 (NRP1) with substantial public health importance. METHODS: The structural and genetic alignment and surface potential analysis of the amino acid (aa) in ACE2, AXL, and NRP1 in human, hamster, mouse, mink, ferret, rhesus monkey and chickens were performed by Swiss-Model and pymol software. The critical aa sites that determined the susceptibility of the SARS-CoV-2 to the host were screened by aligning the residues interfacing with the N-terminal domain (NTD) or receptor-binding domain (RBD) of Spike protein. RESULTS: The binding modes of chickens AXL and ACE2 to S protein are similar to that of the ferret. The spatial structure and electrostatic surface potential of NRP1 showed that SARS-CoV-2 VOCs could not invade chickens through NRP1 easily. CONCLUSION: These results suggested that emerging SARS-CoV-2 VOCs potentially expand the host range to chickens mainly through ACE2 and AXL receptors, while NRP1 receptor may rarely participate in the future epidemic of coronavirus disease 2019 in chickens.

BACKGROUND: Porcine circovirus type 2 (PCV2), a member of the genus Circovirus and family Circoviridae, is a closed, small, circular, and single-stranded DNA virus, and it is a crucial swine pathogen of porcine circovirus-associated diseases (PCVADs). PCV2 was first detected in PK-15(ATCC-CCL) cells in 1974, which has caused significant economic loss to the swine industry throughout the world. And the first case of PCV2 was reported in China in 2000. At present, PCV2d is the main genotype circulating widely in China. METHODS: Lymph samples were obtained from piglets with emaciation and respiratory disease in Guangxi province, China. The main pathogens were detected via PCR from lymph samples, and then PCV2-single positive samples were used to inoculate with PK-15 cells. After successive generations, the isolate was subsequently identified by polymerase chain reaction (PCR), immunofluorescence assay (IFA), Western blot (WB), and transmission electron microscopic (TEM). The full-length genome and genetic characterization of isolates were analyzed by Sanger sequencing. The TCID50 of the PCV2-GX-6 was determined by IFA, and the pathogenicity of PCV2 in BALB/c mice was analyzed via the mouse model. RESULTS: The isolates were successfully isolated from clinical samples. The complete genome of PCV2-GX-4, PCV2-GX-6, PCV2-GX-7, PCV2-GX-11 and PCV2-GX-16 have been amplified, sequenced, and deposited in GenBank (accession no.: OR133747, OQ803314, OR133748, OR133749, OR133750). Homology and phylogenetic analysis with reference strains showed that the isolates belonged to the PCV2d genotype. The PCV2-GX-6 could be stably passaged more than 30 times in PK-15 cells. PCV2-GX-6 was identified by PCR, IFA, WB and TEM. The results of homology showed that PCV2-GX-6 was closely related to the reference strains PCV2-JS17-8 (GenBank accession no.: MH211363). Pathogenicity studies in mice have shown that PCV2-GX-6 can lead to growth inhibition of mice. Meanwhile PCV2-GX-6 caused the typical lesions of spleen, lung and kidney. The results of qPCR showed that PCV2 can effectively proliferate in the liver, spleen, lung, and kidney. CONCLUSION: PCV2-GX-6 can successfully infect BLAB/c mice, effectively proliferate in major organs, and possessed high pathogenicity. In conclusion, combined with the genotype and pathogenicity of PCV2d currently prevalent, PCV2-GX-6 can be used as a candidate vaccine strain.

Influenza A viruses cause severe respiratory illnesses in humans and animals. Overreaction of the innate immune response to influenza virus infection results in hypercytokinemia, which is responsible for mortality and morbidity. The influenza A virus surface glycoprotein neuraminidase (NA) plays a vital role in viral attachment, entry, and virion release from infected cells. NA acts as a sialidase, which cleaves sialic acids from cell surface proteins and carbohydrate side chains on nascent virions. Here, we review progress in understanding the role of NA in modulating host immune response to influenza virus infection. We also discuss recent exciting findings targeting NA protein to interrupt influenza-induced immune injury.

