Important Viral Pathogens Research Articles

Unveiling viral pathogens in acute respiratory disease: Insights from viral metagenomics in patients from the State of Alagoas, Brazil.

Respiratory illness affects individuals across all age demographics on a global scale, often precipitated by viral infections. The symptomatic manifestations of these diseases bear clinical resemblance, complicating the accurate determination of their etiological origins. Furthermore, the diagnostic panels for respiratory pathogens used within local medical practices, may not encompass the full spectrum of viral agents responsible for such ailments. Consequently, a significant number of clinically important viral pathogens may remain undetected. In the light of this, we conducted a metagenomic examination of 66 nasopharyngeal swab specimens, obtained from patients presenting with acute respiratory conditions yet tested negative by the standard diagnostic panels available locally. These specimens were obtained from the Public Health Laboratory, Maceio, State of Alagoas. Our findings indicate a predominant diagnostic escape of rhinoviruses and notably enterovirus D68. Moreover, our study identified a substantial quantity of sequence reads attributed to human respirovirus 3 (human parainfluenza 3) along with various herpresviruses including human herpesvirus-1, Epstein-Barr virus (Human herpesvirus-4), Human herpesviruses 6 and 7 and human parvovirus B19 (B19V). Notably, the metagenomic analysis uncovered a widespread presence of the emerging human vientovirus FB in most of sample pools, though its clinical importance remains to be elucidated. The obtained results in this study underscore the invaluable role of viral metagenomics in the identification of underrecognized viruses bearing clinical relevance. Furthermore, it offers insights into the dissemination of these pathogens within the studied area, thereby informing public health strategies aimed at enhancing diagnostic accuracy and improving patient care.

Bile acid-sensitive human norovirus strains are susceptible to sphingosine-1-phosphate receptor 2 inhibition.

Human noroviruses (HuNoVs) are a diverse group of RNA viruses that cause endemic and pandemic acute viral gastroenteritis. Previously, we reported that many HuNoV strains require bile or bile acid (BA) to infect human jejunal intestinal enteroid cultures. BA was not essential for the replication of a pandemic-causing GII.4 HuNoV strain. We found the hydrophobic BA glycochenodeoxycholic acid (GCDCA) promotes the replication of the BA-dependent strain GII.3 in jejunal enteroids. Furthermore, we found that inhibition of the G-protein-coupled BA receptor, sphingosine-1-phosphate receptor 2 (S1PR2), by JTE-013, reduced GII.3 infection dose-dependently and inhibited GII.3 cellular uptake in enteroids. Herein, we sought to determine whether S1PR2 is required for other BA-dependent HuNoV strains, the BA-independent GII.4, and whether S1PR2 is required for BA-dependent HuNoV infection in HIEs from other small intestinal segments. We found a second S1PR2 inhibitor, GLPG2938, reduces GII.3 infection dose-dependently, and an S1PR2 agonist (CYM-5520) enhances GII.3 replication in the absence of GCDCA. GII.3 replication also is abrogated in the presence of JTE-013 and CYM-5520. JTE-013 inhibition of S1PR2 in jejunal HIEs reduces GI.1, GII.3, and GII.17 (BA-dependent) but not GII.4 Sydney (BA-independent) infection, providing additional evidence of strain-specific differences in HuNoV infection. Finally, GII.3 infection of duodenal, jejunal, and ileal lines derived from the same individual is reduced with S1PR2 inhibition, indicating a common mechanism of BA-dependent infection among multiple segments of the small intestine. Our results support a model where BA-dependent HuNoVs exploit BA effects on S1PR2 to infect the entire small intestine.IMPORTANCEHuman noroviruses (HuNoVs) are important viral human pathogens that cause both outbreaks and sporadic gastroenteritis. These viruses are diverse, and many strains are capable of infecting humans. Our previous studies have identified strain-specific requirements for hydrophobic bile acids (BAs) to infect intestinal epithelial cells. Moreover, we identified a BA receptor, sphingosine-1-phosphate receptor 2 (S1PR2), required for infection by a BA-dependent strain. To better understand how various HuNoV strains enter and infect the small intestine and the role of S1PR2 in HuNoV infection, we evaluated infection by additional HuNoV strains using an expanded repertoire of intestinal enteroid cell lines. We found that multiple BA-dependent strains, but not a BA-independent strain, all require S1PR2 for infection. In addition, BA-dependent infection requires S1PR2 in multiple segments of the small intestine. Together, these results indicate that S1PR2 has value as a potential therapeutic target for BA-dependent HuNoV infection.

