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1.
Virol J ; 18(1): 177, 2021 08 28.
Article in English | MEDLINE | ID: covidwho-1767103

ABSTRACT

BACKGROUND: The development of an influenza RNA-dependent RNA polymerase (RdRp) inhibitor is required; therefore, a method for evaluating the activity of influenza RdRp needs to be developed. The current method uses an ultracentrifuge to separate viral particles and quantifies RdRp activity with radioisotope-labeled nucleosides, such as 32P-GTP. This method requires special equipment and radioisotope management, so it cannot be implemented in all institutions. We have developed a method to evaluate the mRNA transcription activity of RdRp without using ultracentrifugation and radioisotopes. RESULTS: RdRp was extracted from viral particles that were purified from the culture supernatant using anionic polymer-coated magnetic beads that can concentrate influenza virus particles from the culture supernatant in approximately 30 min. A strand-specific real-time reverse transcription polymerase chain reaction (RT-PCR) method was developed based on reverse transcription using tagged primers. RT primers were designed to bind to a sequence near the 3' end of mRNA containing a poly A tail for specific recognition of the mRNA, with an 18-nucleotide tag attached to the 5' end of the sequence. The RT reaction was performed with this tagged RT primer, and the amount of mRNA was analyzed using real-time qPCR. Real-time qPCR using the tag sequence as the forward primer and a segment-specific reverse primer ensured the specificity for quantifying the mRNA of segments 1, 4, and 5. The temperature, reaction time, and Mg2+ concentration were determined to select the optimum conditions for in vitro RNA synthesis by RdRp, and the amount of synthesized mRNAs of segments 1, 4, and 5 was determined with a detection sensitivity of 10 copies/reaction. In addition, mRNA synthesis was inhibited by ribavirin triphosphate, an RdRp inhibitor, thus indicating the usefulness of this evaluation method for screening RdRp inhibitors. CONCLUSION: This method makes it possible to analyze the RdRp activity even in a laboratory where ultracentrifugation and radioisotopes cannot be used. This novel method for measuring influenza virus polymerase activity will further promote research to identify compounds that inhibit viral mRNA transcription activity of RdRp.


Subject(s)
Influenza, Human , Orthomyxoviridae , RNA-Dependent RNA Polymerase , Reverse Transcription , Humans , Orthomyxoviridae/genetics , RNA, Messenger/genetics , RNA, Viral/genetics , RNA-Dependent RNA Polymerase/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction
2.
Viruses ; 14(3)2022 03 03.
Article in English | MEDLINE | ID: covidwho-1767152

ABSTRACT

Influenza virus transcription is catalyzed by the viral RNA-polymerase (FluPol) through a cap-snatching activity. The snatching of the cap of cellular mRNA by FluPol is preceded by its binding to the flexible C-terminal domain (CTD) of the RPB1 subunit of RNA-polymerase II (Pol II). To better understand how FluPol brings the 3'-end of the genomic RNAs in close proximity to the host-derived primer, we hypothesized that FluPol may recognize additional Pol II subunits/domains to ensure cap-snatching. Using binary complementation assays between the Pol II and influenza A FluPol subunits and their structural domains, we revealed an interaction between the N-third domain of PB2 and RPB4. This interaction was confirmed by a co-immunoprecipitation assay and was found to occur with the homologous domains of influenza B and C FluPols. The N-half domain of RPB4 was found to be critical in this interaction. Punctual mutants generated at conserved positions between influenza A, B, and C FluPols in the N-third domain of PB2 exhibited strong transcriptional activity defects. These results suggest that FluPol interacts with several domains of Pol II (the CTD to bind Pol II), initiating host transcription and a second transcription on RPB4 to locate FluPol at the proximity of the 5'-end of nascent host mRNA.


