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1.
PLoS One ; 17(1): e0262162, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34982806

RESUMO

Analysis of convalescent plasma derived from individuals has shown that IgG3 has the most important role in binding to SARS-CoV-2 antigens; however, this has not yet been confirmed in large studies, and the link between binding and neutralization has not been confirmed. By analyzing plasma pools consisting of 247-567 individual convalescent donors, we demonstrated the binding of IgG3 and IgM to Spike-1 protein and the receptor-binding domain correlates strongly with viral neutralization in vitro. Furthermore, despite accounting for only approximately 12% of total immunoglobulin mass, collectively IgG3 and IgM account for approximately 80% of the total neutralization. This may have important implications for the development of potent therapies for COVID-19, as it indicates that hyperimmune globulins or convalescent plasma donations with high IgG3 concentrations may be a highly efficacious therapy.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/imunologia , Convalescença , Imunoglobulina G/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Chlorocebus aethiops , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , SARS-CoV-2/fisiologia , Células Vero
2.
PLoS One ; 17(1): e0257963, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34986162

RESUMO

In times of crisis, including the current COVID-19 pandemic, the supply chain of filtering facepiece respirators, such as N95 respirators, are disrupted. To combat shortages of N95 respirators, many institutions were forced to decontaminate and reuse respirators. While several reports have evaluated the impact on filtration as a measurement of preservation of respirator function after decontamination, the equally important fact of maintaining proper fit to the users' face has been understudied. In the current study, we demonstrate the complete inactivation of SARS-CoV-2 and preservation of fit test performance of N95 respirators following treatment with dry heat. We apply scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) measurements, Raman spectroscopy, and contact angle measurements to analyze filter material changes as a consequence of different decontamination treatments. We further compared the integrity of the respirator after autoclaving versus dry heat treatment via quantitative fit testing and found that autoclaving, but not dry heat, causes the fit of the respirator onto the users face to fail, thereby rendering the decontaminated respirator unusable. Our findings highlight the importance to account for both efficacy of disinfection and mask fit when reprocessing respirators to for clinical redeployment.


Assuntos
COVID-19/prevenção & controle , Descontaminação/métodos , Reutilização de Equipamento , Respiradores N95/virologia , SARS-CoV-2/fisiologia , COVID-19/transmissão , Equipamentos e Provisões , Pessoal de Saúde , Temperatura Alta , Humanos , Pandemias
3.
MAbs ; 14(1): 2005507, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34923915

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a serious public health crisis worldwide, and considering the novelty of the disease, preventative and therapeutic measures alike are urgently needed. To accelerate such efforts, the development of JS016, a neutralizing monoclonal antibody directed against the SARS-CoV-2 spike protein, was expedited from a typical 12- to 18-month period to a 4-month period. During this process, transient Chinese hamster ovary cell lines are used to support preclinical, investigational new drug-enabling toxicology research, and early Chemistry, Manufacturing and Controls development; mini-pool materials to supply Phase 1 clinical trials; and a single-clone working cell bank for late-stage and pivotal clinical trials were successively adopted. Moreover, key process performance and product quality investigations using a series of orthogonal and state-of-the-art techniques were conducted to demonstrate the comparability of products manufactured using these three processes, and the results indicated that, despite observed variations in process performance, the primary and high-order structures, purity and impurity profiles, biological and immunological functions, and degradation behaviors under stress conditions were largely comparable. The study suggests that, in particular situations, this strategy can be adopted to accelerate the development of therapeutic biopharmaceuticals and their access to patients.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/uso terapêutico , Afinidade de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Células CHO , COVID-19/prevenção & controle , COVID-19/virologia , Cromatografia Líquida de Alta Pressão/métodos , Dicroísmo Circular , Células Clonais , Cricetinae , Cricetulus , Humanos , Imunoglobulina G/química , Imunoglobulina G/imunologia , Imunoglobulina G/uso terapêutico , Ponto Isoelétrico , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo
4.
Gut Microbes ; 14(1): 2018900, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34965194

