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COVID-19/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Fator de Necrose Tumoral alfa/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Genoma Viral , Humanos , Interleucina-6/análise , Masculino , Pessoa de Meia-Idade , Sistema Respiratório/química , Sistema Respiratório/virologia , Adulto JovemRESUMO
BACKGROUND: Whether acute respiratory illnesses (ARIs), often associated with virus detection, are associated with lower risk for subsequent ARI remains unclear. We assessed the association between symptomatic ARI and subsequent ARI in young children. METHODS: In a prospective cohort of Peruvian children <3 years, we examined the impact of index ARI on subsequent ARI risk. Index ARI were matched with ≤3 asymptomatic observations and followed over 28 days. We compared risk of subsequent ARI between groups using conditional logistic regression adjusting for several covariates, accounting for repeat observations from individual children. RESULTS: Among 983 index ARI, 339 (34%) had an ARI event during follow-up, compared with 876/2826 (31%) matched asymptomatic observations. We found no significant association of index ARI and subsequent ARI risk during follow-up overall (adjusted odds ratio [aOR], 1.10; 95% confidence interval [CI], .98-1.23) or when limited to index ARI with respiratory viruses detected (aOR, 1.03; 95% CI, .86-1.24). Similarly, when the outcome was limited to ARI in which viruses were detected, no significant association was seen (aOR, 1.05; 95% CI, .87-1.27). CONCLUSIONS: ARIs were not associated with short-term protection against subsequent ARI in these children. Additional longitudinal studies are needed to understand drivers of recurrent ARI in young children.
Assuntos
Sistema Respiratório/virologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Viroses/diagnóstico , Viroses/virologia , Vírus/isolamento & purificação , Doença Aguda , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Peru/epidemiologia , Estudos Prospectivos , Interferência ViralRESUMO
There is a paucity of reports on the characteristics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in infants, because most studies have grouped infants with older children. We analyzed the viral loads of 45318 SARS-CoV-2-positive nasopharyngeal swab samples obtained in Buenos Aires, Argentina. Infants younger than 6 months presented higher viral loads than any other age group. Children older than 6 months showed significantly lower viral loads, similar to those founds in adults. This observation raises new questions regarding the role of infants in the spreading of SARS-CoV-2 infection.
Assuntos
COVID-19 , Sistema Respiratório/virologia , SARS-CoV-2 , Carga Viral , Argentina/epidemiologia , COVID-19/diagnóstico , Humanos , Lactente , SARS-CoV-2/isolamento & purificaçãoRESUMO
The knowledge on the deposition and retention of the viral particle of SARS-CoV-2 in the respiratory tract during the very initial intake from the ambient air is of prime importance to understand the infectious process and COVID-19 initial symptoms. We propose to use a modified version of a widely tested lung deposition model developed by the ICRP, in the context of the ICRP Publication 66, that provides deposition patterns of microparticles in different lung compartments. In the model, we mimicked the "environmental decay" of the virus, determined by controlled experiments related to normal speeches, by the radionuclide 11C that presents comparable decay rates. Our results confirm clinical observations on the high virus retentions observed in the extrathoracic region and the lesser fraction on the alveolar section (in the order of 5), which may shed light on physiopathology of clinical events as well on the minimal inoculum required to establish infection.
Assuntos
COVID-19/virologia , SARS-CoV-2/fisiologia , Aerossóis/análise , COVID-19/metabolismo , Radioisótopos de Carbono , Humanos , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Modelos Biológicos , Sistema Respiratório/metabolismo , Sistema Respiratório/virologiaRESUMO
Resumen Objetivo: Analizar la evidencia sobre la relación entre la contaminación del aire y un riesgo mayor de morbimortalidad por Covid-19. Material y métodos: Se utilizó una adaptación de la metodología de revisiones rápidas de Cochrane. La búsqueda se realizó en PubMed y MedRxiv y se limitó hasta el 28 y 26 de abril, respectivamente. Los títulos y resúmenes fueron revisados por cinco investigadores que, a su vez, revisaron los textos completos de la selección final. Resultados: Se encontraron 450 manuscritos, 15 cumplieron los criterios de inclusión. La evidencia encontrada reporta que la incidencia y el riesgo de morbilidad y mortalidad por Covid-19 se incrementan con la exposición crónica y aguda a la contaminación del aire, particularmente a material particulado (PM2.5, PM10) y dióxido de nitrógeno. Conclusiones: Se requieren más estudios especialmente en ciudades latinoamericanas. Es necesario fortalecer las recomendaciones en las ciudades con mayores niveles de contaminantes y reducir sus emisiones.