Protective Effects from Prior Pneumococcal Vaccination in Patients with Chronic Airway Diseases during Hospitalization for Influenza-A Territory-Wide Study.

Influenza is an important respiratory viral pathogen in adults, with secondary bacterial pneumonia being a common complication. While pneumococcal vaccines can prevent pneumococcal pneumonia and invasive pneumococcal disease, whether they can also prevent the severe in-hospital outcomes among patients hospitalized for influenza has not been examined. A territory-wide retrospective study was conducted in Hong Kong, which included all adult patients having chronic airway diseases (asthma, bronchiectasis, and chronic obstructive pulmonary disease) hospitalized for influenza and who had received seasonal influenza vaccine. The occurrence of secondary bacterial pneumonia, mortality, and other severe in-hospital outcomes were compared among subjects with or without pneumococcal vaccination. There was a total of 3066 eligible patients who were hospitalized for influenza in public hospitals in Hong Kong from 1 January 2016 to 30 June 2023. Completed pneumococcal vaccination with PSV23/PCV13 conferred protection against secondary bacterial pneumonia, all-cause mortality, and respiratory cause of mortality with adjusted odds ratios of 0.74 (95% CI = 0.57-0.95, p = 0.019), 0.12 (95% CI = 0.03-0.53, p = 0.005), and 0.04 (95% CI = 0.00-0.527, p = 0.0038), respectively.

Characterization of the proteins encoded by a recently emerged cotton-infecting Polerovirus

The cotton leafroll dwarf virus (CLDV), an important viral pathogen responsible for substantial losses in cotton crops, has recently emerged in the United States (US). Although CLDV shares similarities with other members of the genus Polerovirus in terms of encoded proteins, their functional characteristics remain largely unexplored. In this study, we expressed and analyzed each protein encoded by CLDV to determine its intracellular localization using fluorescence protein fusion. We also evaluated their potential to induce plant responses, such as the induction of hypersensitive response-like necrosis and the generation of reactive oxygen species. Our findings show that the proteins encoded by CLDV exhibit comparable localization patterns and elicit similar robust plant responses as observed with cognate proteins from other viruses within the genus Polerovirus. This study contributes to our understanding of the functional repertoire of genes carried by Polerovirus members, particularly to CLDV that has recently emerged as a widespread viral pathogen infecting cotton in the US.

Innate immune response against vector-borne bunyavirus infection and viral countermeasures.

Bunyaviruses are a large group of important viral pathogens that cause significant diseases in humans and animals worldwide. Bunyaviruses are enveloped, single-stranded, negative-sense RNA viruses that infect a wide range of hosts. Upon entry into host cells, the components of viruses are recognized by host innate immune system, leading to the activation of downstream signaling cascades to induce interferons (IFNs) and other proinflammatory cytokines. IFNs bind to their receptors and upregulate the expression of hundreds of interferon-stimulated genes (ISGs). Many ISGs have antiviral activities and confer an antiviral state to host cells. For efficient replication and spread, viruses have evolved different strategies to antagonize IFN-mediated restriction. Here, we discuss recent advances in our understanding of the interactions between bunyaviruses and host innate immune response.

Genome-Wide Association Analysis of Cowpea Mild Mottle Virus Resistance in Soybean Germplasms from Northeast China

Cowpea mild mottle virus (CpMMV) is an important viral pathogen that seriously influences the yield and seed quality of soybeans worldwide. Resistance breeding is one of the most effective, economical, and environmentally safe strategies for controlling the disease caused by CpMMV. However, only few resistance genes have been identified in soybeans. In this study, the resistance of 169 soybean germplasms from Northeast China to a CpMMV strain isolated from soybean in China was evaluated, and a genome-wide association study (GWAS) was then performed to find possible resistance genes in these soybean germplasms. Nine resistant soybean germplasms were identified and two single nucleotide polymorphism sites (SNPs) were found to be closely associated with CpMMV resistance. A total number of 51 and 25 candidate genes neighboring the resistance-associated SNPs on chromosomes 6 and 12, respectively, were identified, among which one receptor-like kinase (RLK) on chromosome 6 and 2 toll-interleukin-1 receptor nucleotide-binding leucine-rich repeat receptors (TNLs) on chromosome 12 were recognized as the most probable resistance genes, respectively. Together, these data provide new insights on the resistance resources of soybeans to CpMMV, which will benefit the breeding of CpMMV-resistant soybean cultivars.