RESUMO

Mounting evidence suggests that the gut-to-lung axis is critical during respiratory viral infections. We herein hypothesized that disruption of gut homeostasis during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may associate with early disease outcomes. To address this question, we took advantage of the Syrian hamster model. Our data confirmed that this model recapitulates some hallmark features of the human disease in the lungs. We further showed that SARS-CoV-2 infection associated with mild intestinal inflammation, relative alteration in intestinal barrier property and liver inflammation and altered lipid metabolism. These changes occurred concomitantly with an alteration of the gut microbiota composition over the course of infection, notably characterized by a higher relative abundance of deleterious bacterial taxa such as Enterobacteriaceae and Desulfovibrionaceae. Conversely, several members of the Ruminococcaceae and Lachnospiraceae families, including bacteria known to produce the fermentative products short-chain fatty acids (SCFAs), had a reduced relative proportion compared to non-infected controls. Accordingly, infection led to a transient decrease in systemic SCFA amounts. SCFA supplementation during infection had no effect on clinical and inflammatory parameters. Lastly, a strong correlation between some gut microbiota taxa and clinical and inflammation indices of SARS-CoV-2 infection severity was evidenced. Collectively, alteration of the gut microbiota correlates with disease severity in hamsters making this experimental model valuable for the design of interventional, gut microbiota-targeted, approaches for the control of COVID-19.Abbreviations: SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; COVID-19, coronavirus disease 2019; SCFAs, short-chain fatty acids; dpi, day post-infection; RT-PCR, reverse transcription polymerase chain reaction; IL, interleukin. ACE2, angiotensin converting enzyme 2; TMPRSS2, transmembrane serine protease 2.


Assuntos
COVID-19/microbiologia , COVID-19/fisiopatologia , Modelos Animais de Doenças , Microbioma Gastrointestinal , Mesocricetus , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/metabolismo , COVID-19/tratamento farmacológico , COVID-19/patologia , Cricetinae , Ácidos Graxos Voláteis/administração & dosagem , Ácidos Graxos Voláteis/metabolismo , Humanos , Masculino , SARS-CoV-2/fisiologia , Índice de Gravidade de Doença
5.
Endocrinology ; 163(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34543404

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic continues to exert a significant impact on global health care systems, causing devastating mortality and morbidity. As time passes and our understanding of this novel respiratory virus deepens, it is increasingly clear that its effects extend beyond that of the respiratory system. The coronavirus responsible for COVID-19, severe acute respiratory syndrome coronavirus 2, obtains cellular access through the angiotensin-converting enzyme 2 (ACE2) receptor in a process requiring the transmembrane serine protease 2 (TMPRSS2) protein. Both ACE2 and TMPRSS2 are widely expressed in many endocrine glands. This, along with several case reports of thyroid and pituitary disruption in patients with COVID-19, has resulted in significant interest in its impact on the endocrine system. Indeed, as mortality is abated by the increasing availability of effective vaccines, there is increasing focus on the long-term effects on health in COVID-19 survivors. This review summarizes data investigating the effects of COVID-19 on each of the endocrine axes to guide appropriate investigations and optimal management.


Assuntos
COVID-19/metabolismo , Sistema Endócrino/metabolismo , SARS-CoV-2/fisiologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/virologia , Humanos , Pandemias , SARS-CoV-2/genética , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo
6.
Int J Mol Med ; 49(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34935057

