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1.
BMC Infect Dis ; 20(1): 913, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261559

RESUMO

BACKGROUND: Influenza B is often perceived as a less severe strain of influenza. The epidemiology and clinical outcomes of influenza B have been less thoroughly investigated in hospitalised patients. The aims of this study were to describe clinical differences and outcomes between influenza A and B patients admitted over a period of 4 years. METHODS: We retrospectively collected data of all laboratory confirmed influenza patients ≥18 years at two tertiary hospitals in South Australia. Patients were confirmed as influenza positive if they had a positive polymerase-chain-reaction (PCR) test of a respiratory specimen. Complications during hospitalisation along with inpatient mortality were compared between influenza A and B. In addition, 30 day mortality and readmissions were compared. Logistic regression model compared outcomes after adjustment for age, Charlson index, sex and creatinine levels. RESULTS: Between January 2016-March 2020, 1846 patients, mean age 66.5 years, were hospitalised for influenza. Of whom, 1630 (88.3%) had influenza A and 216 (11.7%) influenza B. Influenza B patients were significantly younger than influenza A. Influenza A patients were more likely be smokers with a history of chronic obstructive pulmonary disease (COPD) and ischaemic heart disease (IHD) than influenza B. Complications, including pneumonia and acute coronary syndrome (ACS) were similar between two groups, however, septic shock was more common in patients with influenza B. Adjusted analyses showed similar median length of hospital stay (LOS), in hospital mortality, 30-day mortality and readmissions between the two groups. CONCLUSIONS: Influenza B is less prevalent and occurs mostly in younger hospitalised patients than influenza A. Both strains contribute equally to hospitalisation burden and complications. TRIAL REGISTRATION: Australia and New Zealand Clinical Trial Registry (ANZCR) no ACTRN12618000451202 date of registration 28/03/2018.


Assuntos
Vírus da Influenza A/genética , Influenza Humana/epidemiologia , Influenza Humana/mortalidade , Influenzavirus B/genética , Síndrome Coronariana Aguda/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Feminino , Mortalidade Hospitalar , Humanos , Influenza Humana/complicações , Influenza Humana/virologia , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Pneumonia/etiologia , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos
2.
BMC Infect Dis ; 20(1): 910, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261583

RESUMO

BACKGROUND: Both COVID-19 and influenza A contribute to increased mortality among the elderly and those with existing comorbidities. Changes in the underlying immune mechanisms determine patient prognosis. This study aimed to analyze the role of lymphocyte subsets in the immunopathogenesisof COVID-19 and severe influenza A, and examined the clinical significance of their alterations in the prognosis and recovery duration. METHODS: By retrospectively reviewing of patients in four groups (healthy controls, severe influenza A, non-severe COVID-19 and severe COVID-19) who were admitted to Ditan hospital between 2018 to 2020, we performed flow cytometric analysis and compared the absolute counts of leukocytes, lymphocytes, and lymphocyte subsets of the patients at different time points (weeks 1-4). RESULTS: We reviewed the patients' data of 94 healthy blood donors, 80 Non-severe-COVID-19, 19 Severe-COVID-19 and 37 severe influenza A. We found total lymphocytes (0.81 × 109/L vs 1.74 × 109/L, P = 0.001; 0.87 × 109/L vs 1.74 × 109/L, P < 0.0001, respectively) and lymphocyte subsets (T cells, CD4+ and CD8+ T cell subsets) of severe COVID-19 and severe influenza A patients to be significantly lower than those of healthy donors at early infection stages. Further, significant dynamic variations were observed at different time points (weeks 1-4). CONCLUSIONS: Our study suggests the plausible role of lymphocyte subsets in disease progression, which in turn affects prognosis and recovery duration in patients with severe COVID-19 and influenza A.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vírus da Influenza A/genética , Influenza Humana/imunologia , Índice de Gravidade de Doença , Adulto , Idoso , Pequim/epidemiologia , /epidemiologia , Comorbidade , Estudos Transversais , Progressão da Doença , Feminino , Citometria de Fluxo , Humanos , Influenza Humana/epidemiologia , Influenza Humana/virologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
3.
Mol Biol (Mosk) ; 54(6): 968-974, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33276359

RESUMO

The high variability of the influenza A virus poses a significant threat to public health, therefore monitoring viral strains and studying their genetic properties are important tasks. One part of this monitoring includes sequencing of influenza A viruses of any subtype and analysis of their whole genomes, which is especially important in cases of interspecies adaptation and reassortment. High-throughput sequencing technologies have significantly extended the capabilities of influenza virus epidemiological surveillance. The preparation stages for next generation sequencing (NGS) of influenza A virus include whole genome amplification using one-step RT-PCR, the results of which vary greatly depending on the sample type and quality, that, in turn, affects the coverage of virus fragments and the sequencing results in general. In this work, we propose to supplement the aforementioned technique of whole genome amplification of influenza A virus with sequential suppression PCRs to obtain an even coverage of viral segments of different lengths, which allows sequencing of samples with lower read coverage without decreasing the sequencing quality.