Antiviral responses versus virus-induced cellular shutoff: a game of thrones between influenza A virus NS1 and SARS-CoV-2 Nsp1.

Following virus recognition of host cell receptors and viral particle/genome internalization, viruses replicate in the host via hijacking essential host cell machinery components to evade the provoked antiviral innate immunity against the invading pathogen. Respiratory viral infections are usually acute with the ability to activate pattern recognition receptors (PRRs) in/on host cells, resulting in the production and release of interferons (IFNs), proinflammatory cytokines, chemokines, and IFN-stimulated genes (ISGs) to reduce virus fitness and mitigate infection. Nevertheless, the game between viruses and the host is a complicated and dynamic process, in which they restrict each other via specific factors to maintain their own advantages and win this game. The primary role of the non-structural protein 1 (NS1 and Nsp1) of influenza A viruses (IAV) and the pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), respectively, is to control antiviral host-induced innate immune responses. This review provides a comprehensive overview of the genesis, spatial structure, viral and cellular interactors, and the mechanisms underlying the unique biological functions of IAV NS1 and SARS-CoV-2 Nsp1 in infected host cells. We also highlight the role of both non-structural proteins in modulating viral replication and pathogenicity. Eventually, and because of their important role during viral infection, we also describe their promising potential as targets for antiviral therapy and the development of live attenuated vaccines (LAV). Conclusively, both IAV NS1 and SARS-CoV-2 Nsp1 play an important role in virus-host interactions, viral replication, and pathogenesis, and pave the way to develop novel prophylactic and/or therapeutic interventions for the treatment of these important human respiratory viral pathogens.

Prevalence of Influenza Viruses A and B, Adenovirus, Respiratory Syncytial Virus, and Human Metapneumonia Viruses among Children with Acute Respiratory Tract Infection.

Acute respiratory tract infection (ARTI) is a significant cause of morbidity and mortality among children worldwide. The majority of acute respiratory infections in children are caused by viruses, with respiratory syncytial virus (RSV) being the most frequently encountered. Other important viral pathogens include human metapneumovirus, human coronaviruses, adenovirus, and influenza. These infections can lead to complications such as bronchitis and pneumonia. So, this study aimed to evaluate the prevalence of influenza viruses A and B, adenovirus, respiratory syncytial virus (RSV), and human metapneumovirus (HMPV) in children with ARTI. The molecular diagnostic of polymerase chain reaction approach was used to detect influenza (A and B), metapneumovirus, respiratory syncytial virus (RSV), and adenovirus in respiratory samples of children with acute respiratory infection hospitalization in a teaching hospital of the Shiraz University of Medical Sciences in January 2016-March 2017. Of the 340 patients examined, 208 (61.20%) were male and the median age was 3.13 ± 2.38 years. Respiratory viruses were found in 179 (52.64%) patients. The male-to-female ratio was 1.63 : 1 in patients who were viral positive. Detection rates for influenza A, adenovirus, influenza B, RSV, and HMPV were 28.23%, 24.70%, 8.52%, 3.23%, and 2.64%, respectively, and coinfections were detected in 24.02%. The most common combination of two-virus coinfections was IFVA/AdV, followed by IFVB/AdV, AdV, IFVB/IFVA, RSV/IFVA, HMPV/AdV, RSV/AdV, and HMPV/IFVA. The high prevalence of respiratory viruses in children hospitalized with ARTI suggests that viral infection may play a role in disease pathogenesis. This should be confirmed through the conduct of case-control studies and may inform the role of vaccination to prevent respiratory viral infections.

Prevention of Cytomegalovirus Infection in Solid Organ Transplant Recipients: Guidelines by the Korean Society of Infectious Diseases and the Korean Society for Transplantation.

