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In vivo assessments of influenza A virus (IAV) pathogenicity and transmissibility in ferrets represent a crucial component of many pandemic risk assessment rubrics, but few systematic efforts to identify which data from in vivo experimentation are most useful for predicting pathogenesis and transmission outcomes have been conducted. To this aim, we aggregated viral and molecular data from 125 contemporary IAV (H1, H2, H3, H5, H7, and H9 subtypes) evaluated in ferrets under a consistent protocol. Three overarching predictive classification outcomes (lethality, morbidity, transmissibility) were constructed using machine learning (ML) techniques, employing datasets emphasizing virological and clinical parameters from inoculated ferrets, limited to viral sequence-based information, or combining both data types. Among 11 different ML algorithms tested and assessed, gradient boosting machines and random forest algorithms yielded the highest performance, with models for lethality and transmission consistently better performing than models predicting morbidity. Comparisons of feature selection among models was performed, and highest performing models were validated with results from external risk assessment studies. Our findings show that ML algorithms can be used to summarize complex in vivo experimental work into succinct summaries that inform and enhance risk assessment criteria for pandemic preparedness that take in vivo data into account.
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Hurones , Virus de la Influenza A , Aprendizaje Automático , Infecciones por Orthomyxoviridae , Animales , Hurones/virología , Medición de Riesgo/métodos , Virus de la Influenza A/patogenicidad , Virus de la Influenza A/genética , Virus de la Influenza A/fisiología , Infecciones por Orthomyxoviridae/virología , Infecciones por Orthomyxoviridae/transmisión , Modelos Animales de Enfermedad , AlgoritmosRESUMEN
Ocular inoculation of a clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) virus caused severe and fatal infection in ferrets. Virus was transmitted to ferrets in direct contact. The results highlight the potential capacity of these viruses to cause human disease after either respiratory or ocular exposure.
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Hurones , Subtipo H5N1 del Virus de la Influenza A , Infecciones por Orthomyxoviridae , Animales , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Subtipo H5N1 del Virus de la Influenza A/genética , Infecciones por Orthomyxoviridae/virología , Humanos , Ojo/virología , Gripe Humana/virologíaRESUMEN
Background: At the intersection of neural monitoring and decoding, event-related potential (ERP) based on electroencephalography (EEG) has opened a window into intrinsic brain function. The stability of ERP makes it frequently employed in the field of neuroscience. However, project-specific custom code, tracking of user-defined parameters, and the large diversity of commercial tools have limited clinical application. Methods: We introduce an open-source, user-friendly, and reproducible MATLAB toolbox named EPAT that includes a variety of algorithms for EEG data preprocessing. It provides EEGLAB-based template pipelines for advanced multi-processing of EEG, magnetoencephalography, and polysomnogram data. Participants evaluated EEGLAB and EPAT across 14 indicators, with satisfaction ratings analyzed using the Wilcoxon signed-rank test or paired t-test based on distribution normality. Results: EPAT eases EEG signal browsing and preprocessing, EEG power spectrum analysis, independent component analysis, time-frequency analysis, ERP waveform drawing, and topological analysis of scalp voltage. A user-friendly graphical user interface allows clinicians and researchers with no programming background to use EPAT. Conclusion: This article describes the architecture, functionalities, and workflow of the toolbox. The release of EPAT will help advance EEG methodology and its application to clinical translational studies.
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Data from influenza A virus (IAV) infected ferrets provides invaluable information towards the study of novel and emerging viruses that pose a threat to human health. This gold standard model can recapitulate many clinical signs of infection present in IAV-infected humans, support virus replication of human, avian, swine, and other zoonotic strains without prior adaptation, and permit evaluation of virus transmissibility by multiple modes. While ferrets have been employed in risk assessment settings for >20 years, results from this work are typically reported in discrete stand-alone publications, making aggregation of raw data from this work over time nearly impossible. Here, we describe a dataset of 728 ferrets inoculated with 126 unique IAV, conducted by a single research group under a uniform experimental protocol. This collection of morbidity, mortality, and viral titer data represents the largest publicly available dataset to date of in vivo-generated IAV infection outcomes on a per-ferret level.