BACKGROUND: Although three years after the outbreak of SARS-CoV-2, the virus is still having a significant impact on human health and the global economy. Infection through respiratory droplets is the main transmission route, but the transmission of the virus by surface contact cannot be ignored. Hand sanitizers and antiviral films can be applied to control SARS-CoV-2, but sanitizers and films show drawbacks such as resistance of the virus against ethanol and environmental problems including the overuse of plastics. Therefore, this study suggested applying natural substrates to hand sanitizers and antiviral films made of biodegradable plastic (PLA). This approach is expected to provide advantages for the easy control of SARS-CoV-2 through the application of natural substances. METHODS: Antiviral disinfectants and films were manufactured by adding caffeic acid and vanillin to ethanol, isopropyl alcohol, benzalkonium chloride, and PLA. Antiviral efficacies were evaluated with slightly modified international standard testing methods EN 14,476 and ISO 21,702. RESULTS: In suspension, all the hand sanitizers evaluated in this study showed a reduction of more than 4 log within 2 min against HCoV-229E. After natural substances were added to the hand sanitizers, the time needed to reach the detection limit of the viral titer was shortened both in suspension and porcine skin. However, no difference in the time needed to reach the detection limit of the viral titer was observed in benzalkonium chloride. In the case of antiviral films, those made using both PLA and natural substances showed a 1 log reduction of HCoV-229E compared to the neat PLA film for all treatment groups. Furthermore, the influence of the organic load was evaluated according to the number of contacts of the antiviral products with porcine skin. Ten rubs on the skin resulted in slightly higher antiviral activity than 50 rubs. CONCLUSION: This study revealed that caffeic acid and vanillin can be effectively used to control HCoV-229E for hand sanitizers and antiviral films. In addition, it is recommended to remove organic matter from the skin for maintaining the antiviral activity of hand sanitizer and antiviral film as the antiviral activity decreased as the organic load increased in this study.

BACKGROUND: The recent outbreak of the Coronavirus pandemic resulted in a successful vaccination program launched by the World Health Organization. However, a large population is still unvaccinated, leading to the emergence of mutated strains like alpha, beta, delta, and B.1.1.529 (Omicron). Recent reports from the World Health Organization raised concerns about the Omicron variant, which emerged in South Africa during a surge in COVID-19 cases in November 2021. Vaccines are not proven completely effective or safe against Omicron, leading to clinical trials for combating infection by the mutated virus. The absence of suitable pharmaceuticals has led scientists and clinicians to search for alternative and supplementary therapies, including dietary patterns, to reduce the effect of mutated strains. MAIN BODY: This review analyzed Coronavirus aetiology, epidemiology, and natural products for combating Omicron. Although the literature search did not include keywords related to in silico or computational research, in silico investigations were emphasized in this study. Molecular docking was implemented to compare the interaction between natural products and Chloroquine with the ACE2 receptor protein amino acid residues of Omicron. The global Omicron infection proceeding SARS-CoV-2 vaccination was also elucidated. The docking results suggest that DGCG may bind to the ACE2 receptor three times more effectively than standard chloroquine. CONCLUSION: The emergence of the Omicron variant has highlighted the need for alternative therapies to reduce the impact of mutated strains. The current review suggests that natural products such as DGCG may be effective in binding to the ACE2 receptor and combating the Omicron variant, however, further research is required to validate the results of this study and explore the potential of natural products to mitigate COVID-19.