Subject(s)
Influenza, Human , Orthomyxoviridae , Humans , Orthomyxoviridae/genetics , RNA Polymerase II/metabolism , RNA, Messenger/genetics , RNA, Viral/genetics , RNA, Viral/metabolism , RNA-Dependent RNA Polymerase/genetics , Viral Transcription , Virus Replication
3.
Sci Rep ; 12(1): 4947, 2022 03 23.
Article in English | MEDLINE | ID: covidwho-1758377

ABSTRACT

The COVID-19 pandemic required increased testing capacity, enabling rapid case identification and effective contract tracing to reduce transmission of disease. The BioFire FilmArray is a fully automated nucleic acid amplification test system providing specificity and sensitivity associated with gold standard molecular methods. The FilmArray Respiratory Panel 2.1 targets 22 viral and bacterial pathogens, including SARS-CoV-2 and influenza virus. While each panel provides a robust output of information regarding pathogen detection, the specimen throughput is low. This study evaluates the FilmArray Respiratory Panel 2.1 using 33 pools of contrived nasal samples and 22 pools of clinical nasopharyngeal specimens to determine the feasibility of increasing testing capacity, while maintaining detection of both SARS-CoV-2 and influenza virus. We observed 100% detection and 90% positive agreement for SARS-CoV-2 and 98% detection and 95% positive agreement for influenza viruses with pools of contrived or clinical specimens, respectively. While discordant results were mainly attributed to loss in sensitivity, the sensitivity of the pooling assay was well within accepted limits of detection for a nucleic acid amplification test. Overall, this study provides evidence supporting the use of pooling patient specimens, one in four with the FilmArray Respiratory Panel 2.1 for the detection of SARS-CoV-2 and influenza virus.


Subject(s)
COVID-19 , Orthomyxoviridae , Respiratory Tract Infections , COVID-19/diagnosis , Humans , Molecular Diagnostic Techniques/methods , Orthomyxoviridae/genetics , Pandemics , SARS-CoV-2/genetics
4.
PLoS One ; 17(3): e0264949, 2022.
Article in English | MEDLINE | ID: covidwho-1742012

ABSTRACT

BACKGROUND: In the context of COVID-19 pandemic in Catalonia (Spain), the present study analyses respiratory samples collected by the primary care network using Acute Respiratory Infections Sentinel Surveillance System (PIDIRAC) during the 2019-2020 season to complement the pandemic surveillance system in place to detect SARS-CoV-2. The aim of the study is to describe whether SARS-CoV-2 was circulating before the first confirmed case was detected in Catalonia, on February 25th, 2020. METHODS: The study sample was made up of all samples collected by the PIDIRAC primary care network as part of the Influenza and Acute Respiratory Infections (ARI) surveillance system activities. The study on respiratory virus included coronavirus using multiple RT-PCR assays. All positive samples for human coronavirus were subsequently typed for HKU1, OC43, NL63, 229E. Every respiratory sample was frozen at-80°C and retrospectively studied for SARS-CoV-2 detection. A descriptive study was performed, analysing significant differences among variables related to SARS-CoV- 2 cases comparing with rest of coronaviruses cases through a bivariate study with Chi-squared test and statistical significance at 95%. RESULTS: Between October 2019 and April 2020, 878 respiratory samples from patients with acute respiratory infection or influenza syndrome obtained by PIDIRAC were analysed. 51.9% tested positive for influenza virus, 48.1% for other respiratory viruses. SARS-CoV-2 was present in 6 samples. The first positive SARS-CoV-2 case had symptom onset on 2 March 2020. These 6 cases were 3 men and 3 women, aged between 25 and 50 years old. 67% had risk factors, none had previous travel history nor presented viral coinfection. All of them recovered favourably. CONCLUSION: Sentinel Surveillance PIDIRAC enhances global epidemiological surveillance by allowing confirmation of viral circulation and describes the epidemiology of generalized community respiratory viruses' transmission in Catalonia. The system can provide an alert signal when identification of a virus is not achieved in order to take adequate preparedness measures.


Subject(s)
COVID-19/diagnosis , Coronavirus/classification , Orthomyxoviridae/classification , RNA, Viral/genetics , Respiratory Tract Infections/virology , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/epidemiology , Child , Child, Preschool , Coronavirus/genetics , Coronavirus/isolation & purification , Female , Humans , Infant , Male , Middle Aged , Orthomyxoviridae/genetics , Orthomyxoviridae/isolation & purification , Primary Health Care , Retrospective Studies , Sentinel Surveillance , Spain/epidemiology , Young Adult
5.
PLoS One ; 17(3): e0264855, 2022.
Article in English | MEDLINE | ID: covidwho-1736511

