Occurrence and Distribution of Major Viruses Infecting Eggplant in Lebanon and Molecular Characterization of a Local Potato Virus X Isolate

This research was carried out in order to evaluate the presence and distribution of viral infections causing severe disease in eggplant plants collected from different districts in Bekaa valley, Lebanon. Most infected plants showed virus-like symptoms consisting predominantly of leaf blotch, mottling chlorotic and ring spots; leaf twisting and plant dwarf were also observed in the visited fields. Symptomatic and asymptomatic plants were collected and screened by ELISA test for the presence of several different pathogenic viruses potentially present in the area. Results showed that potato virus Y (PVY) was the most prevalent virus found by ELISA (detected in the 15.3% of the tested plants), followed by eggplant mottled dwarf virus (EMDV, 2.9%) and cucumber mosaic virus (CMV, 1.2%), while tomato spotted wilt virus (TSWV), alfalfa mosaic virus (AMV) and pepper mottle virus (PepMoV) were not detected. Biological indexing of symptomatic ELISA-negative plants, followed by electron microscopy, indicated the presence of virus-like particles of the genus Potexvirus, which was subsequently confirmed as potato virus X (PVX) by RT-PCR and Sanger sequencing. PVX was found in 35.3% of the tested plants, all sampled in the northern Bekaa area. In a phylogenetic analysis, the partial coat protein gene sequence of a selected Lebanese isolate, PVX-AK1, clustered together with other PVX isolates from Asia. Furthermore, the 124-aa sequence of PVX-AK1 shared 100% identity with PVX-UK3, an isolate which is known as avirulent in potato genotypes carrying either Nx or Rx resistance genes. This work revealed a picture of the previously uninvestigated phytosanitary status of eggplant crops in an important horticultural area of Lebanon.

Genomic and phylogenetic analyses of SARS-CoV-2 strains isolated in the city of Gwangju, South Korea

Since the first identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China in late December 2019, the coronavirus disease 2019 (COVID-19) has spread fast around the world. RNA viruses, including SARS-CoV-2, have higher gene mutations than DNA viruses during virus replication. Variations in SARS-CoV-2 genome could contribute to efficiency of viral spread and severity of COVID-19. In this study, we analyzed the locations of genomic mutations to investigate the genetic diversity among isolates of SARS-CoV-2 in Gwangju. We detected non-synonymous and frameshift mutations in various parts of SARS-CoV-2 genome. The phylogenetic analysis for whole genome showed that SARS-CoV-2 genomes in Gwangju isolates are clustered within clade V and G. Our findings not only provide a glimpse into changes of prevalent virus clades in Gwangju, South Korea, but also support genomic surveillance of SARS-CoV-2 to aid in the development of efficient therapeutic antibodies and vaccines against COVID-19.

DWV infection and replication at the early stage in vitro using honey bee pupal cells

Deformed wing virus (DWV) has been best characterized among honey bee viruses; however, very little is known about the mechanisms of viral infection and replication due to the lack of honey bee cell lines. To resolve this problem, we established in vitro system to reconstitute DWV binding and entry to the host cell followed by translation of the genome RNA and the polyprotein processing with honey bee pupal cells. Using this system, P-domain of VP1 was found to be essential for DWV infection/replication but not binding/entry to the cell. DWV efficiently infects/replicates in cells derived from early but not late pupa, suggesting that the undifferentiated cells are targeted for the viral infection/replication. Furthermore, we found that inhibitors for mammalian picornavirus 3C-Protease, Rupintrivir and Quercetin suppress DWV infection/replication, indicating that this in vitro system is also useful for screening a compound to modify the viral infection/replication. Our in vitro system should help to understand the mechanisms of DWV infection and replication at the early stage.ImportanceRecent decline of managed honey bee colonies has been driven by the pathogens and parasites. However, studying the mechanisms of pathogen infection and replication in honey bee at molecular and cellular levels has been challenging. DWV is the most prevalent virus in honey bee across the globe and we established in vitro system to reconstitute the viral infection and replication with the primary pupal cells. Using RNA-dependent RNA polymerase (RdRP) and the negative strand of DWV genome RNA as markers, we show that the pupal cells can support DWV infection and at least replication at the early stage. The results shown in this report indicate that our in vitro system helps to uncover the mechanisms of DWV infection and replication. Furthermore, it is also feasible to conduct a large scale screening for compounds to inhibit or stimulate DWV infection/replication.

Merkel cell carcinoma: a case report and literature review

Merkel cell carcinoma (MCC) is an aggressive cutaneous malignancy of neuroendocrine origin presenting as a painless, rapidly growing nodule. MCC often presents in elderly, fair-skinned individuals in sun-exposed areas. Diagnosis is often overlooked at time of presentation due to its rarity, but MCC is twice as deadly as malignant melanoma. There has been bigger interest in the disease due to increasing incidence and an association with the prevalent virus Merkel cell polyomavirus. This study describes an uncommon presentation of MCC as a right gluteal lesion in an Afro-Panamanian patient. The tumor was suspected to be fibrolipoma, but Immunohistochemistry revealed the diagnosis of MCC, as stains for CD56 and CK20 were positive. In addition to surgical excision, the patient was referred for adjuvant radiotherapy. This case report and literature review elucidates the clinical, histopathologic and management aspects of MCC, which will help in recognizing and treating these tumors.