Assuntos
Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Vírus da Influenza A , Vírus da Influenza A/genética , Reação em Cadeia da Polimerase
4.
Infez Med ; 28(4): 475-485, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33257621

RESUMO

While the world is focused on attending, controlling, and mitigating the current pandemic of COVID-19, caused by the SARS-CoV-2, other viral threats are possibly emerging and reemerging especially in Asia, posing a risk for the spread in that region and beyond. A predictable threat is the avian influenza virus, especially H5N6, which has recently led to significant outbreaks in China and the Philippines, deserving more attention and control. In the current review, we assess the history of this highly pathogenic reemerging virus, as well as the contemporary implications of poultry outbreaks occurring in some Asian countries. We also look at outbreaks due to other strains not only in Asia but also across Europe and Africa, according to recent reports from the World Organization of Animal Health (OIE).


Assuntos
/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Vírus da Influenza A/classificação , Influenza Humana/epidemiologia , Pandemias , Animais , Doenças Transmissíveis Emergentes/virologia , Humanos , Vírus da Influenza A/genética , Influenza Humana/virologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Aves Domésticas/virologia , /transmissão , /virologia
5.
Acta Virol ; 64(4): 417-426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33151738

RESUMO

Aquatic birds are the main reservoir of influenza A viruses (IAVs). These viruses can infect humans repeatedly and cause acute respiratory disease with potential of spread in the form of epidemics. In addition, avian influenza viruses that overcome the interspecies barrier and adapt to humans can cause a world-wide pandemic with severe consequences to human health. Therefore, scientists are focused on the development of a "universal" vaccine with a broad protective efficacy, i.e. against different subtypes of influenza A viruses and not only against the currently co-circulating human epidemic strains. Nowadays, several new vaccine design strategies have been described. Most of them utilize the conserved stem part of influenza surface glycoprotein hemagglutinin (HA) or the ectodomain of M2 (M2e) protein with proton-channel activity. A comparison of the efficacy of novel vaccines and their protective mechanisms against influenza infection is discussed in this review and should be considered for the construction of the most effective broadly protective vaccine with minimal side effects. This is the essential goal in influenza virus research today, especially when the infection with new human coronavirus SARS-CoV-2 can interfere with the course of influenza virus infection. Keywords: influenza A virus; HA2 gp; M2 ectodomain; universal vaccine.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A , Vacinas contra Influenza/imunologia , Influenza Humana , Proteínas da Matriz Viral/imunologia , Animais , Humanos , Vírus da Influenza A/genética , Influenza Humana/prevenção & controle , Infecções por Orthomyxoviridae
6.
Euro Surveill ; 25(46)2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33213683

RESUMO

The COVID-19 pandemic negatively impacted the 2019/20 WHO European Region influenza surveillance. Compared with previous 4-year averages, antigenic and genetic characterisations decreased by 17% (3,140 vs 2,601) and 24% (4,474 vs 3,403). Of subtyped influenza A viruses, 56% (26,477/47,357) were A(H1)pdm09, 44% (20,880/47,357) A(H3). Of characterised B viruses, 98% (4,585/4,679) were B/Victoria. Considerable numbers of viruses antigenically differed from northern hemisphere vaccine components. In 2020/21, maintaining influenza virological surveillance, while supporting SARS-CoV-2 surveillance is crucial.