ABSTRACT

Since December 2019 the world has been facing the outbreak of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Identification of infected patients and discrimination from other respiratory infections have so far been accomplished by using highly specific real-time PCRs. Here we present a rapid multiplex approach (RespiCoV), combining highly multiplexed PCRs and MinION sequencing suitable for the simultaneous screening for 41 viral and five bacterial agents related to respiratory tract infections, including the human coronaviruses NL63, HKU1, OC43, 229E, Middle East respiratory syndrome coronavirus, SARS-CoV, and SARS-CoV-2. RespiCoV was applied to 150 patient samples with suspected SARS-CoV-2 infection and compared with specific real-time PCR. Additionally, several respiratory tract pathogens were identified in samples tested positive or negative for SARS-CoV-2. Finally, RespiCoV was experimentally compared to the commercial RespiFinder 2SMART multiplex screening assay (PathoFinder, The Netherlands).


Subject(s)
Bacteria/genetics , COVID-19/diagnosis , High-Throughput Nucleotide Sequencing/methods , RNA Viruses/genetics , Respiratory Tract Infections/diagnosis , SARS-CoV-2/genetics , Bacteria/isolation & purification , COVID-19/virology , Coronavirus/genetics , Coronavirus/isolation & purification , DNA, Bacterial/chemistry , DNA, Bacterial/metabolism , Herpesvirus 1, Human/genetics , Herpesvirus 1, Human/isolation & purification , Humans , Multiplex Polymerase Chain Reaction , Nanopores , Orthomyxoviridae/genetics , Orthomyxoviridae/isolation & purification , RNA Viruses/isolation & purification , RNA, Viral/chemistry , RNA, Viral/metabolism , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/virology , SARS-CoV-2/isolation & purification
7.
Epidemiol Infect ; 149: e226, 2021 10 26.
Article in English | MEDLINE | ID: covidwho-1537267

ABSTRACT

The corona virus disease-2019 (COVID-19) pandemic began in Wuhan, China, and quickly spread around the world. The pandemic overlapped with two consecutive influenza seasons (2019/2020 and 2020/2021). This provided the opportunity to study community circulation of influenza viruses and severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in outpatients with acute respiratory infections during these two seasons within the Bavarian Influenza Sentinel (BIS) in Bavaria, Germany. From September to March, oropharyngeal swabs collected at BIS were analysed for influenza viruses and SARS-CoV-2 by real-time polymerase chain reaction. In BIS 2019/2020, 1376 swabs were tested for influenza viruses. The average positive rate was 37.6%, with a maximum of over 60% (in January). The predominant influenza viruses were Influenza A(H1N1)pdm09 (n = 202), Influenza A(H3N2) (n = 144) and Influenza B Victoria lineage (n = 129). In all, 610 of these BIS swabs contained sufficient material to retrospectively test for SARS-CoV-2. SARS-CoV-2 RNA was not detectable in any of these swabs. In BIS 2020/2021, 470 swabs were tested for influenza viruses and 457 for SARS-CoV-2. Only three swabs (0.6%) were positive for Influenza, while SARS-CoV-2 was found in 30 swabs (6.6%). We showed that no circulation of SARS-CoV-2 was detectable in BIS during the 2019/2020 influenza season, while virtually no influenza viruses were found in BIS 2020/2021 during the COVID-19 pandemic.


Subject(s)
COVID-19/epidemiology , Influenza, Human/epidemiology , Sentinel Surveillance , COVID-19/diagnosis , Germany/epidemiology , Humans , Incidence , Influenza, Human/diagnosis , Oropharynx/virology , Orthomyxoviridae/classification , Orthomyxoviridae/genetics , Orthomyxoviridae/isolation & purification , RNA, Viral/genetics , Retrospective Studies , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Seasons
8.
Elife ; 102021 10 18.
Article in English | MEDLINE | ID: covidwho-1485452

ABSTRACT

The repeated emergence of similar variants of influenza virus is linked to interactions between the virus's RNA segments.