Cytomegalovirus (CMV) is the most important opportunistic viral pathogen in solid organ transplant (SOT) recipients. The Korean guideline for the prevention of CMV infection in SOT recipients was developed jointly by the Korean Society for Infectious Diseases and the Korean Society of Transplantation. CMV serostatus of both donors and recipients should be screened before transplantation to best assess the risk of CMV infection after SOT. Seronegative recipients receiving organs from seropositive donors face the highest risk, followed by seropositive recipients. Either antiviral prophylaxis or preemptive therapy can be used to prevent CMV infection. While both strategies have been demonstrated to prevent CMV infection post-transplant, each has its own advantages and disadvantages. CMV serostatus, transplant organ, other risk factors, and practical issues should be considered for the selection of preventive measures. There is no universal viral load threshold to guide treatment in preemptive therapy. Each institution should define and validate its own threshold. Valganciclovir is the favored agent for both prophylaxis and preemptive therapy. The evaluation of CMV-specific cell-mediated immunity and the monitoring of viral load kinetics are gaining interest, but there was insufficient evidence to issue recommendations. Specific considerations on pediatric transplant recipients are included.

Comparison of Polymerase Chain Reaction (PCR) assay performance in detecting Decapod penstylhamaparvovirus 1 in penaeid shrimp

Decapod Penstylhamaparvovirus 1, commonly known as infectious hypodermal and hematopoietic necrosis virus (IHHNV), remains an economically important viral pathogen for penaeid shrimp aquaculture due to its effects on growth performance. The World Organization for Animal Health (WOAH, Paris, France) recommended methods for the detection of IHHNV include both conventional and real-time PCR. However, published reports and anecdotal evidence suggest the occurrence of non-specific amplifications when testing for IHHNV using the WOAH protocols. Studies were designed to develop a sensitive, robust TaqMan PCR method for detection of IHHNV in the three commercially important penaeid shrimp: Penaeus vannamei, P. monodon and P. stylirostris. We compared the performance of the WOAH-recommended real-time PCR method to several published as well as in-house designed primer/probe sets spanning the entire genome of IHHNV. Our results show that (1) more than one primer/ probe set is needed when testing for the infectious form of IHHNV in all three species of shrimp and (2) primer pairs qIH-Fw/qIH-Rv and 3144F/ 3232R have diagnostic characteristics that would enable IHHNV detection in all three shrimp species. These findings are valuable for a large-scale screening of shrimp using a TaqMan real-time PCR assay.

Molecular detection of bovine alphaherpesvirus-1 in cases of reproductive disorders among cattle and buffaloes in Gujarat.

Bovine alphaherpesvirus-1 (BoAHV-1) is an important viral pathogen that causes significant economic losses to the dairy industry. The present study aimed to determine the prevalence of BoAHV-1 in cases of bovine reproductive disorder. Clinical samples were collected from various villages in Gujarat using specialized FTA® cards and were tested using real-time PCR assay targeting the gB gene of BoAHV-1. Out of 401 animals, 18.20% (95% CI: 14.74-22.28%) tested positive for BoAHV-1 DNA. The percentage positivity of BoAHV-1 was 20.37% in abortion cases and 19.55% in retention of fetal membrane cases, while only one out of nine metritis cases screened in the study was positive for BoAHV-1 DNA. A higher percentage positivity in buffaloes (22.14%) compared to cattle (16.30%) was recorded, but this difference was not statistically significant (p = 0.169). The frequency of BoAHV-1 detection was higher among crossbreeds (16.76%) and exotics (19.61%) than among indigenous cattle (8.82%), although this difference was not statistically significant (p = 0.400). There was also no significant difference in frequency distribution among animals of varying parity, ranging from 15.20 to 33.33% (p = 0.540). This study confirms the widespread circulation of BoAHV-1 and highlights the need for its control and prevention.

Genome and proteomic analysis of risk factors for fatal outcome in children with severe community-acquired pneumonia caused by human adenovirus 7.

Human adenovirus 7 (HAdV-7) is an important viral pathogen of severe pneumonia in children and a serious threat to health. A cohort of 45 pediatric patients diagnosed with HAdV-7-associated severe pneumonia and admitted to the Pediatric Intensive Care Unit at the Children's Hospital of Chongqing Medical University from May 2018 to January 2020 were included. Risk factors of death were analyzed by the Cox proportional risk mode with Clinical data, serum, and nasopharyngeal aspirate adenovirus load, Genome analysis, Olink proteomics, and cytokine profile between dead and surviving patients were also analyzed. A total of 45 children with a median age of 12.0 months (interquartile range [IQR]: 6.5, 22.0) were included (female 14), including 14 (31.1%) who died. High serum viral load was an independent risk factor for mortality (hazard ratio [HR] = 2.16, 95% confidence interval [CI], 1.04-4.49, p = 0.039). BTB and CNC homology 1 (BACH1), interleukin-5 (IL-5), and IL-9 levels were significantly correlated with serum viral load (p = 0.0400, 0.0499, and 0.0290; r = 0.4663, 0.3339, and -0.3700, respectively), with significant differences between the dead and survival groups (p = 0.021, 0.001, and 0.021). Severe cytokine storm-associated high serum viral load after HAdV-7 infection may be the main mechanism responsible for poor prognosis in children.