RESUMO

The pathophysiology of coronavirus disease 2019 (COVID­19) is mainly dependent on the underlying mechanisms that mediate the entry of severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) into the host cells of the various human tissues/organs. Recent studies have indicated a higher order of complexity of the mechanisms of infectivity, given that there is a wide­repertoire of possible cell entry mediators that appear to co­localise in a cell­ and tissue­specific manner. The present study provides an overview of the 'canonical' SARS­CoV­2 mediators, namely angiotensin converting enzyme 2, transmembrane protease serine 2 and 4, and neuropilin­1, expanding on the involvement of novel candidates, including glucose­regulated protein 78, basigin, kidney injury molecule­1, metabotropic glutamate receptor subtype 2, ADAM metallopeptidase domain 17 (also termed tumour necrosis factor­α convertase) and Toll­like receptor 4. Furthermore, emerging data indicate that changes in microRNA (miRNA/miR) expression levels in patients with COVID­19 are suggestive of further complexity in the regulation of these viral mediators. An in silico analysis revealed 160 candidate miRNAs with potential strong binding capacity in the aforementioned genes. Future studies should concentrate on elucidating the association between the cellular tropism of the SARS­CoV­2 cell entry mediators and the mechanisms through which they might affect the clinical outcome. Finally, the clinical utility as a biomarker or therapeutic target of miRNAs in the context of COVID­19 warrants further investigation.


Assuntos
COVID-19/metabolismo , MicroRNAs/metabolismo , Receptores Virais/metabolismo , SARS-CoV-2/metabolismo , Internalização do Vírus , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/genética , COVID-19/virologia , /metabolismo , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , MicroRNAs/genética , Neuropilina-1/genética , Neuropilina-1/metabolismo , Receptores Virais/genética , SARS-CoV-2/fisiologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Tropismo Viral
7.
J Med Virol ; 94(1): 240-245, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34460115

RESUMO

Many countries in the world are experiencing a recent surge in COVID-19 cases. This is mainly attributed to the emergence of new SARS-CoV-2 variants. Genome sequencing is the only means to detect the evolving virus mutants and emerging variants. Cycle threshold values have an inverse relationship with viral load and lower Ct values are also found to be associated with increased infectivity. In this study, we propose to use Ct values as an early indicator for upcoming COVID-19 waves. A retrospective cross-sectional study was carried out to analyze the Ct values of positive samples reported during the first wave and second wave (April 2020-May 2021). Median Ct values of confirmatory genes were taken into consideration for comparison. Ct values below 25, >25-30, and >30 were categorized as high, moderate, and low viral load respectively. Our study found a significantly higher proportion of positive samples with a low Ct value (<25) across age groups and gender during the second wave of the COVID-19 pandemic. A higher proportion of positive samples with a low Ct value (high viral load) may act as an early indicator of an upcoming surge.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , COVID-19/epidemiologia , Adolescente , Adulto , Infecções Assintomáticas/epidemiologia , COVID-19/virologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2/fisiologia , Carga Viral , Adulto Jovem
8.
Life Sci Alliance ; 5(1)2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34764206

RESUMO

Understanding pathways that might impact coronavirus disease 2019 (COVID-19) manifestations and disease outcomes is necessary for better disease management and for therapeutic development. Here, we analyzed alterations in sphingolipid (SL) levels upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 infection induced elevation of SL levels in both cells and sera of infected mice. A significant increase in glycosphingolipid levels was induced early post SARS-CoV-2 infection, which was essential for viral replication. This elevation could be reversed by treatment with glucosylceramide synthase inhibitors. Levels of sphinganine, sphingosine, GA1, and GM3 were significantly increased in both cells and the murine model upon SARS-CoV-2 infection. The potential involvement of SLs in COVID-19 pathology is discussed.


Assuntos
COVID-19/metabolismo , Modelos Animais de Doenças , Esfingolipídeos/metabolismo , Replicação Viral/fisiologia , Animais , COVID-19/prevenção & controle , COVID-19/virologia , Chlorocebus aethiops , Cromatografia Líquida/métodos , Dioxanos/farmacologia , Gangliosídeos/sangue , Gangliosídeos/metabolismo , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/metabolismo , Humanos , Espectrometria de Massas/métodos , Camundongos Transgênicos , Pirrolidinas/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Esfingolipídeos/sangue , Esfingosina/análogos & derivados , Esfingosina/sangue , Esfingosina/metabolismo , Células Vero , Replicação Viral/efeitos dos fármacos
9.
Oncol Rep ; 47(1)2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34779496