Subject(s)
Influenza, Human , Orthomyxoviridae , Evolution, Molecular , Humans , Influenza, Human/epidemiology , Orthomyxoviridae/genetics
9.
Med Microbiol Immunol ; 210(5-6): 277-282, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1449965

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has forced the implementation of unprecedented public health measures strategies which might also have a significant impact on the spreading of other viral pathogens such as influenza and Respiratory Syncytial Virus (RSV) . The present study compares the incidences of the most relevant respiratory viruses before and during the SARS-CoV-2 pandemic in emergency room patients. We analyzed the results of in total 14,946 polymerase chain reaction point-of-care tests (POCT-PCR) for Influenza A, Influenza B, RSV and SARS-CoV-2 in an adult and a pediatric emergency room between December 1, 2018 and March 31, 2021. Despite a fivefold increase in the number of tests performed, the positivity rate for Influenza A dropped from 19.32% (165 positives of 854 tests in 2018/19), 14.57% (149 positives of 1023 in 2019-20) to 0% (0 positives of 4915 tests) in 2020/21. In analogy, the positivity rate for Influenza B and RSV dropped from 0.35 to 1.47%, respectively, 10.65-21.08% to 0% for both in 2020/21. The positivity rate for SARS-CoV2 reached 9.74% (110 of 1129 tests performed) during the so-called second wave in December 2020. Compared to the two previous years, seasonal influenza and RSV incidence was eliminated during the COVID-19 pandemic. Corona-related measures and human behavior patterns could lead to a significant decline or even complete suppression of other respiratory viruses such as influenza and RSV.


Subject(s)
COVID-19/epidemiology , Influenza, Human/diagnosis , Point-of-Care Testing/statistics & numerical data , Respiratory Syncytial Virus Infections/diagnosis , COVID-19/virology , Hospitals/statistics & numerical data , Humans , Incidence , Influenza, Human/epidemiology , Influenza, Human/virology , Orthomyxoviridae/genetics , Orthomyxoviridae/isolation & purification , Orthomyxoviridae/physiology , Pandemics , Polymerase Chain Reaction , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human/genetics , Respiratory Syncytial Virus, Human/isolation & purification , Respiratory Syncytial Virus, Human/physiology , Retrospective Studies
10.
Chem Pharm Bull (Tokyo) ; 69(10): 984-988, 2021.
Article in English | MEDLINE | ID: covidwho-1445702

ABSTRACT

Membrane-based rapid test reagents including immunochromatography are widely used in clinical practice. Recently, high-sensitive reagents based on the immunochromatography method, such as silver amplification method and time resolved fluorescence method for influenza testing, has been developed and early confirmation of infection can be achieved. Furthermore, genetic testing, automated all the steps from extraction till detection, is getting popular. Genetic testing of mycoplasma by Smart Gene Myco system and Coronavirus disease 2019 (COVID-19) test is a good example of membrane-based rapid test reagents. This system uses silica particle-containing membrane filter and enable to shorten the assay time by automates pre-treatment process for removing contamination substances in the sample which affect polymerase-chain-reaction amplification. We hope utilized genetic testing application will help quick confirmation of COVID-19 positive patient and prevent the collapse of medical system under COVID-19 development.


Subject(s)
Chromatography, Affinity/methods , Point-of-Care Systems , COVID-19/diagnosis , COVID-19/virology , COVID-19 Testing , Genetic Testing , Humans , Influenza, Human/diagnosis , Influenza, Human/virology , Orthomyxoviridae/genetics , Orthomyxoviridae/isolation & purification , Polymerase Chain Reaction , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification
11.
Cell Mol Life Sci ; 78(21-22): 6735-6744, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1377320

ABSTRACT

Kallikrein-related peptidases (KLKs) or kallikreins have been linked to diverse (patho) physiological processes, such as the epidermal desquamation and inflammation, seminal clot liquefaction, neurodegeneration, and cancer. Recent mounting evidence suggests that KLKs also represent important regulators of viral infections. It is well-established that certain enveloped viruses, including influenza and coronaviruses, require proteolytic processing of their hemagglutinin or spike proteins, respectively, to infect host cells. Similarly, the capsid protein of the non-enveloped papillomavirus L1 should be proteolytically cleaved for viral uncoating. Consequently, extracellular or membrane-bound proteases of the host cells are instrumental for viral infections and represent potential targets for drug development. Here, we summarize how extracellular proteolysis mediated by the kallikreins is implicated in the process of influenza (and potentially coronavirus and papillomavirus) entry into host cells. Besides direct proteolytic activation of viruses, KLK5 and 12 promote viral entry indirectly through proteolytic cascade events, like the activation of thrombolytic enzymes that also can process hemagglutinin, while additional functions of KLKs in infection cannot be excluded. In the light of recent evidence, KLKs represent potential host targets for the development of new antivirals. Humanized animal models to validate their key functions in viral infections will be valuable.