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Hurones , Virus de la Influenza A , Infecciones por Orthomyxoviridae , Animales , Modelos Animales de Enfermedad , Hurones/virología , Infecciones por Orthomyxoviridae/virología , Carga ViralRESUMEN
This study aimed to develop and validate a new scale to measure health problem prevention and control strategies employed by medical rescuers fighting epidemics. In Study I, a qualitative study, focus group discussion, and expert panel review were conducted to generate items that capture components of prevention and control strategies. In Study II, exploratory factor analysis was used to examine the scale's structure. In Study III, the scale's validity and reliability were assessed via confirmatory factor analysis, average variance extracted, composite reliability, and Cronbach's α. Data analysis was performed using Nvivo 12.0, SPSS 25.0, and Amos 23.0. The final scale was divided into three subscales (comprising 5 factors and 18 items on the Before Medical Rescue subscale, 6 factors and 28 items on the During Medical Rescue subscale, and 4 factors and 14 items on the After Medical Rescue subscale). The scale has excellent validity and reliability and can be used to measure the health problem prevention and control strategies of medical rescuers fighting epidemics.
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Acute myocardial infarction (MI) is a common and severe cardiovascular emergency that requires immediate treatment. Angina pectoris, which typically signals myocardial ischaemia, can appear in MI cases with myriad causes aside from coronary artery disease. However, not all MI patients benefit from invasive revascularisation therapy. We herein report a case involving a 78-year-old female patient with a complex medical history, including non-ST-segment elevation MI and coronary artery bypass grafting, who experienced recurrent chest pain. Instead of a direct result of coronary artery disease, her chest pain was later found to be primarily induced by atrial fibrillation (AF). Consequently, we shifted the focus of management to effective rate control for the AF after careful evaluation and achieved a satisfactory result. This case highlights the successful identification and timely application of intensive heart rate control management in an MI case induced by AF.
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Fibrilación Atrial , Insuficiencia Cardíaca , Infarto del Miocardio , Humanos , Anciano , Femenino , Fibrilación Atrial/terapia , Fibrilación Atrial/complicaciones , Infarto del Miocardio/complicaciones , Infarto del Miocardio/terapia , Insuficiencia Cardíaca/etiología , Revascularización Miocárdica/métodos , Antiarrítmicos/uso terapéutico , Frecuencia Cardíaca/fisiologíaRESUMEN
Viral pathogenesis and therapeutic screening studies that utilize small mammalian models rely on the accurate quantification and interpretation of morbidity measurements, such as weight and body temperature, which can vary depending on the model, agent and/or experimental design used. As a result, morbidity-related data are frequently normalized within and across screening studies to aid with their interpretation. However, such data normalization can be performed in a variety of ways, leading to differences in conclusions drawn and making comparisons between studies challenging. Here, we discuss variability in the normalization, interpretation, and presentation of morbidity measurements for four model species frequently used to study a diverse range of human viral pathogens - mice, hamsters, guinea pigs and ferrets. We also analyze findings aggregated from influenza A virus-infected ferrets to contextualize this discussion. We focus on serially collected weight and temperature data to illustrate how the conclusions drawn from this information can vary depending on how raw data are collected, normalized and measured. Taken together, this work supports continued efforts in understanding how normalization affects the interpretation of morbidity data and highlights best practices to improve the interpretation and utility of these findings for extrapolation to public health contexts.
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Hurones , Virosis , Cricetinae , Humanos , Animales , Cobayas , Ratones , Reproducibilidad de los Resultados , Mamíferos , MorbilidadRESUMEN
Clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) viruses have caused large outbreaks within avian populations on five continents, with concurrent spillover into a variety of mammalian species. Mutations associated with mammalian adaptation have been sporadically identified in avian isolates, and more frequently among mammalian isolates following infection. Reports of human infection with A(H5N1) viruses following contact with infected wildlife have been reported on multiple continents, highlighting the need for pandemic risk assessment of these viruses. In this study, the pathogenicity and transmissibility of A/Chile/25945/2023 HPAI A(H5N1) virus, a novel reassortant with four gene segments (PB1, PB2, NP, MP) from North American lineage, isolated from a severe human case in Chile, was evaluated in vitro and using the ferret model. This virus possessed a high capacity to cause fatal disease, characterized by high morbidity and extrapulmonary spread in virus-inoculated ferrets. The virus was capable of transmission to naïve contacts in a direct contact setting, with contact animals similarly exhibiting severe disease, but did not exhibit productive transmission in respiratory droplet or fomite transmission models. Our results indicate that the virus would need to acquire an airborne transmissible phenotype in mammals to potentially cause a pandemic. Nonetheless, this work warrants continuous monitoring of mammalian adaptations in avian viruses, especially in strains isolated from humans, to aid pandemic preparedness efforts.