Assuntos
Infecções por Coronavirus/epidemiologia , Notificação de Doenças/estatística & dados numéricos , Monitoramento Epidemiológico , Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Antígenos Virais/genética , Betacoronavirus , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza A/genética , Vírus da Influenza B/genética , Pandemias , Pneumonia Viral , Vigilância da População , RNA Viral/genética , Análise de Sequência de DNA
7.
Nat Commun ; 11(1): 5909, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219213

RESUMO

We have surveyed avian influenza virus (AIV) genomes from live poultry markets within China since 2014. Here we present a total of 16,091 samples that were collected from May 2016 to February 2019 in 23 provinces and municipalities in China. We identify 2048 AIV-positive samples and perform next generation sequencing. AIV-positive rates (12.73%) from samples had decreased substantially since 2016, compared to that during 2014-2016 (26.90%). Additionally, H9N2 has replaced H5N6 and H7N9 as the dominant AIV subtype in both chickens and ducks. Notably, novel reassortants and variants continually emerged and disseminated in avian populations, including H7N3, H9N9, H9N6 and H5N6 variants. Importantly, almost all of the H9 AIVs and many H7N9 and H6N2 strains prefer human-type receptors, posing an increased risk for human infections. In summary, our nation-wide surveillance highlights substantial changes in the circulation of AIVs since 2016, which greatly impacts the prevention and control of AIVs in China and worldwide.


Assuntos
Vírus da Influenza A , Influenza Aviária/virologia , Aves Domésticas/virologia , Animais , Aves , Galinhas/virologia , China/epidemiologia , Patos/virologia , Genoma Viral , Humanos , Vírus da Influenza A Subtipo H7N3/genética , Vírus da Influenza A Subtipo H7N3/isolamento & purificação , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/epidemiologia , Influenza Aviária/prevenção & controle , Influenza Humana/virologia , Filogenia , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação
8.
Am J Case Rep ; 21: e926092, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33188162

RESUMO

BACKGROUND There was a growing presumption that coinfection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and another viral respiratory illness was nonexistent. Although there has been an increasing number of coinfection cases since the beginning of the SARS-CoV-2 pandemic, there is still a significant lack of information regarding the symptomatology, treatment, prognosis, and reasoning behind coinfection. This raises concern of the possibility of misdiagnosis or delay in treatment. CASE REPORT This case report discusses a coinfection of SARS-CoV-2 and Influenza A in a 32-year-old man to highlight that these viruses can coexist within the same patient. This patient unfortunately died of persistent respiratory failure after several days in the ICU. CONCLUSIONS Coinfection of SARS-CoV-2 and Influenza A can occur and lead to a poor prognosis.


Assuntos
/diagnóstico , Coinfecção , Vírus da Influenza A/genética , Influenza Humana/diagnóstico , RNA Viral/análise , /genética , Adulto , Humanos , Influenza Humana/epidemiologia , Masculino , Radiografia Torácica , Tomografia Computadorizada por Raios X
9.
Nat Commun ; 11(1): 5511, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33139731

RESUMO

Parallel molecular evolution and adaptation are important phenomena commonly observed in viruses. Here, we exploit parallel molecular evolution to understand virulence evolution in avian influenza viruses (AIV). Highly-pathogenic AIVs evolve independently from low-pathogenic ancestors via acquisition of polybasic cleavage sites. Why some AIV lineages but not others evolve in this way is unknown. We hypothesise that the parallel emergence of highly-pathogenic AIV may be facilitated by permissive or compensatory mutations occurring across the viral genome. We combine phylogenetic, statistical and structural approaches to discover parallel mutations in AIV genomes associated with the highly-pathogenic phenotype. Parallel mutations were screened using a statistical test of mutation-phenotype association and further evaluated in the contexts of positive selection and protein structure. Our resulting mutational panel may help to reveal new links between virulence evolution and other traits, and raises the possibility of predicting aspects of AIV evolution.


Assuntos
Evolução Molecular , Vírus da Influenza A/patogenicidade , Influenza Aviária/virologia , Influenza Humana/virologia , Virulência/genética , Animais , Sequência de Bases/genética , Aves/virologia , Conjuntos de Dados como Assunto , Genoma Viral/genética , Humanos , Vírus da Influenza A/genética , Influenza Aviária/transmissão , Influenza Humana/transmissão , Mutação , Filogenia , Estabilidade Proteica , Seleção Genética , Alinhamento de Sequência , Proteínas Virais/genética
10.
BMC Infect Dis ; 20(1): 863, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213361