Subject(s)
COVID-19/enzymology , COVID-19/virology , Host Microbial Interactions/physiology , Kallikreins/metabolism , SARS-CoV-2 , Virus Diseases/enzymology , Animals , Asthma/etiology , Coronavirus/genetics , Coronavirus/pathogenicity , Coronavirus/physiology , Host Microbial Interactions/genetics , Humans , Orthomyxoviridae/genetics , Orthomyxoviridae/pathogenicity , Orthomyxoviridae/physiology , Papillomavirus Infections/enzymology , Papillomavirus Infections/virology , Picornaviridae Infections/complications , Picornaviridae Infections/enzymology , Picornaviridae Infections/virology , Protein Processing, Post-Translational , Proteolysis , Rhinovirus/pathogenicity , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity , SARS-CoV-2/physiology , Varicella Zoster Virus Infection/enzymology , Varicella Zoster Virus Infection/virology , Viral Proteins/genetics , Viral Proteins/metabolism , Virus Diseases/virology , Virus Internalization
13.
Viruses ; 13(6)2021 06 05.
Article in English | MEDLINE | ID: covidwho-1259626

ABSTRACT

Epithelial characteristics underlying the differential susceptibility of chronic asthma to SARS-CoV-2 (COVID-19) and other viral infections are currently unclear. By revisiting transcriptomic data from patients with Th2 low versus Th2 high asthma, as well as mild, moderate, and severe asthmatics, we characterized the changes in expression of human coronavirus and influenza viral entry genes relative to sex, airway location, and disease endotype. We found sexual dimorphism in the expression of SARS-CoV-2-related genes ACE2, TMPRSS2, TMPRSS4, and SLC6A19. ACE2 receptor downregulation occurred specifically in females in Th2 high asthma, while proteases broadly assisting coronavirus and influenza viral entry, TMPRSS2, and TMPRSS4, were highly upregulated in both sexes. Overall, changes in SARS-CoV-2-related gene expression were specific to the Th2 high molecular endotype of asthma and different by asthma severity and airway location. The downregulation of ACE2 (COVID-19, SARS) and ANPEP (HCoV-229E) viral receptors wascorrelated with loss of club and ciliated cells in Th2 high asthma. Meanwhile, the increase in DPP4 (MERS-CoV), ST3GAL4, and ST6GAL1 (influenza) was associated with increased goblet and basal activated cells. Overall, this study elucidates sex, airway location, disease endotype, and changes in epithelial heterogeneity as potential factors underlying asthmatic susceptibility, or lack thereof, to SARS-CoV-2.


Subject(s)
Asthma/immunology , COVID-19/immunology , Coronavirus Infections/immunology , Epithelial Cells/virology , Gene Expression , Host Microbial Interactions , Influenza, Human/immunology , Severity of Illness Index , Asthma/genetics , Asthma/virology , COVID-19/genetics , Coronavirus 229E, Human/genetics , Coronavirus 229E, Human/immunology , Coronavirus Infections/genetics , Epithelial Cells/classification , Female , Gene Expression Profiling , Host Microbial Interactions/genetics , Host Microbial Interactions/immunology , Humans , Influenza, Human/genetics , Male , Middle East Respiratory Syndrome Coronavirus/genetics , Middle East Respiratory Syndrome Coronavirus/immunology , Orthomyxoviridae/genetics , Orthomyxoviridae/immunology , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Sex Characteristics
15.
Viruses ; 13(5)2021 04 25.
Article in English | MEDLINE | ID: covidwho-1202422