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Hurones , Subtipo H5N1 del Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Animales , Hurones/virología , Humanos , Chile , Gripe Humana/virología , Gripe Humana/transmisión , Infecciones por Orthomyxoviridae/virología , Infecciones por Orthomyxoviridae/transmisión , Infecciones por Orthomyxoviridae/veterinaria , Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Subtipo H5N1 del Virus de la Influenza A/clasificación , Subtipo H5N1 del Virus de la Influenza A/fisiología , Virus Reordenados/genética , Virus Reordenados/aislamiento & purificación , Virus Reordenados/patogenicidad , Virus Reordenados/clasificación , Filogenia , Gripe Aviar/virología , Gripe Aviar/transmisiónRESUMEN
OBJECTIVE: Develop and psychometrically test the physiopsychological disorders scale for medical rescuers fighting epidemics (PDS-MRFE). METHOD: A three-phase approach was used to develop and test the physiopsychological disorders scale: (1) creating the item pool, (2) preliminarily evaluating items, and (3) refining the scale and estimating the psychometric properties. The items of the instrument were generated based on a comprehensive literature review and a qualitative study conducted with 31 medical rescuers (18 nurses and 13 doctors) fighting epidemics. A preliminary evaluation of items was conducted using content validity which was evaluated by a panel of 15 experts. Validity and reliability examinations were conducted to refine the scale and evaluate its psychometric properties. This was done using two different samples. Specifically, Sample A (360 medical rescuers) was employed for item reduction and exploratory factor analysis (EFA), and Sample B (287 medical rescuers) was employed for the confirmatory factor analysis (CFA) and determination of other psychometric properties (i.e., reliability, concurrent, convergent, and discriminant validity), which further confirmed the structure of the scale and evaluated its final psychometric properties. RESULTS: The final scale has 39 items with three subscales, including before, during, and after rescue. The exploratory factor analysis result indicated that the before-rescue scale of four items, during-rescue of 21 items, and after-rescue of 14 items explained 52.07%, 69.75%, and 52.30% of the cumulative variance, respectively. The confirmatory factor analysis result indicated that model fit indices of three subscales were acceptable and showed evidence of adequate content, convergent, discriminate, and concurrent validity. The Cronbach's α coefficients for each subscale and all dimensions ranged from 0.81 to 0.92, indicating good reliability for the PDS-MRFE. CONCLUSIONS: The physiopsychological disorders scale is a psychometrically valid and reliable instrument and can be used in both clinical practice and research to evaluate different physiopsychological disorders at different medical rescue stages among medical rescuers fighting epidemics.
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Epidemias , Humanos , Psicometría , Reproducibilidad de los Resultados , China/epidemiología , Epidemias/prevención & control , Análisis FactorialRESUMEN
As use of the ferret model to study influenza A virus (IAV) pathogenicity increases, periodic assessment of data generated in this model is warranted, to identify features associated with virus replication throughout the respiratory tract and to refine future analyses. However, protocol-specific differences present between independent laboratories limit easy aggregation of virological data. We compiled viral titer and clinical data from >1,000 ferrets inoculated with 125 contemporary IAV under a consistent experimental protocol (including high- and low-pathogenicity avian, swine-origin, and human viruses, spanning H1, H2, H3, H5, H7, and H9 subtypes) and examined which meaningful and statistically supported associations were present among numerous quantitative measurements. Viral titers correlated positively between ferret nasal turbinate tissue, lung tissue, and nasal wash specimens, though the strength of the associations varied, notably regarding the particular nasal wash summary measure employed and properties of the virus itself. Use of correlation coefficients and mediation analyses further supported the interconnectedness of viral titer measurements taken at different sites throughout the respiratory tract. IAV possessing mammalian host adaptation markers in the HA and PB2 exhibited more rapid growth in the ferret upper respiratory tract early after infection, supported by quantities derived from infectious titer data to capture infection progression, compared with viruses bearing hallmarks of avian IAV. Collectively, this work identifies summary metrics most closely linked with virological and phenotypic outcomes in ferrets, supporting continued refinement of data analyzed from in vivo experimentation, notably from studies conducted to evaluate the public health risk posed by novel and emerging IAV.IMPORTANCEFerrets are frequently employed to study the pandemic potential of novel and emerging influenza A viruses. However, systematic retrospective analyses of data generated from these experiments are rarely performed, limiting our ability to identify trends in this data and explore how analyses can be refined. Using logarithmic viral titer and clinical data aggregated from one research group over 20 years, we assessed which meaningful and statistically supported associations were present among numerous quantitative measurements obtained from influenza A virus (IAV)-infected ferrets, including those capturing viral titers, infection progression, and disease severity. We identified numerous linear correlations between parameters assessing virus replication at discrete sites in vivo, including parameters capturing infection progression not frequently employed in the field, and sought to investigate the interconnected nature of these associations. This work supports continued refinement of data analyzed from in vivo experimentation, notably from studies which evaluate the public health risk posed by IAV.