BACKGROUND: The SARS-CoV-2 Omicron strain has multiple immune-escape mutations in the spike protein receptor-binding domain (RBD). Rapid detection of these mutations to identify Omicron and its lineages is essential for guiding public health strategies and patient treatments. We developed a two-tube, four-color assay employing asymmetric polymerase chain reaction (PCR)-based melting curve analysis to detect Omicron mutations and discriminate the BA.1, BA.2, BA.4/5, and BA.2.75 lineages. METHODS: The presented technique involves combinatory analysis of the detection of six fluorescent probes targeting the immune-escape mutations L452R, N460K, E484A, F486V, Q493R, Q498R, and Y505H within one amplicon in the spike RBD and probes targeting the ORF1ab and N genes. After protocol optimization, the analytical performance of the technique was evaluated using plasmid templates. Sensitivity was assessed based on the limit of detection (LOD), and reliability was assessed by calculating the intra- and inter-run precision of melting temperatures (Tms). Specificity was assessed using pseudotyped lentivirus of common human respiratory pathogens and human genomic DNA. The assay was used to analyze 40 SARS-CoV-2-positive clinical samples (including 36 BA.2 and 4 BA.4/5 samples) and pseudotyped lentiviruses of wild-type and BA.1 viral RNA control materials, as well as 20 SARS-CoV-2-negative clinical samples, and its accuracy was evaluated by comparing the results with those of sequencing. RESULTS: All genotypes were sensitively identified using the developed method with a LOD of 39.1 copies per reaction. The intra- and inter-run coefficients of variation for the Tms were ≤ 0.69% and ≤ 0.84%, with standard deviations ≤ 0.38 °C and ≤ 0.41 °C, respectively. Validation of the assay using known SARS-CoV-2-positive samples demonstrated its ability to correctly identify the targeted mutations and preliminarily characterize the Omicron lineages. CONCLUSION: The developed assay can provide accurate, reliable, rapid, simple and low-cost detection of the immune-escape mutations located in the spike RBD to detect the Omicron variant and discriminate its lineages, and its use can be easily generalized in clinical laboratories with a fluorescent PCR platform.

Members of the family Polyomaviridae have a circular double-stranded DNA genome that have been identified in various hosts ranging from mammals to arachnids. Here we report the identification and analysis of a complete genome sequence of a novel polyomavirus, Raja clavata polyomavirus (RcPyV1), from a cartilaginous fish, the thornback skate (Raja clavata). The genome sequence was determined using a metagenomics approach with an aim to provide baseline viral data in cartilaginous fish in different ecosystems. The RcPyV1 genome (4,195 nucleotides) had typical organization of polyomavirus, including early antigens (small T; Large T) encoded on one strand and late viral proteins (VP1; VP2) on the complementary strand. Maximum-likelihood phylogenetic analysis of the large T-antigen revealed that RcPyV1 clusters with a polyomavirus obtained from another cartilaginous fish, the guitarfish polyomavirus 1 (GfPyV1). These two share ~ 56% pairwise identity in LT and VP1 protein sequences. These analyses support the hypothesis that cartilaginous fishes have a specific lineage of polyomaviruses.

BACKGROUND: The emergence of COVID-19 and the implementation of preventive measures and behavioral changes have led to a significant decrease in the prevalence of other respiratory viruses. However, the manner in which seasonal viruses will reemerge in the absence of COVID-19-related restrictions remains unknown. METHODS: Patients presenting with influenza-like illness in two hospitals in Beijing were subjected to testing for COVID-19, influenza A, and influenza B to determine the causative agent for viral infections. The prevalence of influenza B across China was confirmed using data from the Centers for Disease Control, China (China CDC). Clinical characteristics, laboratory findings, imaging results, and mortality data were collected for a cohort of 70 hospitalized patients with confirmed influenza B from 9 hospitals across China. RESULTS: Starting from October 2021, a substantial increase in the number of patients visiting the designated fever clinics in Beijing was observed, with this trend continuing until January 2022. COVID-19 tests conducted on these patients yielded negative results, while the positivity rate for influenza rose from approximately 8% in October 2021 to over 40% by late January 2022. The cases started to decline after this peak. Data from China CDC confirmed that influenza B is a major pathogen during the season. Sequencing of the viral strain revealed the presence of the Victoria-like lineage of the influenza B strain, with minor variations from the Florida/39/2018 strain. Analysis of the hospitalized patients' characteristics indicated that severe cases were relatively more prevalent among younger individuals, with an average age of 40.9 ± 24.1 years. Among the seven patients who succumbed to influenza, the average age was 30 ± 30.1 years. These patients exhibited secondary infections involving either bacterial or fungal pathogens and displayed elevated levels of cell death markers (such as LDH) and coagulation pathway markers (D-dimer). CONCLUSION: Influenza B represents a significant infection threat and can lead to substantial morbidity and mortality, particularly among young patients. To mitigate morbidity and mortality rates, it is imperative to implement appropriate vaccination and other preventive strategies.