RESUMO

The devastating complications of coronavirus disease 2019 (COVID­19) result from the dysfunctional immune response of an individual following the initial severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) infection. Multiple toxic stressors and behaviors contribute to underlying immune system dysfunction. SARS­CoV­2 exploits the dysfunctional immune system to trigger a chain of events, ultimately leading to COVID­19. The authors have previously identified a number of contributing factors (CFs) common to myriad chronic diseases. Based on these observations, it was hypothesized that there may be a significant overlap between CFs associated with COVID­19 and gastrointestinal cancer (GIC). Thus, in the present study, a streamlined dot­product approach was used initially to identify potential CFs that affect COVID­19 and GIC directly (i.e., the simultaneous occurrence of CFs and disease in the same article). The nascent character of the COVID­19 core literature (~1­year­old) did not allow sufficient time for the direct effects of numerous CFs on COVID­19 to emerge from laboratory experiments and epidemiological studies. Therefore, a literature­related discovery approach was used to augment the COVID­19 core literature­based 'direct impact' CFs with discovery­based 'indirect impact' CFs [CFs were identified in the non­COVID­19 biomedical literature that had the same biomarker impact pattern (e.g., hyperinflammation, hypercoagulation, hypoxia, etc.) as was shown in the COVID­19 literature]. Approximately 2,250 candidate direct impact CFs in common between GIC and COVID­19 were identified, albeit some being variants of the same concept. As commonality proof of concept, 75 potential CFs that appeared promising were selected, and 63 overlapping COVID­19/GIC potential/candidate CFs were validated with biological plausibility. In total, 42 of the 63 were overlapping direct impact COVID­19/GIC CFs, and the remaining 21 were candidate GIC CFs that overlapped with indirect impact COVID­19 CFs. On the whole, the present study demonstrates that COVID­19 and GIC share a number of common risk/CFs, including behaviors and toxic exposures, that impair immune function. A key component of immune system health is the removal of those factors that contribute to immune system dysfunction in the first place. This requires a paradigm shift from traditional Western medicine, which often focuses on treatment, rather than prevention.


Assuntos
COVID-19/epidemiologia , Neoplasias Gastrointestinais/epidemiologia , COVID-19/etiologia , COVID-19/imunologia , Neoplasias Gastrointestinais/etiologia , Neoplasias Gastrointestinais/imunologia , Humanos , Fatores de Risco , SARS-CoV-2/fisiologia , Fatores Socioeconômicos
10.
J Med Virol ; 94(1): 161-172, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34415583

RESUMO

Detailed information on intrahost viral evolution in SARS-CoV-2 with and without treatment is limited. Sequential viral loads and deep sequencing of SARS-CoV-2 from the upper respiratory tract of nine hospitalized children, three of whom were treated with remdesivir, revealed that remdesivir treatment suppressed viral load in one patient but not in a second infected with an identical strain without any evidence of drug resistance found. Reduced levels of subgenomic RNA during treatment of the second patient, suggest an additional effect of remdesivir on viral replication. Haplotype reconstruction uncovered persistent SARS-CoV-2 variant genotypes in four patients. These likely arose from within-host evolution, although superinfection cannot be excluded in one case. Although our dataset is small, observed sample-to-sample heterogeneity in variant frequencies across four of nine patients suggests the presence of discrete viral populations in the lung with incomplete population sampling in diagnostic swabs. Such compartmentalization could compromise the penetration of remdesivir into the lung, limiting the drugs in vivo efficacy, as has been observed in other lung infections.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/virologia , Evolução Molecular , SARS-CoV-2/genética , Monofosfato de Adenosina/uso terapêutico , Adolescente , Alanina/uso terapêutico , Criança , Pré-Escolar , Farmacorresistência Viral , Feminino , Haplótipos , Humanos , Lactente , Pulmão/virologia , Masculino , Filogenia , RNA Viral/análise , RNA Viral/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Carga Viral , Replicação Viral/efeitos dos fármacos
11.
Virology ; 565: 73-81, 2022 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-34742127