Deformed Wing Virus in Honeybees and Other Insects

Deformed wing virus (DWV) has become the most well-known, widespread, and intensively studied insect pathogen in the world. Although DWV was previously present in honeybee populations, the arrival and global spread of a new vector, the ectoparasitic mite Varroa destructor, has dramatically altered DWV epidemiology. DWV is now the most prevalent virus in honeybees, with a minimum average of 55% of colonies/apiaries infected across 32 countries. Additionally, DWV has been detected in 65 arthropod species spanning eight insect orders and three orders of Arachnida. Here, we describe the significant progress that has been made in elucidating the capsid structure of the virus, understanding its ever-expanding host range, and tracking the constantly evolving DWV genome and formation of recombinants. The construction of molecular clones, working with DWV in cell lines, and the development of immunohistochemistry methods will all help the community to move forward. Identifying the tissues in which DWV variants are replicating and understanding the impact of DWV in non-honeybee hosts are major new goals.

Viral and Bacterial Etiologies of Acute Respiratory Infections Among Children Under 5 Years in Senegal

Acute respiratory infections (ARIs) are the leading cause of infectious disease–related morbidity, hospitalization, and morbidity among children worldwide. This study aimed to assess the viral and bacterial causes of ARI morbidity and mortality in children under 5 years in Senegal. Nasopharyngeal samples were collected from children under 5 years who had ARI. Viruses and bacteria were identified using multiplex real-time reverse transcription-polymerase chain reaction and conventional biochemical techniques, respectively. Adenovirus was the most prevalent virus (50%; n = 81), followed by influenza virus (45.68%, n = 74), rhinovirus (40.12%; n = 65), enterovirus (25.31%; n = 41), and respiratory syncytial virus (16.05%; n = 26), whereas Streptococcus pneumoniae (17%; n = 29), Moraxella catarrhalis (15.43%; n = 25), and Haemophilus influenzae (8.02%; n = 13) were the most commonly isolated bacteria. Virus pathogens seem more likely to be more prevalent in our settings and were often associated with bacteria and S. pneumoniae (6%; 16) coinfection.

Presencia del marcador lmp-1 del virus epstein barr en linfomas de caninos

Epstein Barr virus (EBV) is a humans’ high prevalent virus associated with lymphoid B cells tumors development. In canines, few reports have been published regarding the presence of the virus in dogs but its role in this species remain unclear. The aim of this study was to determine the presence of LMP-1 protein of EBV in 20 canine lymphomas tissues which were previously diagnosed in a period of time between 2004 -2014. Lymphomas were reclassified in accordance with the new histopathological classifications for lymphomas and were stained by IHQ with anti-CD79a, anti-CD3 and anti-LMP1; specific antibodies for B lymphocytes, T lymphocytes and EBV biomarker respectively. As a result, it was found that the most common lymphoma was T-zone lymphoma in 75% of the cases of the study. The distribution of the cases regarding the immunostaining were: 18 positive cases with anti- CD3, 2 positive cases with anti-CD79a and 6 positive cases with anti-LMP-1. Positive cases of LMP1 as a biomarker of the presence of EBV corresponded to the 30% of the cases of the study. Chi-square test showed statistical significance between the presence of the virus and the presence of lymphomas, which suggests not only that the virus is circulating in the canine population but also that could have implications in the development of the disease. Regarding demographic parameters, only the Golden Retriever breed showed a relationship with the presence of lymphoma, but not with the presence of the virus.

Lack of association between viral load and severity of acute bronchiolitis in infants

ABSTRACT Objective: To investigate the correlation between respiratory syncytial viral load and length of hospitalization in infants with acute wheezing episodes. Methods: This was a two-year, cross-sectional study of infants ≤ 12 months of age with bronchiolitis at the time of admission to a tertiary hospital. For the identification of respiratory viruses, nasopharyngeal secretions were collected. Samples were analyzed (throughout the study period) by direct immunofluorescence and (in the second year of the study) by quantitative real-time PCR. We screened for three human viruses: rhinovirus, respiratory syncytial virus, and metapneumovirus. Results: Of 110 samples evaluated by direct immunofluorescence, 56 (50.9%) were positive for a single virus, and 16 (14.5%) were positive for two or more viruses. Among those 72 samples, the most prevalent virus was respiratory syncytial virus, followed by influenza. Of 56 samples evaluated by quantitative real-time PCR, 24 (42.8%) were positive for a single virus, and 1 (1.7%) was positive for two viruses. Among those 25 samples, the most prevalent virus was again respiratory syncytial virus, followed by human rhinovirus. Coinfection did not influence the length of the hospital stay or other outcome s. In addition, there was no association between respiratory syncytial virus load and the length of hospitalization. Conclusions: Neither coinfection nor respiratory syncytial viral load appears to influence the outcomes of acute bronchiolitis in infants.

Occurrence and molecular analysis of quarantine virus in lily cultivation areas in Brazil

The objective of this work was to describe the occurrence of quarantine Tulip breaking virus (TBV, synonym Lily mottle virus - LMoV) and Lily symptomless virus (LSV), and their respective molecular analyses, to provide data for supporting TBV removal from the Brazilian A1 quarantine pest list, since this virus has spread among the main commercial lily crops in Brazil. The occurrence of these viruses was detected in 12 cultivation areas through multiplex reverse transcription (RT-PCR), using specific primers to genes encoding the respective coat proteins (CP). Eight fragments of 800 nucleotides (nt) obtained from the LMoV-infected lilies and nine fragments of 600 nt from LSV-infected lilies were sequenced. Phylogenetic tree reconstruction showed a robust branch containing the LMoV Brazilian sequences, other LMoV isolates, TBV, and Tulip band breaking virus, suggesting that all are LMoV isolates, although they are clustered into two subgroups. Phylogenetic analysis also showed a robust branch supporting all Brazilian and other LSV sequences, except for an LSV Japanese isolate. Recombination analyses also showed an LMoV recombinant isolate, whereas no recombination events were found among LSV isolates. Lily mottle virus is the prevalent virus in lily crops in Brazil, in single and mixed infections with LSV or Cucumber mosaic virus (CMV).