BACKGROUND: Limited data exists on herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections in migrant populations. This study investigated HSV-1 and HSV-2 seroprevalences and associations among craft and manual workers (CMWs) in Qatar who constitute 60% of Qatar's population. METHODS: A national population-based cross-sectional seroprevalence survey was conducted on the CMW population, all men, between July 26 and September 9, 2020. 2,612 sera were tested for anti-HSV-1 IgG antibodies using HerpeSelect 1 ELISA IgG kits and for anti-HSV-2 IgG antibodies using HerpeSelect 2 ELISA IgG kits (Focus Diagnostics, USA). Univariable and multivariable logistic regression analyses were conducted to identify associations with HSV-1 and HSV-2 infections. RESULTS: Serological testing identified 2,171 sera as positive, 403 as negative, and 38 as equivocal for HSV-1 antibodies, and 300 sera as positive, 2,250 as negative, and 62 as equivocal for HSV-2 antibodies. HSV-1 and HSV-2 seroprevalences among CMWs were estimated at 84.2% (95% CI 82.8-85.6%) and 11.4% (95% CI 10.1-12.6%), respectively. HSV-1 infection was associated with nationality, educational attainment, and occupation. HSV-2 infection was associated with age, nationality, and educational attainment. CONCLUSIONS: Over 80% of CMWs are infected with HSV-1 and over 10% are infected with HSV-2. The findings highlight the need for sexual health programs to tackle sexually transmitted infections among the CMW population.

BACKGROUND: Influenza A virus (IAV) causes respiratory disease in pigs and is a major concern for public health. Vaccination of pigs is the most successful measure to mitigate the impact of the disease in the herds. Influenza-based virosome is an effective immunomodulating carrier that replicates the natural antigen presentation pathway and has tolerability profile due to their purity and biocompatibility. METHODS: This study aimed to develop a polyvalent virosome influenza vaccine containing the hemagglutinin and neuraminidase proteins derived from the swine IAVs (swIAVs) H1N1, H1N2 and H3N2 subtypes, and to investigate its effectiveness in mice as a potential vaccine for swine. Mice were immunized with two vaccine doses (1 and 15 days), intramuscularly and intranasally. At 21 days and eight months later after the second vaccine dose, mice were euthanized. The humoral and cellular immune responses in mice vaccinated intranasally or intramuscularly with a polyvalent influenza virosomal vaccine were investigated. RESULTS: Only intramuscular vaccination induced high hemagglutination inhibition (HI) titers. Seroconversion and seroprotection (> 4-fold rise in HI antibody titers, reaching a titer of ≥ 1:40) were achieved in 80% of mice (intramuscularly vaccinated group) at 21 days after booster immunization. Virus-neutralizing antibody titers against IAV were detected at 8 months after vaccination, indicating long-lasting immunity. Overall, mice immunized with the virosome displayed greater ability for B, effector-T and memory-T cells from the spleen to respond to H1N1, H1N2 and H3N2 antigens. CONCLUSIONS: All findings showed an efficient immune response against IAVs in mice vaccinated with a polyvalent virosome-based influenza vaccine.