RESUMO

Bacillus Calmette-Guérin (BCG) vaccine is currently used to prevent tuberculosis infection. The vaccine was found to enhance resistance to certain types of infection including positive sense RNA viruses. The current COVID-19 pandemic is caused by positive sense RNA, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A higher mortality rate of COVID-19 patients was reported in countries where BCG vaccination is not routinely administered, when compared to the vaccinated ones. We hypothesized that BCG vaccine may control SARS-CoV2 infection via modulating the monocyte immune response. We analyzed GSE104149 dataset to investigate whether human monocytes of BCG-vaccinated individuals acquire resistance to SARS-CoV-2 infection. Differentially expressed genes obtained from the dataset were used to determine enriched pathways, biological processes, and molecular functions for monocytes post BCG vaccination. Our data show that BCG vaccine promotes a more effective immune response of monocytes against SARS-CoV2, but probably not sufficient to prevent the infection.


Assuntos
Vacina BCG/imunologia , COVID-19/epidemiologia , Vacinação/estatística & dados numéricos , Vacina BCG/administração & dosagem , COVID-19/prevenção & controle , Perfilação da Expressão Gênica , Humanos , Inflamação , Monócitos/imunologia , Monócitos/virologia , SARS-CoV-2/fisiologia
12.
Eur J Med Chem ; 227: 113966, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34749200

RESUMO

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unprecedented in human history. As a major structural protein, nucleocapsid protein (NPro) is critical to the replication of SARS-CoV-2. In this work, 17 NPro-targeting phenanthridine derivatives were rationally designed and synthesized, based on the crystal structure of NPro. Most of these compounds can interact with SARS-CoV-2 NPro tightly and inhibit the replication of SARS-CoV-2 in vitro. Compounds 12 and 16 exhibited the most potent anti-viral activities with 50% effective concentration values of 3.69 and 2.18 µM, respectively. Furthermore, site-directed mutagenesis of NPro and Surface Plasmon Resonance (SPR) assays revealed that 12 and 16 target N-terminal domain (NTD) of NPro by binding to Tyr109. This work found two potent anti-SARS-CoV-2 bioactive compounds and also indicated that SARS-CoV-2 NPro-NTD can be a target for new anti-virus agents.


Assuntos
Antivirais/química , Proteínas do Nucleocapsídeo de Coronavírus/antagonistas & inibidores , Fenantridinas/química , SARS-CoV-2/metabolismo , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Antivirais/uso terapêutico , Sítios de Ligação , COVID-19/tratamento farmacológico , COVID-19/virologia , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Desenho de Fármacos , Humanos , Cinética , Simulação de Acoplamento Molecular , Fenantridinas/metabolismo , Fenantridinas/farmacologia , Fenantridinas/uso terapêutico , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Células Vero
13.
Cell Rep ; 37(12): 110126, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34910942

RESUMO

Previous studies have shown that the high mortality caused by viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza virus primarily results from complications of a cytokine storm. Therefore, it is critical to identify the key factors participating in the cytokine storm. Here we demonstrate that interferon-induced protein 35 (IFP35) plays an important role in the cytokine storm induced by SARS-CoV-2 and influenza virus infection. We find that the levels of serum IFP35 in individuals with SARS-CoV-2 correlates with severity of the syndrome. Using mouse model and cell assays, we show that IFP35 is released by lung epithelial cells and macrophages after SARS-CoV-2 or influenza virus infection. In addition, we show that administration of neutralizing antibodies against IFP35 considerably reduces lung injury and, thus, the mortality rate of mice exposed to viral infection. Our findings suggest that IFP35 serves as a biomarker and as a therapeutic target in virus-induced syndromes.