RESUMO

BACKGROUND: While hospital-acquired influenza A results in an additional cost burden and considerable mortality in patients, its risk factors are unknown. We aimed to describe the characteristics of patients vulnerable to hospital-acquired influenza A and to identify its risk factors to assist clinicians control hospital-acquired infections and reduce the burden of treatment. METHODS: A case-control study was conducted among hospitalized patients aged ≥18 years at a tertiary level teaching hospital during the 2018-2019 influenza A season. Patient data were retrieved from hospital-based electronic medical records. Hospital-acquired influenza A was defined as a case of influenza A diagnosed 7 days or more after admission, in a patient with no evidence of influenza A infection on admission. The controls without influenza A were selected among patients exposed to the same setting and time period. We identified risk factors using conditional logistic regression and described the characteristics of hospital-acquired influenza A by comparing the clinical data of infected patients and the controls. RESULTS: Of the 412 hospitalized patients with influenza A from all the departments in the study hospital, 93 (22.6%) cases were classified as hospital-acquired. The most common comorbidities of the 93 cases were hypertension (41.9%), coronary heart disease (21.5%), and cerebrovascular disease (20.4%). Before the onset of hospital-acquired influenza A, patients presented more lymphocytopenia (51.6% vs 35.5%, P = 0.027), hypoalbuminemia (78.5% vs 57.0%, P = 0.002), and pleural effusion (26.9% vs 9.7%, P = 0.002) than the matched controls. Infected patients also had longer hospital stays (18 days vs 14 days, P = 0.002), and higher mortality rates (10.8% vs 2.2%, P = 0.017) than the matched controls. Lymphocytopenia (odds ratio [OR]: 3.11; 95% confidence interval [CI]: 1.24-7.80; P = 0.016), hypoalbuminemia (OR: 2.24; 95% CI: 1.10-4.57; P = 0.027), and pleural effusion (OR: 3.09; 95% CI: 1.26-7.58; P = 0.014) were independently associated with hospital-acquired influenza A. CONCLUSIONS: Lymphocytopenia, hypoalbuminemia and pleural effusion are independent risk factors that can help identify patients at high risk of hospital-acquired influenza A, which can extend hospital stay and is associated with a high mortality.


Assuntos
Infecção Hospitalar/diagnóstico , Influenza Humana/diagnóstico , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Comorbidade , Infecção Hospitalar/epidemiologia , Feminino , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Razão de Chances , RNA Viral/metabolismo , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária , Adulto Jovem
11.
Front Cell Infect Microbiol ; 10: 563850, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194802

RESUMO

There is abundant evidence that the innate immune response to influenza A virus (IAV) is highly complex and plays a key role in protection against IAV induced infection and illness. Unfortunately it also clear that aspects of innate immunity can lead to severe morbidity or mortality from IAV, including inflammatory lung injury, bacterial superinfection, and exacerbation of reactive airways disease. We review broadly the virus and host factors that result in adverse outcomes from IAV and show evidence that inflammatory responses can become damaging even apart from changes in viral replication per se, with special focus on the positive and adverse effects of neutrophils and monocytes. We then evaluate in detail the role of soluble innate inhibitors including surfactant protein D and antimicrobial peptides that have a potential dual capacity for down-regulating viral replication and also inhibiting excessive inflammatory responses and how these innate host factors could possibly be harnessed to treat IAV infection. Where appropriate we draw comparisons and contrasts the SARS-CoV viruses and IAV in an effort to point out where the extensive knowledge existing regarding severe IAV infection could help guide research into severe COVID 19 illness or vice versa.


Assuntos
/imunologia , Imunidade Inata , Vírus da Influenza A/fisiologia , Influenza Humana/imunologia , /fisiologia , Animais , /virologia , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/patogenicidade , Influenza Humana/patologia , Influenza Humana/virologia , /patogenicidade , Replicação Viral
12.
J Clin Microbiol ; 59(1)2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33067271

RESUMO

Broad testing for respiratory viruses among persons under investigation (PUIs) for SARS-CoV-2 has been performed inconsistently, limiting our understanding of alternative viral infections and coinfections in these patients. RNA metagenomic next-generation sequencing (mNGS) offers an agnostic tool for the detection of both SARS-CoV-2 and other RNA respiratory viruses in PUIs. Here, we used RNA mNGS to assess the frequencies of alternative viral infections in SARS-CoV-2 RT-PCR-negative PUIs (n = 30) and viral coinfections in SARS-CoV-2 RT-PCR-positive PUIs (n = 45). mNGS identified all viruses detected by routine clinical testing (influenza A [n = 3], human metapneumovirus [n = 2], and human coronavirus OC43 [n = 2], and human coronavirus HKU1 [n = 1]). mNGS also identified both coinfections (1, 2.2%) and alternative viral infections (4, 13.3%) that were not detected by routine clinical workup (respiratory syncytial virus [n = 3], human metapneumovirus [n = 1], and human coronavirus NL63 [n = 1]). Among SARS-CoV-2 RT-PCR-positive PUIs, lower cycle threshold (CT ) values correlated with greater SARS-CoV-2 read recovery by mNGS (R 2, 0.65; P < 0.001). Our results suggest that current broad-spectrum molecular testing algorithms identify most respiratory viral infections among SARS-CoV-2 PUIs, when available and implemented consistently.