The genomic components of multipartite viruses are encapsidated in separate virus particles, and the frequencies of genomic components represent one of the key genetic features. Many begomoviruses of economic significance are bipartite, and the details of the association between their genomic components remain largely unexplored. We first analyzed the temporal dynamics of the quantities of DNA-A and DNA-B and the B/A ratio of the squash leaf curl China virus (SLCCNV) in plants and found that while the quantities of DNA-A and DNA-B varied significantly during infection, the B/A ratio remained constant. We then found that changes in the B/A ratio in agrobacteria inoculum may significantly alter the B/A ratio in plants at 6 days post inoculation, but the differences disappeared shortly thereafter. We next showed that while the quantities of DNA-A and DNA-B among plants infected by agrobacteria, sap transmission and whitefly-mediated transmission differed significantly, the B/A ratios were similar. Further analysis of gene expression revealed that the ratio of the expression of genes encoded by DNA-A and DNA-B varied significantly during infection. Finally, we monitored the temporal dynamics of the quantities of DNA-A and DNA-B and the B/A ratio of another bipartite begomovirus, and a constant B/A ratio was similarly observed. Our findings highlight the maintenance of a constant ratio between the two genomic components of bipartite begomoviruses during infection and transmission, and provide new insights into the biology of begomoviruses.

BACKGROUND: HTLV-1-associated uveitis (HAU) is an inflammatory reaction of the choroid, retina, optic nerve and vitreous that can lead to vision impairment. The worldwide prevalence of HAU varies widely. OBJECTIVE: To determine the prevalence of HAU in patients from Salvador, Bahia-Brazil, and describe uveitis type and associated symptoms. METHODS: Cross-sectional analytical study to determine the prevalence of uveitis in HTLV-1-infected patients recruited in Bahia, Brazil, a region considered endemic for HTLV-1. Patients were enrolled at a local reference center for HTLV (infected) and at an outpatient ophthalmology clinic (noninfected group). All patients were examined by the same ophthalmologist following a single protocol. Prevalence ratios (PR) were calculated. RESULTS: A total of 168 consecutively examined HTLV-1-infected patients and 410 noninfected patients (randomly selected) were included. Females predominated (82.1%) in the HTLV-1-infected group (versus 64.4% in the uninfected group) (p < 0.001). The mean age of infected and uninfected patients was 53.2 and 62.8 years, respectively (p < 0.001). The prevalence of uveitis in HTLV-1+ and HTLV-1- patients was 7.14% and 0.73%, respectively (PR = 9.76; 95CI%:2.79-34.15; p < 0.01). Bilateral intermediate uveitis, associated with symptoms including visual disturbances and floaters, was most commonly identified in the HTLV-1-infected patients, whereas unilateral anterior uveitis, in association with symptoms such as blurring and ocular pain, was more common in the uninfected group. CONCLUSION: The prevalence of uveitis in patients with HTLV-1 was markedly higher than in uninfected subjects. HAU patients were mostly asymptomatic and exhibited bilateral presentation, with uveitis more frequently localized in the intermediate chamber.

Coronavirus disease 2019 (COVID-19) is an acute respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which can lead to acute respiratory distress syndrome (ARDS), multi-organ failure and death, posing significant threat to human health. Studies have found that pathological mechanisms, such as cytokine storms caused by uncontrolled innate immune system activation, release of damage-associated molecular patterns during tissue injury and a high incidence of thrombotic events, are associated with the function and dysfunction of neutrophils. Specifically, the increased formation of low-density neutrophils (LDNs) and neutrophil extracellular traps (NETs) has been shown to be closely linked with the severity and poor prognosis in patients with COVID-19. Our work focuses on understanding the increased number, abnormal activation, lung tissue infiltration, and elevated neutrophil-to-lymphocyte ratio in the pathogenesis of COVID-19. We also explore the involvement of NETs and LDNs in disease progression and thrombosis formation, along with potential therapeutic strategies targeting neutrophil and NETs formation.