Assuntos
COVID-19/sangue , COVID-19/tratamento farmacológico , Influenza Humana/sangue , Influenza Humana/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/sangue , Animais , Anticorpos Neutralizantes/administração & dosagem , Biomarcadores/sangue , COVID-19/patologia , COVID-19/fisiopatologia , Modelos Animais de Doenças , Humanos , Inflamação/metabolismo , Influenza Humana/patologia , Pulmão/metabolismo , Pulmão/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravidade do Paciente , SARS-CoV-2/fisiologia
14.
Sci Rep ; 11(1): 24124, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34916534

RESUMO

The quantification of spreading heterogeneity in the COVID-19 epidemic is crucial as it affects the choice of efficient mitigating strategies irrespective of whether its origin is biological or social. We present a method to deduce temporal and individual variations in the basic reproduction number directly from epidemic trajectories at a community level. Using epidemic data from the 98 districts in Denmark we estimate an overdispersion factor k for COVID-19 to be about 0.11 (95% confidence interval 0.08-0.18), implying that 10 % of the infected cause between 70 % and 87 % of all infections.


Assuntos
Algoritmos , Número Básico de Reprodução/estatística & dados numéricos , COVID-19/transmissão , Modelos Teóricos , SARS-CoV-2/isolamento & purificação , COVID-19/epidemiologia , COVID-19/virologia , Dinamarca/epidemiologia , Epidemias/prevenção & controle , Geografia , Humanos , SARS-CoV-2/fisiologia
15.
Sci Rep ; 11(1): 23378, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34916540

RESUMO

Emissions of black carbon (BC) particles from anthropogenic and natural sources contribute to climate change and human health impacts. Therefore, they need to be accurately quantified to develop an effective mitigation strategy. Although the spread of the emission flux estimates for China have recently narrowed under the constraints of atmospheric observations, consensus has not been reached regarding the dominant emission sector. Here, we quantified the contribution of the residential sector, as 64% (44-82%) in 2019, using the response of the observed atmospheric concentration in the outflowing air during Feb-Mar 2020, with the prevalence of the COVID-19 pandemic and restricted human activities over China. In detail, the BC emission fluxes, estimated after removing effects from meteorological variability, dropped only slightly (- 18%) during Feb-Mar 2020 from the levels in the previous year for selected air masses of Chinese origin, suggesting the contributions from the transport and industry sectors (36%) were smaller than the rest from the residential sector (64%). Carbon monoxide (CO) behaved differently, with larger emission reductions (- 35%) in the period Feb-Mar 2020, suggesting dominance of non-residential (i.e., transport and industry) sectors, which contributed 70% (48-100%) emission during 2019. The estimated BC/CO emission ratio for these sectors will help to further constrain bottom-up emission inventories. We comprehensively provide a clear scientific evidence supporting mitigation policies targeting reduction in residential BC emissions from China by demonstrating the economic feasibility using marginal abatement cost curves.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , COVID-19/prevenção & controle , Material Particulado/análise , SARS-CoV-2/isolamento & purificação , Fuligem/análise , Algoritmos , Atmosfera/análise , COVID-19/epidemiologia , COVID-19/virologia , China , Mudança Climática , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Geografia , Atividades Humanas , Humanos , Modelos Teóricos , Pandemias , Características de Residência , SARS-CoV-2/fisiologia , Estações do Ano , Vento
16.
Sci Rep ; 11(1): 24108, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34916547

RESUMO

Despite the great potential of Virtual Reality (VR) to arouse emotions, there are no VR affective databases available as it happens for pictures, videos, and sounds. In this paper, we describe the validation of ten affective interactive Virtual Environments (VEs) designed to be used in Virtual Reality. These environments are related to five emotions. The testing phase included using two different experimental setups to deliver the overall experience. The setup did not include any immersive VR technology, because of the ongoing COVID-19 pandemic, but the VEs were designed to run on stereoscopic visual displays. We collected measures related to the participants' emotional experience based on six discrete emotional categories plus neutrality and we included an assessment of the sense of presence related to the different experiences. The results showed how the scenarios can be differentiated according to the emotion aroused. Finally, the comparison between the two experimental setups demonstrated high reliability of the experience and strong adaptability of the scenarios to different contexts of use.