Corrected and republished from: "VP4 Is a Determinant of Alpha-Defensin Modulation of Rotaviral Infection".

Rotavirus is a leading cause of severe diarrhea in young children. Like other fecal-oral pathogens, rotaviruses encounter abundant, constitutively expressed defensins in the small intestine. These peptides are a vital part of the vertebrate innate immune system. By investigating the impact that defensins from multiple species have on the infectivity of different strains of rotavirus, we show that some rotaviral infections can be inhibited by defensins. We also found that rotaviruses may have evolved resistance to defensins in the intestine of their host species, and some even appropriate defensins to increase their infectivity. Because rotaviruses infect a broad range of animals and rotaviral infections are highly prevalent in children, identifying immune defenses against infection and how they vary across species and among viral genotypes is important for our understanding of the evolution, transmission, and zoonotic potential of these viruses as well as the improvement of vaccines.

The Temporal and Geographical Dynamics of Potato Virus Y Diversity in Russia.

Potato virus Y, an important viral pathogen of potato, has several genetic variants and geographic distributions which could be affected by environmental factors, aphid vectors, and reservoir plants. PVY is transmitted to virus-free potato plants by aphids and passed on to the next vegetative generations through tubers, but the effects of tuber transmission in PVY is largely unknown. By using high-throughput sequencing, we investigated PVY populations transmitted to potato plants by aphids in different climate zones of Russia, namely the Moscow and Astrakhan regions. We analyzed sprouts from the tubers produced by field-infected plants to investigate the impact of tuber transmission on PVY genetics. We found a significantly higher diversity of PVY isolates in the Astrakhan region, where winters are shorter and milder and summers are warmer compared to the Moscow region. While five PVY types, NTNa, NTNb, N:O, N-Wi, and SYR-I, were present in both regions, SYRI-II, SYRI-III, and 261-4 were only found in the Astrakhan region. All these recombinants were composed of the genome sections derived from PVY types O and N, but no full-length sequences of such types were present. The composition of the PVY variants in the tuber sprouts was not always the same as in their parental plants, suggesting that tuber transmission impacts PVY genetics.

Effect of Bacillus subtilis on potato virus Y (PVY) disease resistance and growth promotion in potato plants

Potato virus Y (PVY) has become the most important viral pathogen of potato. The Bacillus subtilis EMCCN 1211 (B. subtilis) isolate was investigated in the current study as a biocontrol agent for the management of the PVY and Induced Systemic Resistance (ISR) in potato plants under greenhouse conditions. Foliar and soil applications of a B. subtilis suspension at a concentration of 108 CFU/mL was applied at 48 h and 10 days respectively, before and after inoculation with PVY. Treatment of B. subtilis before virus inoculation resulted in a significant reduction in symptoms and entirely negative enzyme-linked immunosorbent assay (ELISA) results compared to untreated infected potato plants. In contrast, the RT-PCR showed PVY amplification (825 bp) in all bacterially treated plants. The soil application using B. subtilis before the PVY inoculation efficiently induced plant resistance and reduced the PVY accumulation level (32.79%) at 10 days post-inoculation (dpi) and continue with percentage increase of virus inhibition up to 72.26% at 35 dpi. The B. subtilis stimulated the plant growth that the potato plants fresh and dry weights increased by 61.40 and 56.6% at p ≤ 0.05 respectively. The transcriptional changes of pathogenesis -related gene (PR-1) was tested at 10 dpi. The results showed that the lower PVY accumulation was associated with the lower suppression of PR-1 defense related gene expression at 10 dpi and showed 0.9659 fold change value comparing with the mock-inoculated control. This data revealed that the soil application of B. subtilis efficiently suppressed, reduced the PVY accumulation level and symptoms severity; therefore it can be used as an antiviral biocontrol agent.