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Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Animales , Humanos , Hurones , Virus de la Influenza A/fisiología , Gripe Humana/virología , Pulmón , Infecciones por Orthomyxoviridae/virología , Porcinos , Modelos Animales de EnfermedadRESUMEN
The sporadic occurrence of human infections with swine-origin influenza A(H3N2) viruses and the continual emergence of novel A(H3N2) viruses in swine herds underscore the necessity for ongoing assessment of the pandemic risk posed by these viruses. Here, we selected 3 recent novel swine-origin A(H3N2) viruses isolated between 2017 to 2020, bearing hemagglutinins from the 1990.1, 2010.1, or 2010.2 clades, and evaluated their ability to cause disease and transmit in a ferret model. We conclude that despite considerable genetic variances, all 3 contemporary swine-origin A(H3N2) viruses displayed a capacity for robust replication in the ferret respiratory tract and were also capable of limited airborne transmission. These findings highlight the continued public health risk of swine-origin A(H3N2) strains, especially in human populations with low cross-reactive immunity.
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Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Enfermedades de los Porcinos , Humanos , Animales , Estados Unidos/epidemiología , Porcinos , Subtipo H3N2 del Virus de la Influenza A/genética , HuronesRESUMEN
IMPORTANCE: Despite the accumulation of evidence showing that airborne transmissible influenza A virus (IAV) typically has a lower pH threshold for hemagglutinin (HA) fusion activation, the underlying mechanism for such a link remains unclear. In our study, by using a pair of isogenic recombinant A(H9N2) viruses with a phenotypical difference in virus airborne transmission in a ferret model due to an acid-destabilizing mutation (HA1-Y17H) in the HA, we demonstrate that an acid-stable A(H9N2) virus possesses a multitude of advantages over its less stable counterpart, including better fitness in the ferret respiratory tract, more effective aerosol emission from infected animals, and improved host susceptibility. Our study provides supporting evidence for the requirement of acid stability in efficient airborne transmission of IAV and sheds light on fundamental mechanisms for virus airborne transmission.