Assuntos
Nível de Alerta/fisiologia , COVID-19/psicologia , Bases de Dados Factuais/estatística & dados numéricos , Emoções/fisiologia , SARS-CoV-2/isolamento & purificação , Realidade Virtual , Adulto , COVID-19/epidemiologia , COVID-19/virologia , Emoções/classificação , Empatia , Feminino , Humanos , Masculino , Pandemias/prevenção & controle , Estimulação Luminosa/métodos , Reprodutibilidade dos Testes , SARS-CoV-2/fisiologia , Adulto Jovem
17.
Sci Rep ; 11(1): 24171, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921175

RESUMO

The transmission of COVID-19 is dependent on social mixing, the basic rate of which varies with sociodemographic, cultural, and geographic factors. Alterations in social mixing and subsequent changes in transmission dynamics eventually affect hospital admissions. We employ these observations to model and predict regional hospital admissions in Sweden during the COVID-19 pandemic. We use an SEIR-model for each region in Sweden in which the social mixing is assumed to depend on mobility data from public transport utilisation and locations for mobile phone usage. The results show that the model could capture the timing of the first and beginning of the second wave of the pandemic 3 weeks in advance without any additional assumptions about seasonality. Further, we show that for two major regions of Sweden, models with public transport data outperform models using mobile phone usage. We conclude that a model based on routinely collected mobility data makes it possible to predict future hospital admissions for COVID-19 3 weeks in advance.


Assuntos
Algoritmos , COVID-19/transmissão , Telefone Celular/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Modelos Teóricos , Admissão do Paciente/estatística & dados numéricos , COVID-19/epidemiologia , COVID-19/virologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , Previsões/métodos , Geografia , Hospitalização/tendências , Humanos , Pandemias/prevenção & controle , Admissão do Paciente/tendências , Estudos Retrospectivos , SARS-CoV-2/fisiologia , Suécia/epidemiologia , Viagem/estatística & dados numéricos
18.
Sci Rep ; 11(1): 24145, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921180

RESUMO

Recent studies suggest that coronaviruses circulate widely in Southeast Asian bat species and that the progenitors of the SARS-Cov-2 virus could have originated in rhinolophid bats in the region. Our objective was to assess the diversity and circulation patterns of coronavirus in several bat species in Southeast Asia. We undertook monthly live-capture sessions and sampling in Cambodia over 17 months to cover all phases of the annual reproduction cycle of bats and test specifically the association between their age and CoV infection status. We additionally examined current information on the reproductive phenology of Rhinolophus and other bat species presently known to occur in mainland southeast China, Vietnam, Laos and Cambodia. Results from our longitudinal monitoring (573 bats belonging to 8 species) showed an overall proportion of positive PCR tests for CoV of 4.2% (24/573) in cave-dwelling bats from Kampot and 4.75% (22/463) in flying-foxes from Kandal. Phylogenetic analysis showed that the PCR amplicon sequences of CoVs (n = 46) obtained clustered in Alphacoronavirus and Betacoronavirus. Interestingly, Hipposideros larvatus sensu lato harbored viruses from both genera. Our results suggest an association between positive detections of coronaviruses and juvenile and immature bats in Cambodia (OR = 3.24 [1.46-7.76], p = 0.005). Since the limited data presently available from literature review indicates that reproduction is largely synchronized among rhinolophid and hipposiderid bats in our study region, particularly in its more seasonal portions (above 16° N), this may lead to seasonal patterns in CoV circulation. Overall, our study suggests that surveillance of CoV in insectivorous bat species in Southeast Asia, including SARS-CoV-related coronaviruses in rhinolophid bats, could be targeted from June to October for species exhibiting high proportions of juveniles and immatures during these months. It also highlights the need to develop long-term longitudinal surveys of bats and improve our understanding of their ecology in the region, for both biodiversity conservation and public health reasons.