Assuntos
Betacoronavirus/isolamento & purificação , Coronavirus Humano OC43/isolamento & purificação , Vírus da Influenza A/isolamento & purificação , Metapneumovirus/isolamento & purificação , /isolamento & purificação , Betacoronavirus/genética , Coinfecção/virologia , Coronavirus Humano OC43/genética , Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Vírus da Influenza A/genética , Metagenoma , Metagenômica , Metapneumovirus/genética , /genética
13.
Am J Trop Med Hyg ; 103(4): 1642-1648, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32876004

RESUMO

False-negative rapid influenza diagnostic test (RIDT) results could mislead physicians to exclude an influenza diagnosis. We sought to evaluate the association between negative RIDT and intensive care unit (ICU) admission. We reviewed data from hospitalized adults with laboratory-confirmed influenza virus infections in a tertiary referral hospital in Taiwan from July 2009 to February 2011. The diagnosis was documented by real-time PCR or virus culture. Of 134 hospitalized adults infected with influenza virus, 38 (28%) were admitted to the ICU. Compared with RIDT-positive patients, the percentage of ICU admission was significantly higher among RIDT-negative patients (46% versus 13%, P < 0.001). The RIDT-negative patients had higher percentages of lower respiratory symptoms and more chest radiograph infiltrates. The time interval between the RIDT and antiviral treatment was longer in RIDT-negative than RIDT-positive patients (1.94 days versus 0.03 days, P < 0.001). Among patients presenting with mild illness, only a negative RIDT and delayed antiviral treatment were associated with ICU admission after adjusting for potential confounding factors. To conclude, patients with a negative RIDT were more likely to have severe disease and a delay in initiating antiviral treatment. Our findings should help improve treatment outcomes of hospitalized patients with influenza infection.


Assuntos
Antivirais/uso terapêutico , Vírus da Influenza A/isolamento & purificação , Influenza Humana/diagnóstico , Adulto , Idoso , Reações Falso-Negativas , Feminino , Hospitalização , Humanos , Vírus da Influenza A/genética , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Unidades de Terapia Intensiva , Laboratórios , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Taiwan
14.
Eur Rev Med Pharmacol Sci ; 24(17): 9196-9201, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32965014

RESUMO

OBJECTIVE: The aim of this study is to find the distributions of pathogens in 164 suspected COVID-19 patients from the outpatient clinic of Shenjing Hospital of China Medical University from 24th January, 2020, to 29th February of 2020. PATIENTS AND METHODS: 164 COVID-19 suspected patients were from the Shengjing Hospital of China Medical University. Oropharyngeal swab specimens were acquired by respiratory doctors under standardized conditions. Specific nucleic acids of SARS-CoV-2, influenza A and B, respiratory syncytial virus A and B, adenovirus, parainfluenza virus, along with pneumonic mycoplasma were detected by real-time fluorescence PCR. Symptomatic, epidemiologic, laboratory and radiological data of the patients were obtained from the electronic medical record system of our hospital. RESULTS: Among the 164 patients, 3 were positive for SARS-CoV-2, 15 were positive for other respiratory viruses and 16 were positive for pneumonic mycoplasma. Of the positive patients above, 1 patient was co-infected with SARS-CoV-2 and adenovirus, and 1 was co-infected with influenza B and pneumonic mycoplasma. The 3 SARS-CoV-2 infected patients were clinically diagnosed as COVID-19 because they meet the diagnostic criteria listed in "Chinese Clinical Guidance for COVID-19 Pneumonia diagnosis and treatment", including epidemic history, symptom and pathogenic detection, as well as abnormalities of the laboratory and radiological data. However, the clinical characteristics of COVID-19 patients were non-specific compared to those of the patients infected with other respiratory viruses. CONCLUSIONS: The endemic common respiratory pathogens are more prevalent than SARS-CoV-2 in the SARS-CoV-2 non-epidemic areas of this research. Detection of the pathogen is the unique means for definite COVID-19 diagnosis.