BACKGROUND: Human adenoviruses (HAdV) have been known to cause a range of diseases, including respiratory tract infections (RTIs). However, there is limited information available regarding the genotype diversity and epidemiology of HAdV associated with RTIs in Nanning. METHODS: Between June 2019 and December 2021, throat swab, nasal swab, or nasopharyngeal swab samples were obtained from individuals hospitalized with respiratory tract infections (RTIs). Statistical software was used to analyze the epidemiological data. The highly conserved 132-bp gene region of the HAdV hexon was targeted for the detection of HAdV using a qPCR assay. An 875-bp hexon gene fragment was subjected to phylogenetic analysis. RESULTS: Significant variations were observed in the age and gender distribution of HAdV-positive patients (P = 0.004 and P = 0.025, respectively). The age distribution of HAdV-positive patients showed that 67.89% of those who tested positive were the age group of 0-6 years. Furthermore, the prevalence of HAdV detection was highest during spring and autumn, with a peak in February. Additionally, genotyping of the 36 HAdV-positive samples with 875-bp fragments identified the presence of circulating HAdV species B, C, and E in Nanning between 2019 and 2021. CONCLUSIONS: This study identified an association between HAdV prevalence and age as well as season. Among hospitalized patients with RTIs in Nanning, HAdV-B, HAdV-C, and HAdV-E were found to be co-circulating. The most commonly detected genotypes were HAdV-C1, HAdV-C6, and HAdV-E4.

Viral infections of the central nervous system (CNS) are common worldwide and result in considerable morbidity and mortality associated with neurologic illness. Until now, there have been no epidemiologic data regarding viruses causing aseptic meningitis, encephalitis, and CNS infections in Egypt. We investigated 1735 archived cerebrospinal fluid samples collected from Egyptian patients between 2016 and 2019 and performed molecular characterization for infection for12 different viruses: herpes simplex viruses 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpesviruses 6 and 7 (HHV-6 and HHV-7), human enteroviruses (HEVs), human parechovirus (HPeV), parvovirus B19 (B19V), adenovirus (AdV), and mumps virus (MuV). All included samples were negative for bacterial infection. Our results indicated a relatively high prevalence of viral infection, with HEVs being the most prevalent viruses, followed by HSV-1, EBV, and then HSV-2. The highest prevalence was among male patients, peaking during the summer. Data obtained from this study will contribute to improving the clinical management of viral infections of the CNS in Egypt.

Acute flaccid paralysis (AFP) is a rare side effect of the oral polio vaccine but can be associated with outbreaks and permanent disability in patients harboring circulating vaccine-derived polioviruses (cVDPVs). With the advancement of polio abolition in a glimpse, cVDPVs are causing outbreaks and slowing the polio eradication process. The polio virus protein 1 (VP1) contains the binding site that is key for virus transmission. Understanding the evolution of VP1 among AFP patients could yield more insight into the early events of cVDPVs. Polioviruses were identified from stool specimens of AFP patients using cell culture; and confirmed by the real time RT PCR intra-typic differentiation and vaccine-derived poliovirus assays. Seventy-nine (79) Sabin-like poliovirus 1 (SL1) and 86 Sabin-like poliovirus 3 (SL3) were sequenced. The VP1 amino acid substitutions T106A in Sabin poliovirus 1 and A54V in Sabin poliovirus 3 were common among the AFP patients as has been found in previous studies. Other substitutions that were associated with AFP were: T290A and A54T in SL1 and SL3 respectively. Nucleotide mutations that were common among the AFP patients included T402C, C670A, and T816C in SL1, and G22A, C375Y, A472R, and A694T in SL3 polioviruses. Characterizing mutations that are associated with AFP could contribute to efforts pursued to mitigate the risk of vaccine-derived polioviruses and promote development of safer vaccines.