Assuntos
Alphacoronavirus/genética , Betacoronavirus/genética , COVID-19/transmissão , Quirópteros/crescimento & desenvolvimento , SARS-CoV-2/genética , Alphacoronavirus/classificação , Animais , Ásia Sudeste/epidemiologia , Betacoronavirus/classificação , COVID-19/epidemiologia , COVID-19/virologia , Camboja/epidemiologia , Quirópteros/classificação , Quirópteros/virologia , Epidemias/prevenção & controle , Evolução Molecular , Genoma Viral/genética , Geografia , Humanos , Estudos Longitudinais , Masculino , Filogenia , SARS-CoV-2/classificação , SARS-CoV-2/fisiologia , Especificidade da Espécie
19.
Sci Rep ; 11(1): 24183, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921199

RESUMO

COVID-19 has restricted singing in communal worship. We sought to understand variations in droplet transmission and the impact of wearing face masks. Using rapid laser planar imaging, we measured droplets while participants exhaled, said 'hello' or 'snake', sang a note or 'Happy Birthday', with and without surgical face masks. We measured mean velocity magnitude (MVM), time averaged droplet number (TADN) and maximum droplet number (MDN). Multilevel regression models were used. In 20 participants, sound intensity was 71 dB for speaking and 85 dB for singing (p < 0.001). MVM was similar for all tasks with no clear hierarchy between vocal tasks or people and > 85% reduction wearing face masks. Droplet transmission varied widely, particularly for singing. Masks decreased TADN by 99% (p < 0.001) and MDN by 98% (p < 0.001) for singing and 86-97% for other tasks. Masks reduced variance by up to 48%. When wearing a mask, neither singing task transmitted more droplets than exhaling. In conclusion, wide variation exists for droplet production. This significantly reduced when wearing face masks. Singing during religious worship wearing a face mask appears as safe as exhaling or talking. This has implications for UK public health guidance during the COVID-19 pandemic.


Assuntos
COVID-19/transmissão , Transmissão de Doença Infecciosa/prevenção & controle , Face , Máscaras , Canto/fisiologia , Adulto , COVID-19/epidemiologia , COVID-19/virologia , Estudos Transversais , Expiração/fisiologia , Feminino , Humanos , Masculino , Pandemias/prevenção & controle , Fatores de Risco , SARS-CoV-2/fisiologia , Eliminação de Partículas Virais/fisiologia
20.
Sci Rep ; 11(1): 24198, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921220

RESUMO

Certain immunizations including vaccination against tick-borne encephalitis virus (TBEV) have been suggested to confer cross-protection against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Within a prospective healthcare worker (HCW) cohort, we assessed the potentially protective role of anti-TBEV antibodies against SARS-CoV-2 infection. Among 3352 HCW, those with ≥ 1 previous TBEV vaccination (n = 2018, 60%) showed a reduced risk of SARS-CoV-2 seroconversion (adjusted odds ratio: 0.8, 95% CI: 0.7-1.0, P = 0.02). However, laboratory testing of a subgroup of 26 baseline and follow-up samples did not demonstrate any neutralizing effect of anti-TBEV antibodies against SARS-CoV-2 in live-virus neutralization assay. However, we observed significantly higher anti-TBEV antibody titers in follow-up samples of participants with previous TBEV vaccination compared to baseline, both TBEV neutralizing (p = 0.001) and total IgG (P < 0.0001), irrespective of SARS-CoV-2 serostatus. Based on these data, we conclude that the observed association of previous TBEV vaccination and reduced risk of SARS-CoV-2 infection is likely due to residual confounding factors. The increase in TBEV follow-up antibody titers can be explained by natural TBEV exposure or potential non-specific immune activation upon exposure to various pathogens, including SARS-CoV-2. We believe that these findings, although negative, contribute to the current knowledge on potential cross-immunity against SARS-CoV-2 from previous immunizations.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Encefalite Transmitida por Carrapatos/imunologia , Pessoal de Saúde/estatística & dados numéricos , SARS-CoV-2/imunologia , Adulto , COVID-19/epidemiologia , COVID-19/virologia , Proteção Cruzada/imunologia , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Encefalite Transmitida por Carrapatos/virologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Estudos Prospectivos , SARS-CoV-2/fisiologia , Soroconversão , Vacinação
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