ABSTRACT

Some of the newly emerging corona viral variants show high numbers of mutations. This is unexpected for a virus with a low mutation rate due to an inherent proof-reading system. Could such a variant arise under very special conditions occurring in a host where the virus replicates and mutates in a rather unlimited fashion, such as in immune compromised patients? The virus was shown to replicate in an immunosuppressed cancer patient for more than 105 days and might be a source of new variants. These patients are asymptomatic and the virus may therefore escape detection and attention and be high-risk. Similarly, HIV-infected individuals may be immunocompromised and support coronavirus replication with increased mutation rates. The patients may promote "within-host evolution". Some of the viruses present in such a highly mutagenic swarm or quasispecies within one patient may become founders and cause a pandemic by further "between-host evolution". B.1.1.7 with 23 mutations may be such a case. Immunosuppressed patients can be identified and treated by the synthetic antibody cocktails as passive immunization and kept under control. Immunosuppressed patients can be easily identified and supervised by healthcare workers-once they become aware of the risk-to avoid new variants with pandemic potential.


Subject(s)
COVID-19/virology , Mutation , SARS-CoV-2/genetics , Brazil , Evolution, Molecular , Genome, Viral , Health Personnel , Host-Pathogen Interactions , Humans , Immunization, Passive , Influenza, Human , Mutagenesis , Mutation Rate , Orthomyxoviridae/genetics , Pandemics , Quasispecies
16.
J Infect Chemother ; 27(6): 820-825, 2021 Jun.
Article in English | MEDLINE | ID: covidwho-1045151

ABSTRACT

INTRODUCTION: Digital immunoassays (DIAs) and molecular point-of-care (POC) tests for influenza were recently developed. We aimed to evaluate and compare the positive rate with molecular POC tests and DIAs in detecting influenza virus A, B and respiratory syncytial virus (RSV). METHODS: A prospective observational study was conducted in 2019-2020. Nasopharyngeal swab samples were collected from adult outpatients with influenza-like illness who visited four hospitals and clinics in Japan. DIAs were performed at each facility. The clinical diagnosis was determined based on the findings of DIAs, history taking, and physical assessment. Molecular POC test and reverse transcription polymerase chain reaction (RT-PCR) were performed later. RESULTS: A total of 182 patients were evaluated. The positive rate for influenza virus with molecular POC test was significantly higher than that with DIAs (51.6% versus 40.7%, p = 0.046). In patients who tested positive for influenza virus with only molecular POC test, the presence of influenza virus was confirmed by RT-PCR. In a comparison between the patients who were positive for influenza virus with only molecular POC test and those with both molecular POC test and DIA, the percentage of patients who sought consultation within 18 h after the onset of symptoms was significantly higher in the molecular POC test only group than in the both methods group (70.0% versus 43.2%, p = 0.044). CONCLUSIONS: A molecular POC test could contribute to the accurate diagnosis of influenza in patients with influenza-like illness, especially those who visited a hospital immediately after the onset of symptoms.


Subject(s)
Influenza A virus , Influenza, Human , Orthomyxoviridae , Respiratory Syncytial Virus Infections , Adult , Humans , Immunoassay , Influenza A virus/genetics , Influenza B virus/genetics , Influenza, Human/diagnosis , Japan , Orthomyxoviridae/genetics , Point-of-Care Systems , Point-of-Care Testing , Respiratory Syncytial Virus Infections/diagnosis , Sensitivity and Specificity
17.
Cells ; 10(3)2021 03 02.
Article in English | MEDLINE | ID: covidwho-1125490

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the coronavirus disease 2019 (COVID-19) that has resulted in the current pandemic. The lack of highly efficacious antiviral drugs that can manage this ongoing global emergency gives urgency to establishing a comprehensive understanding of the molecular pathogenesis of SARS-CoV-2. We characterized the role of the nucleocapsid protein (N) of SARS-CoV-2 in modulating antiviral immunity. Overexpression of SARS-CoV-2 N resulted in the attenuation of retinoic acid inducible gene-I (RIG-I)-like receptor-mediated interferon (IFN) production and IFN-induced gene expression. Similar to the SARS-CoV-1 N protein, SARS-CoV-2 N suppressed the interaction between tripartate motif protein 25 (TRIM25) and RIG-I. Furthermore, SARS-CoV-2 N inhibited polyinosinic: polycytidylic acid [poly(I:C)]-mediated IFN signaling at the level of Tank-binding kinase 1 (TBK1) and interfered with the association between TBK1 and interferon regulatory factor 3 (IRF3), subsequently preventing the nuclear translocation of IRF3. We further found that both type I and III IFN production induced by either the influenza virus lacking the nonstructural protein 1 or the Zika virus were suppressed by the SARS-CoV-2 N protein. Our findings provide insights into the molecular function of the SARS-CoV-2 N protein with respect to counteracting the host antiviral immune response.