BACKGROUND/AIMS: The aim of this study was to determine the rate of natural and breakthrough infection and related symptoms of Covid-19 amongst Iranian healthcare workers (HCWs) who were vaccinated by different non-mRNA-based vaccines at peak points. METHODS: In this cross-sectional study, the RT-PCR test was performed for a total of 10,581 HCWs suspicious of Covid-19 infection. For each HCW, the frequency of SARS-CoV-2 infection and the time of transmission based on vaccination administration time and schedule were examined during different waves of the pandemic. Based on these findings, the study patients were divided into three groups: natural, natural/breakthrough, and breakthrough. RESULTS: In total, 53% of the HCWs were exposed to SARS-CoV-2 infection between 1 and 5 times within two years after the current pandemic, while 20.7% and 32.3% experienced natural and breakthrough SARS-CoV-2 infection, respectively. Only 6% of the breakthrough-infected HCWs had naturally contracted SARS-CoV-2 infection during the initial waves. The highest natural peaks of infection occurred during the interval administration of the first and second dose of the first vaccination series, while the single highest peak of breakthrough infection belonged to the Omicron wave. It occurred simultaneously with the administration of the third vaccination dose. On the other hand, the highest rate of reinfection was observed amongst people who had received the Sinopharm and Bharat vaccines full-doses. CONCLUSION: This study compared the clinical differences between the two peaks of Omicron and Delta. This study indicates the rates of natural and breakthrough SARS-CoV-2 infections according to vaccination schedules and different waves of the pandemic.

The antiviral response against influenza A virus (IAV) infection includes the induction of the interferon (IFN) signaling pathway, including activation of the STATs protein family. Subsequently, antiviral myxovirus resistance (MxA) protein and other interferon-stimulated genes control virus replication; however, the molecular interaction of viral-mediated IFN signaling needs more investigation. Host microRNAs (miRNAs) are small non-coding molecules that posttranscriptionally regulate gene expression. Here, we sought to investigate the possible involvement of miR-141 in IAV-mediated IFN signaling. Accordingly, the microarray analysis of A549 cells transfected with precursor miR-141 (pre-miR-141) was used to capture the potentially regulated genes in response to miR-141 overexpression independent of IAV infection. The downregulation of targeted genes by miR-141, in addition to viral gene expression, was investigated by quantitative real-time PCR, western blot analysis, and flow cytometric assay. Our findings showed a significant upregulation of miR-141 in infected A549 cells with different strains of IAV. Notably, IAV replication was firmly interrupted in cells transfected with the miR-141 inhibitor. While its replication significantly increased in cells transfected with pre-miR-141 confirming the crucial role of miRNA-141 in supporting virus replication. Interestingly, the microarray data of miR-141 transduced A549 cells showed many downregulated genes, including MxA, STAT3, IFI27, and LAMP3. The expression profile of MxA and STAT3 was significantly depleted in infected cells transfected with the pre-miR-141, while their expression was restored in infected cells transfected with the miR-141 inhibitor. Unlike interleukin 6 (IL-6), the production of IFN-β markedly decreased in infected cells that transfected with pre-miR-141, while it significantly elevated in infected cells transfected with miR-141 inhibitor. These data provide evidence for the crucial role of miR-141 in regulating the antiviral gene expression induced by IFN and IL-6 signaling during IAV infection to ensure virus replication.