Assuntos
Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Adenoviridae/genética , Adenoviridae/isolamento & purificação , Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Influenzavirus B/genética , Influenzavirus B/isolamento & purificação , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Tórax/diagnóstico por imagem , Tomografia Computadorizada por Raios X
15.
J Virol ; 94(23)2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907981

RESUMO

The genesis of novel influenza viruses through reassortment poses a continuing risk to public health. This is of particular concern in Bangladesh, where highly pathogenic avian influenza viruses of the A(H5N1) subtype are endemic and cocirculate with other influenza viruses. Active surveillance of avian influenza viruses in Bangladeshi live poultry markets detected three A(H5) genotypes, designated H5N1-R1, H5N1-R2, and H5N2-R3, that arose from reassortment of A(H5N1) clade 2.3.2.1a viruses. The H5N1-R1 and H5N1-R2 viruses contained HA, NA, and M genes from the A(H5N1) clade 2.3.2.1a viruses and PB2, PB1, PA, NP, and NS genes from other Eurasian influenza viruses. H5N2-R3 viruses contained the HA gene from circulating A(H5N1) clade 2.3.2.1a viruses, NA and M genes from concurrently circulating A(H9N2) influenza viruses, and PB2, PB1, PA, NP, and NS genes from other Eurasian influenza viruses. Representative viruses of all three genotypes and a parental clade 2.3.2.1a strain (H5N1-R0) infected and replicated in mice without prior adaptation; the H5N2-R3 virus replicated to the highest titers in the lung. All viruses efficiently infected and killed chickens. All viruses replicated in inoculated ferrets, but no airborne transmission was detected, and only H5N2-R3 showed limited direct-contact transmission. Our findings demonstrate that although the A(H5N1) viruses circulating in Bangladesh have the capacity to infect and replicate in mammals, they show very limited capacity for transmission. However, reassortment does generate viruses of distinct phenotypes.IMPORTANCE Highly pathogenic avian influenza A(H5N1) viruses have circulated continuously in Bangladesh since 2007, and active surveillance has detected viral evolution driven by mutation and reassortment. Recently, three genetically distinct A(H5N1) reassortant viruses were detected in live poultry markets in Bangladesh. Currently, we cannot assign pandemic risk by only sequencing viruses; it must be conducted empirically. We found that the H5Nx highly pathogenic avian influenza viruses exhibited high virulence in mice and chickens, and one virus had limited capacity to transmit between ferrets, a property considered consistent with a higher zoonotic risk.


Assuntos
Vírus da Influenza A/classificação , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Mamíferos/virologia , Filogenia , Aves Domésticas/virologia , Animais , Bangladesh/epidemiologia , Galinhas , Furões , Genoma Viral , Genótipo , Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A Subtipo H5N2 , Vírus da Influenza A Subtipo H9N2 , Vírus da Influenza A/genética , Influenza Aviária/patologia , Influenza Aviária/transmissão , Pulmão/patologia , Camundongos , Pandemias , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Vírus Reordenados/genética , Proteínas não Estruturais Virais/genética , Virulência
16.
Proc Natl Acad Sci U S A ; 117(40): 24964-24973, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32958663

RESUMO

Influenza A virus (IAV) infection during pregnancy causes severe maternal and perinatal complications, despite a lack of vertical transmission of IAV across the placenta. Here, we demonstrate a significant alteration in the maternal vascular landscape that underpins the maternal and downstream fetal pathology to IAV infection in mice. In IAV infection of nonpregnant mice, the local lung inflammatory response was contained to the lungs and was self-resolving, whereas in pregnant mice, virus dissemination to major maternal blood vessels, including the aorta, resulted in a peripheral "vascular storm," with elevated proinflammatory and antiviral mediators and the influx of Ly6Clow and Ly6Chigh monocytes, plus neutrophils and T cells. This vascular storm was associated with elevated levels of the adhesion molecules ICAM and VCAM and the pattern-recognition receptors TLR7 and TLR9 in the vascular wall, resulting in profound vascular dysfunction. The sequalae of this IAV-driven vascular storm included placental growth retardation and intrauterine growth restriction, evidence of placental and fetal brain hypoxia, and increased circulating cell free fetal DNA and soluble Flt1. In contrast, IAV infection in nonpregnant mice caused no obvious alterations in endothelial function or vascular inflammation. Therefore, IAV infection during pregnancy drives a significant systemic vascular alteration in pregnant dams, which likely suppresses critical blood flow to the placenta and fetus. This study in mice provides a fundamental mechanistic insight and a paradigm into how an immune response to a respiratory virus, such as IAV, is likely to specifically drive maternal and fetal pathologies during pregnancy.