Subject(s)
Coronavirus Nucleocapsid Proteins/metabolism , DEAD Box Protein 58/metabolism , Interferons/metabolism , Receptors, Immunologic/metabolism , SARS-CoV-2/metabolism , DEAD Box Protein 58/genetics , Host-Pathogen Interactions/genetics , Humans , Interferon Regulatory Factor-3/genetics , Interferon Regulatory Factor-3/metabolism , Interferon Type I/genetics , Interferon Type I/metabolism , Interferon-gamma/genetics , Interferon-gamma/metabolism , Interferons/genetics , Orthomyxoviridae/genetics , Orthomyxoviridae/metabolism , Phosphoproteins/metabolism , Poly C/pharmacology , Poly I/pharmacology , Promoter Regions, Genetic , /metabolism , Receptors, Immunologic/genetics , SARS-CoV-2/genetics , Signal Transduction/drug effects , Signal Transduction/genetics , Transcription Factors/metabolism , Tripartite Motif Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Up-Regulation , Zika Virus/genetics , Zika Virus/metabolism
18.
Viruses ; 13(3)2021 03 10.
Article in English | MEDLINE | ID: covidwho-1124780

ABSTRACT

BACKGROUND: Both SARS-CoV-2 and influenza virus share similarities such as clinical features and outcome, laboratory, and radiological findings. METHODS: Literature search was done using PubMed to find MEDLINE indexed articles relevant to this study. As of 25 November 2020, the search has been conducted by combining the MeSH words "COVID-19" and "Influenza". RESULTS: Eighteen articles were finally selected in adult patients. Comorbidities such as cardiovascular diseases, diabetes, and obesity were significantly higher in COVID-19 patients, while pulmonary diseases and immunocompromised conditions were significantly more common in influenza patients. The incidence rates of fever, vomiting, ocular and otorhinolaryngological symptoms were found to be significantly higher in influenza patients when compared with COVID-19 patients. However, neurologic symptoms and diarrhea were statistically more frequent in COVID-19 patients. The level of white cell count and procalcitonin was significantly higher in influenza patients, whereas thrombopenia and elevated transaminases were significantly more common in COVID-19 patients. Ground-grass opacities, interlobular septal thickening, and a peripheral distribution were more common in COVID-19 patients than in influenza patients where consolidations and linear opacities were described instead. COVID-19 patients were significantly more often transferred to intensive care unit with a higher rate of mortality. CONCLUSIONS: This study estimated differences of COVID-19 and influenza patients which can help clinicians during the co-circulation of the two viruses.


Subject(s)
COVID-19/virology , Influenza, Human/virology , Orthomyxoviridae/physiology , SARS-CoV-2/physiology , Adolescent , Adult , Aged , COVID-19/diagnostic imaging , COVID-19/mortality , Child , Child, Preschool , Female , Humans , Influenza, Human/diagnostic imaging , Influenza, Human/mortality , Male , Middle Aged , Orthomyxoviridae/genetics , SARS-CoV-2/genetics , Young Adult
19.
J Infect Dis ; 223(5): 765-774, 2021 03 03.
Article in English | MEDLINE | ID: covidwho-1117036