Taurochenodeoxycholic acid exerts anti-viral activities upon SGIV infection via anti-inflammatory response

Taurine chenodeoxycholic acid (TCDCA), a combination of taurine and chenodeoxycholic acid, plays anti-inflammatory roles in many diseases. However, little is known about its antiviral activity in aquaculture. Singapore grouper iridovirus (SGIV), a novel member of the genus Ranavirus, is an important viral pathogen in grouper aquaculture. Here, the effects of TCDCA on SGIV replication in vitro and in vivo were investigated. TCDCA treatment inhibited SGIV infection in grouper spleen (GS) cells, evidenced by the delayed CPE progression and decreased viral gene transcription, protein expression and viral progeny production. TCDCA treatment suppressed the mRNA level of pro-inflammatory factors and NF-κB promoter activities in SGIV-infected cells compared with mock-infected cells. Inhibition of NF-κB activity enhanced the inhibitory effects of TCDCA on SGIV replication, indicating that TCDCA inhibited SGIV replication in vitro via regulating host inflammatory response. Furthermore, TCDCA treatment protected grouper from SGIV infection, evidenced by the decreased mortality, the down-regulated transcription levels of viral genes and the improved pathological symptoms. In addition, the expression levels of SGIV induced pro-inflammation factors were decreased, while those of the antioxidant genes were increased after the supplement with TCDCA. Thus, our findings will not only contribute greatly to understanding the mechanism of SGIV pathogenesis, but also demonstrate that TCDCA might be a potential antiviral agent against SGIV infection.

Seed Transmission of Wheat Streak Mosaic Virus and Triticum Mosaic Virus in Differentially Resistant Wheat Cultivars.

Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV) are important viral pathogens of wheat in the Great Plains. These viruses individually or in mixed infections with High Plains wheat mosaic virus cause a devastating wheat streak mosaic (WSM) disease. Although seed transmission of WSMV has been studied, no information is currently available on that of TriMV. Furthermore, no study has explored the implications of mixed infections of WSMV and TriMV on seed transmission of one or both viruses. To study both aspects, seeds from differentially resistant field-grown wheat plants (cv. TAM 304 (susceptible), Joe (WSMV resistant, Wsm2 gene), and Breakthrough (BT) (WSMV and TriMV resistant, Wsm1 gene)) showing characteristic WSM symptoms were collected and analyzed to quantify both viruses using qRT-PCR. The percentage of seeds tested positive for WSMV or TriMV individually and in mixed infection varied with cultivar and virus combinations; 13% of TAM 304 seeds tested positive for WSMV, followed by 8% of BT and 4% of Joe seeds. Similarly, TriMV was detected in 12% of BT seeds, followed by 11% of TAM 304 and 8% of Joe seeds. Lastly, mixed infection was detected in 7% of TAM 304 seeds, followed by 4% in BT, and 2% in Joe. Dissection of field-collected seeds into three parts, embryo, endosperm, and seed coat, revealed both WSMV and TriMV accumulated only in the seed coat. Consistent with seeds, percent infection of WSMV or TriMV in the plants that emerged from infected seeds in each treatment varied with cultivar and virus combinations (WSMV: BT 3%; Joe 2%; TAM 304 9%; TriMV: BT 7%; Joe 8%; and TAM 304 10%). Plants infected with mixed viruses showed more pronounced WSM symptoms compared to individual infections. However, both viruses were present only in a few plants (BT: 2%, Joe: 1%, and TAM 304: 4%). Taken together, this study showed that TriMV was transmitted vertically at a higher frequency than WSMV in resistant cultivars, and the seed transmission of TriMV with WSMV increased the virulence of both pathogens (measured via WSM symptom severity) in the emerged plants. Furthermore, Wsm1 and Wsm2 genes considerably reduced WSMV transmission via infected seeds. However, no such effects were observed on TriMV, especially in progeny plants. These results reiterated the importance of planting clean seeds and highlighted the immediate need to identify/develop new sources of TriMV resistance to effectively manage the recurring WSM epidemic.

Immune protection induced by E2 recombinant glycoprotein of bovine viral diarrhea virus in a murine model.