Assuntos
Imunidade Adaptativa/genética , Imunidade Inata/genética , Inflamação/genética , Vírus da Influenza A/genética , Animais , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Feminino , Feto/imunologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Inflamação/virologia , Vírus da Influenza A/patogenicidade , Influenza Humana/genética , Influenza Humana/imunologia , Influenza Humana/virologia , Glicoproteínas de Membrana/genética , Camundongos , Monócitos/metabolismo , Monócitos/patologia , Placenta/irrigação sanguínea , Placenta/imunologia , Placenta/virologia , Gravidez , Linfócitos T/imunologia , Linfócitos T/virologia , Receptor 7 Toll-Like/genética , Receptor Toll-Like 9/genética
17.
Nucleic Acids Res ; 48(18): 10428-10440, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32960265

RESUMO

Cellular exonucleases involved in the processes that regulate RNA stability and quality control have been shown to restrict or to promote the multiplication cycle of numerous RNA viruses. Influenza A viruses are major human pathogens that are responsible for seasonal epidemics, but the interplay between viral proteins and cellular exonucleases has never been specifically studied. Here, using a stringent interactomics screening strategy and an siRNA-silencing approach, we identified eight cellular factors among a set of 75 cellular proteins carrying exo(ribo)nuclease activities or involved in RNA decay processes that support influenza A virus multiplication. We show that the exoribonuclease ERI1 interacts with the PB2, PB1 and NP components of the viral ribonucleoproteins and is required for viral mRNA transcription. More specifically, we demonstrate that the protein-protein interaction is RNA dependent and that both the RNA binding and exonuclease activities of ERI1 are required to promote influenza A virus transcription. Finally, we provide evidence that during infection, the SLBP protein and histone mRNAs co-purify with vRNPs alongside ERI1, indicating that ERI1 is most probably recruited when it is present in the histone pre-mRNA processing complex in the nucleus.


Assuntos
Exorribonucleases/genética , Vírus da Influenza A/genética , Influenza Humana/genética , Proteínas Nucleares/genética , Fatores de Poliadenilação e Clivagem de mRNA/genética , Linhagem Celular , Histonas/genética , Interações Hospedeiro-Patógeno , Humanos , Vírus da Influenza A/patogenicidade , Influenza Humana/virologia , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Interferente Pequeno , RNA Viral/genética , Ribonucleoproteínas/genética , Transcrição Genética/genética , Proteínas Virais/genética , Replicação Viral/genética
18.
PLoS Pathog ; 16(8): e1008775, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866218

RESUMO

Small RNA viruses only have a very limited coding capacity, thus most viral proteins have evolved to fulfill multiple functions. The highly conserved matrix protein 1 (M1) of influenza A viruses is a prime example for such a multifunctional protein, as it acts as a master regulator of virus replication whose different functions have to be tightly regulated. The underlying mechanisms, however, are still incompletely understood. Increasing evidence points towards an involvement of posttranslational modifications in the spatio-temporal regulation of M1 functions. Here, we analyzed the role of M1 tyrosine phosphorylation in genuine infection by using recombinant viruses expressing M1 phosphomutants. Presence of M1 Y132A led to significantly decreased viral replication compared to wildtype and M1 Y10F. Characterization of phosphorylation dynamics by mass spectrometry revealed the presence of Y132 phosphorylation in M1 incorporated into virions that is most likely mediated by membrane-associated Janus kinases late upon infection. Molecular dynamics simulations unraveled a potential phosphorylation-induced exposure of the positively charged linker domain between helices 4 and 5, supposably acting as interaction platform during viral assembly. Consistently, M1 Y132A showed a defect in lipid raft localization due to reduced interaction with viral HA protein resulting in a diminished structural stability of viral progeny and the formation of filamentous particles. Importantly, reduced M1-RNA binding affinity resulted in an inefficient viral genome incorporation and the production of non-infectious virions that interferes with virus pathogenicity in mice. This study advances our understanding of the importance of dynamic phosphorylation as a so far underestimated level of regulation of multifunctional viral proteins and emphasizes the potential feasibility of targeting posttranslational modifications of M1 as a novel antiviral intervention.