BACKGROUND: Influenza A virus (IAV) is endemic in pigs globally and co-circulation of genetically and antigenically diverse virus lineages of subtypes H1N1, H1N2 and H3N2 is a challenge for the development of effective vaccines. Virosomes are virus-like particles that mimic virus infection and have proven to be a successful vaccine platform against several animal and human viruses. METHODS: This study evaluated the immunogenicity of a virosome-based influenza vaccine containing the surface glycoproteins of H1N1 pandemic, H1N2 and H3N2 in pigs. RESULTS: A robust humoral and cellular immune response was induced against the three IAV subtypes in pigs after two vaccine doses. The influenza virosome vaccine elicited hemagglutinin-specific antibodies and virus-neutralizing activity. Furthermore, it induced a significant maturation of macrophages, and proliferation of B lymphocytes, effector and central memory CD4+ and CD8+ T cells, and CD8+ T lymphocytes producing interferon-γ. Also, the vaccine demonstrated potential to confer long-lasting immunity until the market age of pigs and proved to be safe and non-cytotoxic to pigs. CONCLUSIONS: This virosome platform allows flexibility to adjust the vaccine content to reflect the diversity of circulating IAVs in swine in Brazil. The vaccination of pigs may reduce the impact of the disease on swine production and the risk of swine-to-human transmission.

BACKGROUND: Our study aimed to compare the predictive performance of different hepatocellular carcinoma (HCC) prediction models in chronic hepatitis B patients receiving entecavir or tenofovir, including discrimination, calibration, negative predictive value (NPV) in low-risk, and proportion of low-risk. METHODS: We conducted a systematic literature research in PubMed, EMbase, the Cochrane Library, and Web of Science before January 13, 2022. The predictive performance was assessed by area under receiver operating characteristic curve (AUROC), calibration index, negative predictive value, and the proportion in low-risk. Subgroup and meta-regression analyses of discrimination and calibration were conducted. Sensitivity analysis was conducted to validate the stability of the results. RESULTS: We identified ten prediction models in 23 studies. The pooled 3-, 5-, and 10-year AUROC varied from 0.72 to 0.84, 0.74 to 0.83, and 0.76 to 0.86, respectively. REAL-B, AASL-HCC, and HCC-RESCUE achieved the best discrimination. HCC-RESCUE, PAGE-B, and mPAGE-B overestimated HCC development, whereas mREACH-B, AASL-HCC, REAL-B, CAMD, CAGE-B, SAGE-B, and aMAP underestimated it. All models were able to identify people with a low risk of HCC accurately. HCC-RESCUE and aMAP recognized over half of the population as low-risk. Subgroup analysis and sensitivity analysis showed similar results. CONCLUSION: Considering the predictive performance of all four aspects, we suggest that HCC-RESCUE was the best model to utilize in clinical practice, especially in primary care and low-income areas. To confirm our findings, further validation studies with the above four components were required.

BACKGROUND: Ibrutinib is a Bruton's tyrosine kinase (BTK) inhibitor approved for the treatment for several mature B-cell malignancies. Reactivation of hepatitis B virus (HBV) is a well-described complication in patients with chronic HBV infection or prior HBV exposure undergoing cytotoxic or immunosuppressive chemotherapy for hematologic malignancies. This phenomenon has been frequently reported with rituximab. However, published data on the risk of HBV reactivation induced by ibrutinib are scarce. Cases of HBV reactivation in hematologic patients receiving ibrutinib therapy have recently been described, but limited only to overt hepatitis B patients or seropositive occult hepatitis B patients. CASE PRESENTATION: We report the first case of HBV reactivation during ibrutinib treatment in an asymptomatic 82-year-old woman with seronegative occult hepatitis B patient (i.e., negative for HBsAg, anti-HBc and anti-HBs). Four months after ibrutinib treatment, her liver function test (LFT) was deranged, with seroconversion to HBsAg positivity. Serum hepatitis B virus DNA was quantified to be 1.92 × 108 IU/ml. Antiviral treatment was initiated, and viral load was gradually suppressed with improvement in LFT. CONCLUSIONS: Our case illustrated that in populations with a high incidence of HBV exposure, systematic screening for HBV exposure is essential prior to ibrutinib treatment, followed by serial monitoring of serologic and molecular markers of hepatitis B. There is a need for an international consensus to support the recommendation of antiviral prophylaxis against HBV reactivation in patients using ibrutinib.