Bovine viral diarrhea virus (BVDV) is considered the most important viral pathogen in ruminants worldwide due to the broad range of clinical manifestations displayed by infected animals. Therefore, infection with BVDV leads to severe economic losses in several countries' beef and dairy industries. Vaccination prevents reproductive failure and gastrointestinal and respiratory disorders caused by BVDV infection. However, considering their limitations, conventional vaccines such as live, attenuated, and killed viruses have been applied. Hence, different studies have described subunit vaccines as an effective and safe alternative for BVDV protection. Therefore, in this study, the ectodomain of E2 (E2e) glycoprotein from NADL BVDV strain was expressed in mammalian cells and used in two vaccine formulations to evaluate immunogenicity and protection against BVDV conferred in a murine model. Formulations consisted of solo E2e glycoprotein and E2e glycoprotein emulsified in adjuvant ISA 61 VG. Five groups of 6 mice of 6-to-8-week-old were immunized thrice on days 1, 15, and 30 by intraperitoneal injection with the mentioned formulations and controls. To evaluate the conferred protection against BVDV, mice were challenged six weeks after the third immunization. In addition, the humoral immune response was evaluated after vaccination and challenge. Mice groups inoculated with solo E2e and the E2e + ISA 61 VG displayed neutralizing titers; however, the E2 antibody titers in the E2e + ISA 61 VG group were significantly higher than the mice group immunized with the solo E2e glycoprotein. In addition, immunization using E2e + ISA 61 VG prevents animals from developing severe lesions in surveyed tissues. Moreover, this group acquired protection against the BVDV challenge, evidenced by a significant reduction of positive staining for BVDV antigen in the lungs, liver, and brain between the experimental groups. Our findings demonstrated that using E2e + ISA 61 VG induces greater BVDV protection by an early humoral response and reduced histopathological lesions and BVDV antigen detection in affected organs, indicating that E2e + ISA 61 VG subunit formulation can be considered as a putative vaccine candidate against BVDV. The efficacy and safety of this vaccine candidate in cattle requires further investigation.

Watermelon mosaic virus in the Czech Republic, its recent and historical origins

AbstractWatermelon mosaic virus (WMV) is a potyvirus and a member of the bean common mosaic virus (BCMV) lineage. It is one of the most economically important viral pathogens of cucurbits worldwide and was first reported in the Czech Republic in 2011 from serological surveys (2005–2011). In this study, we confirmed this identification by determining the complete coding regions of five Czech WMV isolates using high‐throughput sequencing and Sanger sequencing (MW188031; OP585149–OP585152), together with the coat protein (CP) genes of 26 additional isolates. Phylogenies were made from these and more than 128 genomes or 128 CP genes from GenBank. They showed that the Czech isolates were most closely related to other European isolates, but, surprisingly, 96.2% of the genomes were recombinant. The nonrecombinant sequences mostly came from basal isolates, all originating from China, and some from unusual hosts (Ailanthus altissima, Alcea rosea and Panax ginseng). The complete WMV genomes form three phylogenetic clades, two of them small and basal, and the third includes all other isolates. Comparative dating suggests that the basal Chinese isolates are descendants of a potyvirus population infecting various dicotyledonous plant species in China at least 2000 years ago. WMV became a crop pathogen around 1000 years ago, a few years after watermelon was taken to northern China and first grown as a crop during the Five Dynasties (907–960 ce).

Simultaneous and rapid detection of avian respiratory diseases of small poultry using multiplex reverse transcription-Polymerase Chain Reaction assay

Major viral infections, such as Newcastle disease virus, infectious bronchitis virus, avian influenza virus, and infectious bursal disease virus, inflict significant injury to small poultry and tremendous economic damage to the poultry sector. This research aims to develop a multiplex reverse transcriptase polymerase chain reaction (m-RT-PCR) approach to simultaneously determine these important viral pathogens. The conserved segment of various viral genetic sequences was used to design and synthesize specific primers. Moreover, as positive controls, recombinant vectors were synthesized in this investigation. The d-optimal approach was used to improve PCR conditions in this investigation. Positive controls and clinical samples were used to assess the m-PCR assay's specificity, sensitivity, repeatability, and reproducibility. According to the sensitivity test findings, the m-PCR technique could generate the 8 target genes from viral genomes using 1×102. In addition, 8 viral pathogens were detected from the infected samples. The findings also suggest that live animal oral swabs were not significantly different from tissue sampling of a dead animal (P < 0.05), and this kit had a high sensitivity for analyzing both types of samples. The suggested m-PCR test may detect and evaluate viral infection in birds with excellent specificity, sensitivity, and throughput.