Assuntos
Vírus da Influenza A/metabolismo , Mutação de Sentido Incorreto , Proteínas da Matriz Viral/metabolismo , Células A549 , Substituição de Aminoácidos , Animais , Cães , Feminino , Células HEK293 , Humanos , Vírus da Influenza A/genética , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Transgênicos , Fosforilação , Proteínas da Matriz Viral/genética
19.
BMC Infect Dis ; 20(1): 648, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883215

RESUMO

BACKGROUND: Due to the frequent reassortment and zoonotic potential of influenza A viruses, rapid gain of sequence information is crucial. Alongside established next-generation sequencing protocols, the MinION sequencing device (Oxford Nanopore Technologies) has become a serious competitor for routine whole-genome sequencing. Here, we established a novel, rapid and high-throughput MinION multiplexing workflow based on a universal RT-PCR. METHODS: Twelve representative influenza A virus samples of multiple subtypes were universally amplified in a one-step RT-PCR and subsequently sequenced on the MinION instrument in conjunction with a barcoding library preparation kit from the rapid family and the MinIT performing live base-calling. The identical PCR products were sequenced on an IonTorrent platform and, after final consensus assembly, all data was compared for validation. To prove the practicability of the MinION-MinIT method in human and veterinary diagnostics, we sequenced recent and historical influenza strains for further benchmarking. RESULTS: The MinION-MinIT combination generated over two million reads for twelve samples in a six-hour sequencing run, from which a total of 72% classified as quality screened, trimmed and mapped influenza reads to produce full genome sequences. Identities between the datasets of > 99.9% were achieved, with 100% coverage of all segments alongside a sufficient confidence and 4492fold mean depth. From RNA extraction to finished sequences, only 14 h were required. CONCLUSIONS: Overall, we developed and validated a novel and rapid multiplex workflow for influenza A virus sequencing. This protocol suits both clinical and academic settings, aiding in real time diagnostics and passive surveillance.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Vírus da Influenza A/genética , Sequenciamento por Nanoporos/métodos , Humanos , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Fluxo de Trabalho
20.
J Virol ; 94(22)2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32847862

RESUMO

Influenza remains a global health risk and challenge. Currently, neuraminidase (NA) inhibitors are extensively used to treat influenza, but their efficacy is compromised by the emergence of drug-resistant variants. Neutralizing antibodies targeting influenza A virus surface glycoproteins are critical components of influenza therapeutic agents and may provide alternative strategies to the existing countermeasures. However, the major hurdle for the extensive application of antibody therapies lies in the difficulty of generating nonimmunogenic antibodies in large quantities rapidly. Here, we report that one human monoclonal antibody (MAb), 53C10, isolated from transchromosomic (Tc) cattle exhibits potent neutralization and hemagglutination inhibition titers against different clades of H1N1 subtype influenza A viruses. In vitro selection of antibody escape mutants revealed that 53C10 recognizes a novel noncontinuous epitope in the hemagglutinin (HA) head domain involving three amino acid residues, glycine (G), serine (S), and glutamic acid (E) at positions 172, 207, and 212, respectively. The results of our experiments supported a critical role for substitution of arginine at position 207 (S207R) in mediating resistance to 53C10, while substitutions at either G172E or E212A did not alter antibody recognition and neutralization. The E212A mutation may provide structural stability for the epitope, while the substitution G172E probably compensates for loss of fitness introduced by S207R. Our results offer novel insights into the mechanism of action of MAb 53C10 and indicate its potential role in therapeutic treatment of H1 influenza virus infection in humans.IMPORTANCE Respiratory diseases caused by influenza viruses still pose a serious concern to global health, and neutralizing antibodies constitute a promising area of antiviral therapeutics. However, the potential application of antibodies is often hampered by the challenge in generating nonimmunogenic antibodies in large scale. In the present study, transchromosomic (Tc) cattle were used for the generation of nonimmunogenic monoclonal antibodies (MAbs), and characterization of such MAbs revealed one monoclonal antibody, 53C10, exhibiting a potent neutralization activity against H1N1 influenza viruses. Further characterization of the neutralization escape mutant generated using this MAb showed that three amino acid substitutions in the HA head domain contributed to the resistance. These findings emphasize the importance of Tc cattle in the production of nonimmunogenic MAbs and highlight the potential of MAb 53C10 in the therapeutic application against H1 influenza virus infection in humans.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Bovinos , Linhagem Celular , Humanos , Evasão da Resposta Imune , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A/genética , Modelos Moleculares , Mutação , Testes de Neutralização , Análise de Sequência de Proteína
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