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Glicoproteínas Hemaglutininas del Virus de la Influenza , Subtipo H9N2 del Virus de la Influenza A , Gripe Humana , Animales , Hurones , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/metabolismo , Aerosoles y Gotitas Respiratorias/virología , Gripe Humana/transmisión , Humanos , Modelos Animales de Enfermedad , Sustitución de AminoácidosRESUMEN
The molecular dynamics of pancreatic ductal adenocarcinoma (PDAC) under chemotherapy remain incompletely understood. The widespread use of neoadjuvant chemotherapy (NAC) provides a unique opportunity to investigate PDAC samples post-chemotherapy. Leveraging a cohort from Fudan University Shanghai Cancer Center, encompassing PDAC samples with and without exposure to neoadjuvant albumin-bound paclitaxel and gemcitabine (AG), we have compiled data from single-cell and spatial transcriptomes, proteomes, bulk transcriptomes, and metabolomes, deepening our comprehension of the molecular changes in PDACs in response to chemotherapy. Metabolic flux analysis reveals that NAC induces a reprogramming of PDAC metabolic patterns and enhances immunogenicity. Notably, NAC leads to the downregulation of glycolysis and the upregulation of CD36. Tissue microarray analysis demonstrates that high CD36 expression is linked to poorer survival in patients receiving postoperative AG. Targeting CD36 synergistically improves the PDAC response to AG both in vitro and in vivo, including patient-derived preclinical models.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Terapia Neoadyuvante , Desoxicitidina/farmacología , China , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Neoplasias PancreáticasRESUMEN
OBJECTIVE: This study aimed to investigate the work engagement of clinical nursing teachers and examine whether psychological capital and perceived supervisor social support mediates the association between role stress and work engagement among clinical nursing teachers. DESIGN: A cross-sectional study design was used. SETTING: This study was conducted in five tertiary hospitals affiliated with medical universities in Shandong Province, China. PARTICIPANTS: A total of 412 clinical nursing teachers were recruited out of which 406 completed the questionnaires effectively. METHODS: Questionnaires were administered offline and the items consisted of social demographic characteristics, scale related to role stress, psychological capital, perceived supervisor social support and work engagement. T-tests, one-way analysis of variance and Pearson's correlation analysis were conducted using SPSS, and mediation analysis was performed using structural equation modelling. RESULTS: The work engagement scores of clinical nursing teachers were high, with an average score of 4.76±0.69. Structural equation modelling showed a good fit of the data to the hypothesised model. Role stress did not directly affect work engagement (ß=0.057, p>0.001). However, a strong indirect effect of role stress on work engagement (ß=-0.373, p<0.001) mediated by psychological capital and perceived supervisor social support was observed, with path coefficient of -0.319 (p<0.01) and -0.054 (p<0.01), respectively. The model explains 57% of the variance in work engagement. CONCLUSION: Psychological capital and perceived supervisor social support fully mediated the relationship between role stress and work engagement among clinical nursing teachers. Thus, to promote the work engagement of clinical nursing teachers, their psychological capital needs to be improved. Furthermore, superiors should provide more support, particularly to clinical nursing teachers experiencing high role stress.
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Docentes de Enfermería , Apoyo Social , Compromiso Laboral , Humanos , Estudios Transversales , Pueblos del Este de Asia , Encuestas y Cuestionarios , Universidades , Educación en EnfermeríaRESUMEN
Competition assays were conducted in vitro and in vivo to examine how the Delta (B.1.617.2) variant displaced the prototype Washington/1/2020 (WA/1) strain. While WA/1 virus exhibited a moderately increased proportion compared to that in the inoculum following co-infection in human respiratory cells, Delta variant possessed a substantial in vivo fitness advantage as this virus becoming predominant in both inoculated and contact animals. This work identifies critical traits of the Delta variant that likely played a role in it becoming a dominant variant and highlights the necessities of employing multiple model systems to assess the fitness of newly emerged SARS-CoV-2 variants.
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COVID-19 , Hurones , Animales , Humanos , SARS-CoV-2/genética , BioensayoRESUMEN
Core-needle biopsy (CNB) plays a vital role in the initial diagnosis of breast cancer. However, the complex tissue processing and global shortage of pathologists have hindered traditional histopathology from timely diagnosis on fresh biopsies. In this work, we developed a full digital platform by integrating label-free stimulated Raman scattering (SRS) microscopy with weakly-supervised learning for rapid and automated cancer diagnosis on un-labelled breast CNB. Methods: We first compared the results of SRS imaging with standard hematoxylin and eosin (H&E) staining on adjacent frozen tissue sections. Then fresh unprocessed biopsy tissues were imaged by SRS to reveal diagnostic histoarchitectures. Next, weakly-supervised learning, i.e., the multi-instance learning (MIL) model was conducted to evaluate the ability to differentiate between benign and malignant cases, and compared with the performance of supervised learning model. Finally, gradient-weighted class activation mapping (Grad-CAM) and semantic segmentation were performed to spatially resolve benign/malignant areas with high efficiency. Results: We verified the ability of SRS in revealing essential histological hallmarks of breast cancer in both thin frozen sections and fresh unprocessed biopsy, generating histoarchitectures well correlated with H&E staining. Moreover, we demonstrated that weakly-supervised MIL model could achieve superior classification performance to supervised learnings, reaching diagnostic accuracy of 95% on 61 biopsy specimens. Furthermore, Grad-CAM allowed the trained MIL model to visualize the histological heterogeneity within the CNB. Conclusion: Our results indicate that MIL-assisted SRS microscopy provides rapid and accurate diagnosis on histologically heterogeneous breast CNB, and could potentially help the subsequent management of patients.