ABSTRACT

BACKGROUND: Pandemic coronavirus disease 2019 (COVID-19) disease represents a challenge for healthcare structures. The molecular confirmation of samples from infected individuals is crucial and therefore guides public health decision making. Clusters and possibly increased diffuse transmission could occur in the context of the next influenza season. For this reason, a diagnostic test able to discriminate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from influenza viruses is urgently needed. METHODS: A multiplex real-time reverse-transcription polymerase chain reaction (PCR) assay was assessed using 1 laboratory protocol with different real-time PCR instruments. Overall, 1000 clinical samples (600 from samples SARS-CoV-2-infected patients, 200 samples from influenza-infected patients, and 200 negative samples) were analyzed. RESULTS: The assay developed was able to detect and discriminate each virus target and to intercept coinfections. The limit of quantification of each assay ranged between 5 and 10 genomic copy numbers, with a cutoff value of 37.7 and 37.8 for influenza and SARS-CoV-2 viruses, respectively. Only 2 influenza coinfections were detected in COVID-19 samples. CONCLUSIONS: This study suggests that multiplex assay is a rapid, valid, and accurate method for the detection of SARS-CoV-2 and influenza viruses in clinical samples. The test may be an important diagnostic tool for both diagnostic and surveillance purposes during the seasonal influenza activity period.


Subject(s)
COVID-19/diagnosis , Influenza, Human/diagnosis , Orthomyxoviridae/isolation & purification , SARS-CoV-2/isolation & purification , Area Under Curve , COVID-19/complications , COVID-19/epidemiology , Diagnosis, Differential , Humans , Influenza, Human/complications , Influenza, Human/epidemiology , Multiplex Polymerase Chain Reaction , Orthomyxoviridae/genetics , RNA, Viral/isolation & purification , ROC Curve , Reproducibility of Results , SARS-CoV-2/genetics , Seasons , Sensitivity and Specificity
20.
PLoS One ; 15(12): e0243735, 2020.
Article in English | MEDLINE | ID: covidwho-1067396

ABSTRACT

INTRODUCTION: Wheezing is a major problem in children, and respiratory viruses are often believed to be the causative agent. While molecular detection tools enable identification of respiratory viruses in wheezing children, it remains unclear if and how these viruses are associated with wheezing. The objective of this systematic review is to clarify the prevalence of different respiratory viruses in children with wheezing. METHODS: We performed an electronic in Pubmed and Global Index Medicus on 01 July 2019 and manual search. We performed search of studies that have detected common respiratory viruses in children ≤18 years with wheezing. We included only studies using polymerase chain reaction (PCR) assays. Study data were extracted and the quality of articles assessed. We conducted sensitivity, subgroup, publication bias, and heterogeneity analyses using a random effects model. RESULTS: The systematic review included 33 studies. Rhinovirus, with a prevalence of 35.6% (95% CI 24.6-47.3, I2 98.4%), and respiratory syncytial virus, at 31.0% (95% CI 19.9-43.3, I2 96.4%), were the most common viruses detected. The prevalence of other respiratory viruses was as follows: human bocavirus 8.1% (95% CI 5.3-11.3, I2 84.6%), human adenovirus 7.7% (95% CI 2.6-15.0, I2 91.0%), influenza virus6.5% (95% CI 2.2-12.6, I2 92.4%), human metapneumovirus5.8% (95% CI 3.4-8.8, I2 89.0%), enterovirus 4.3% (95% CI 0.1-12.9, I2 96.2%), human parainfluenza virus 3.8% (95% CI 1.5-6.9, I2 79.1%), and human coronavirus 2.2% (95% CI 0.6-4.4, I2 79.4%). CONCLUSIONS: Our results suggest that rhinovirus and respiratory syncytial virus may contribute to the etiology of wheezing in children. While the clinical implications of molecular detection of respiratory viruses remains an interesting question, this study helps to illuminate the potential of role respiratory viruses in pediatric wheezing. REVIEW REGISTRATION: PROSPERO, CRD42018115128.


Subject(s)
Respiratory Sounds/etiology , Respiratory Sounds/genetics , Respiratory Tract Infections/diagnosis , Bocavirus/genetics , Bocavirus/isolation & purification , Bocavirus/pathogenicity , Child , Child, Preschool , Coronavirus/isolation & purification , Coronavirus/pathogenicity , Humans , Orthomyxoviridae/genetics , Orthomyxoviridae/isolation & purification , Orthomyxoviridae/pathogenicity , Parainfluenza Virus 1, Human/genetics , Parainfluenza Virus 1, Human/isolation & purification , Parainfluenza Virus 1, Human/pathogenicity , Polymerase Chain Reaction , Respiratory Sounds/physiopathology , Respiratory System/pathology , Respiratory System/virology , Respiratory Tract Infections/genetics , Respiratory Tract Infections/virology
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