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Neoplasias de la Mama , Mama , Humanos , Femenino , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Biopsia/métodos , Eosina Amarillenta-(YS) , Microscopía Óptica no Lineal , Biopsia con AgujaRESUMEN
As influenza A viruses (IAV) continue to cross species barriers and cause human infection, the establishment of risk assessment rubrics has improved pandemic preparedness efforts. In vivo pathogenicity and transmissibility evaluations in the ferret model represent a critical component of this work. As the relative contribution of in vitro experimentation to these rubrics has not been closely examined, we sought to evaluate to what extent viral titer measurements over the course of in vitro infections are predictive or correlates of nasal wash and tissue measurements for IAV infections in vivo. We compiled data from ferrets inoculated with an extensive panel of over 50 human and zoonotic IAV (inclusive of swine-origin and high- and low-pathogenicity avian influenza viruses associated with human infection) under a consistent protocol, with all viruses concurrently tested in a human bronchial epithelial cell line (Calu-3). Viral titers in ferret nasal wash specimens and nasal turbinate tissue correlated positively with peak titer in Calu-3 cells, whereas additional phenotypic and molecular determinants of influenza virus virulence and transmissibility in ferrets varied in their association with in vitro viral titer measurements. Mathematical modeling was used to estimate more generalizable key replication kinetic parameters from raw in vitro viral titers, revealing commonalities between viral infection progression in vivo and in vitro. Meta-analyses inclusive of IAV that display a diverse range of phenotypes in ferrets, interpreted with mathematical modeling of viral kinetic parameters, can provide critical information supporting a more rigorous and appropriate contextualization of in vitro experiments toward pandemic preparedness. IMPORTANCE Both in vitro and in vivo models are employed for assessing the pandemic potential of novel and emerging influenza A viruses in laboratory settings, but systematic examinations of how well viral titer measurements obtained in vitro align with results from in vivo experimentation are not frequently performed. We show that certain viral titer measurements following infection of a human bronchial epithelial cell line are positively correlated with viral titers in specimens collected from virus-inoculated ferrets and employ mathematical modeling to identify commonalities between viral infection progression between both models. These analyses provide a necessary first step in enhanced interpretation and incorporation of in vitro-derived data in risk assessment activities and highlight the utility of employing mathematical modeling approaches to more closely examine features of virus replication not identifiable by experimental studies alone.
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Virus de la Influenza A , Infecciones por Orthomyxoviridae , Medición de Riesgo , Animales , Humanos , Hurones , Virus de la Influenza A/patogenicidad , Gripe Humana , Infecciones por Orthomyxoviridae/patología , Medición de Riesgo/métodos , Porcinos , Replicación Viral , Línea Celular , Técnicas In VitroRESUMEN
The ferret transmission model is routinely used to evaluate the pandemic potential of newly emerging influenza A viruses. However, concurrent measurement of viral load in the air is typically not a component of such studies. To address this knowledge gap, we measured the levels of virus in ferret nasal washes as well as viral RNA emitted into the air for 14 diverse influenza viruses, encompassing human-, swine-, and avian-origin strains. Here we show that transmissible viruses display robust replication and fast release into the air. In contrast, poorly- and non-transmissible viruses show significantly reduced or delayed replication along with lower detection of airborne viral RNA at early time points post inoculation. These findings indicate that efficient ferret-to-ferret transmission via the air is directly associated with fast emission of virus-laden particles; as such, quantification of viral RNA in the air represents a useful addition to established assessments of new influenza virus strains.
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Virus de la Influenza A , Infecciones por Orthomyxoviridae , Humanos , Animales , Porcinos , Hurones , Aves , ARN ViralRESUMEN
Despite reports of confirmed human infection following ocular exposure with both influenza A virus (IAV) and SARS-CoV-2, the dynamics of virus spread throughout oculonasal tissues and the relative capacity of virus transmission following ocular inoculation remain poorly understood. Furthermore, the impact of exposure route on subsequent release of airborne viral particles into the air has not been examined previously. To assess this, ferrets were inoculated by the ocular route with A(H1N1)pdm09 and A(H7N9) IAVs and two SARS-CoV-2 (early pandemic Washington/1 and Delta variant) viruses. Virus replication was assessed in both respiratory and ocular specimens, and transmission was evaluated in direct contact or respiratory droplet settings. Viral RNA in aerosols shed by inoculated ferrets was quantified with a two-stage cyclone aerosol sampler (National Institute for Occupational Safety and Health [NIOSH]). All IAV and SARS-CoV-2 viruses mounted a productive and transmissible infection in ferrets following ocular inoculation, with peak viral titers and release of virus-laden aerosols from ferrets indistinguishable from those from ferrets inoculated by previously characterized intranasal inoculation methods. Viral RNA was detected in ferret conjunctival washes from all viruses examined, though infectious virus in this specimen was recovered only following IAV inoculation. Low-dose ocular-only aerosol exposure or inhalation aerosol exposure of ferrets to IAV similarly led to productive infection of ferrets and shedding of aerosolized virus. Viral evolution during infection was comparable between all inoculation routes examined. These data support that both IAV and SARS-CoV-2 can establish a high-titer mammalian infection following ocular exposure that is associated with rapid detection of virus-laden aerosols shed by inoculated animals. IMPORTANCE Documented human infection with influenza viruses and SARS-CoV-2 has been reported among individuals wearing respiratory protection in the absence of eye protection, highlighting the capacity of these respiratory tract-tropic viruses to exploit nonrespiratory routes of exposure to initiate productive infection. However, comprehensive evaluations of how ocular exposure may modulate virus pathogenicity and transmissibility in mammals relative to respiratory exposure are limited and have not investigated multiple virus families side by side. Using the ferret model, we show that ocular exposure with multiple strains of either coronaviruses or influenza A viruses leads to an infection that results in shedding of detectable aerosolized virus from inoculated animals, contributing toward onward transmission of both viruses to susceptible contacts. Collectively, these studies support that the ocular surface represents a susceptible mucosal surface that, if exposed to a sufficient quantity of either virus, permits establishment of an infection which is similarly transmissible as that following respiratory exposure.
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COVID-19 , Infecciones por Orthomyxoviridae , Animales , Humanos , COVID-19/transmisión , COVID-19/virología , Modelos Animales de Enfermedad , Hurones , Subtipo H1N1 del Virus de la Influenza A , Subtipo H7N9 del Virus de la Influenza A , Infecciones por Orthomyxoviridae/transmisión , Infecciones por Orthomyxoviridae/virología , Aerosoles y Gotitas Respiratorias , ARN Viral/aislamiento & purificación , SARS-CoV-2 , Esparcimiento de VirusRESUMEN
OBJECTIVE: To explore the physical and mental health problems of front-line healthcare workers fighting COVID-19 across the three phases of the epidemic rescue mission (before, during and after) in China. DESIGN: A qualitative study was adopted using face to face, in-depth semistructured interviews. Phenomenological research methods and Colaizzi's seven-step analysis method were used in the study. SETTING: The setting of the study was the offices of healthcare workers in 12 tertiary hospitals. PARTICIPANTS: Thirty-one front-line healthcare workers from 16 provinces in China, who carried out rescue missions in Hubei Province, were interviewed from October to November 2020. RESULTS: Physical and mental health problems existed before, during and after the COVID-19 rescue mission. Eleven themes emerged during the three phases. Two themes appeared before rescue mission: basic diseases, anxiety before rescue mission. Five themes appeared during rescue mission: basic physical function disorder, physical exhaustion, negative cognition, negative emotions and negative behaviour. Four themes appeared after rescue mission: physical dysfunction, negative emotions, stigmatisation and hypochondriasis. CONCLUSION: Both physical and mental health problems occurred throughout the three phases. The study results pointed that a comprehensive prevention and control system that addresses both physical and mental health problems of front-line healthcare workers throughout the three phases of epidemic rescue mission (before, during and after), and that involves themselves, their families, hospitals, the government and social organisations is needed.