Abstract Objective: To analyze the evidence on the relationship between air pollution and an increased risk of morbidity and mortality from Covid-19. Materials and methods: An adaptation of the Cochrane rapid review methodology was used. The search was performed in PubMed and MedRxiv and was limited until April 28 and 26, respectively. The titles and abstracts were reviewed by five researchers who, in turn, reviewed the full texts of the final selection. Results: 450 manuscripts were found, 15 met the inclusion criteria. The evidence reports that the incidence and risk of morbidity and mortality from Covid-19 increase with chronic and acute exposure to air pollution, particularly to particulate matter (PM2.5, PM10) and nitrogen dioxide. Conclusions: More studies are required especially in Latin American cities. It is necessary to strengthen the recommendations in cities with higher levels of pollutants and to reduce their emissions.
Assuntos
Humanos , Pneumonia Viral/epidemiologia , Infecções por Coronavirus/epidemiologia , Poluição do Ar/efeitos adversos , Pandemias , Betacoronavirus , Pneumonia Viral/etiologia , Sistema Respiratório/fisiopatologia , Sistema Respiratório/virologia , Monitoramento Ambiental , Saúde da População Urbana , Incidência , Cidades , Infecções por Coronavirus/etiologia , Síndrome Respiratória Aguda Grave/etiologia , Síndrome Respiratória Aguda Grave/mortalidade , Poluentes Atmosféricos/efeitos adversos , Suscetibilidade a Doenças , Exposição Ambiental , Material Particulado/efeitos adversos , SARS-CoV-2 , COVID-19 , América Latina/epidemiologia , Conceitos MeteorológicosRESUMO
OBJECTIVE: To analyze the evidence on the relationship between air pollution and an increased risk of morbidity and mortality from Covid-19. MATERIALS AND METHODS: An adaptation of the Cochrane rapid review methodology was used. The search was performed in PubMed and MedRxiv and was limited until April 28 and 26, respectively. The titles and abstracts were reviewed by five researchers who, in turn, reviewed the full texts of the final selection. RESULTS: 450 manuscripts were found, 15 met the inclusion criteria. The evidence reports that the incidence and risk of morbidity and mortality from Covid-19 increase with chronic and acute exposure to air pollution, particularly to particulate matter (PM2.5, P M10) and nitrogen dioxide. CONCLUSIONS: More studies are required especially in Latin American cities. It is necessary to strengthen the recommendations in cities with higher levels of pollutants and to reduce their emissions.
OBJETIVO: Analizar la evidencia sobre la relación entre la contaminación del aire y un riesgo mayor de morbimor-talidad por Covid-19. MATERIAL Y MÉTODOS: Se utilizó una adaptación de la metodología de revisiones rápidas de Cochrane. La búsqueda se realizó en PubMed y MedRxiv y se limitó hasta el 28 y 26 de abril, respectivamente. Los títu-los y resúmenes fueron revisados por cinco investigadores que, a su vez, revisaron los textos completos de la selección final. RESULTADOS: Se encontraron 450 manuscritos, 15 cumplieron los criterios de inclusión. La evidencia encon-trada reporta que la incidencia y el riesgo de morbilidad y mortalidad por Covid-19 se incrementan con la exposición crónica y aguda a la contaminación del aire, particularmente a material particulado (PM2.5, P M10) y dióxido de nitrógeno. CONCLUSIONES: Se requieren más estudios especialmente en ciudades latinoamericanas. Es necesario fortalecer las recomendaciones en las ciudades con mayores niveles de contaminantes y reducir sus emisiones.
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Poluição do Ar/efeitos adversos , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Poluentes Atmosféricos/efeitos adversos , COVID-19 , Cidades , Infecções por Coronavirus/etiologia , Suscetibilidade a Doenças , Exposição Ambiental , Monitoramento Ambiental , Humanos , Incidência , América Latina/epidemiologia , Conceitos Meteorológicos , Material Particulado/efeitos adversos , Pneumonia Viral/etiologia , Sistema Respiratório/fisiopatologia , Sistema Respiratório/virologia , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/etiologia , Síndrome Respiratória Aguda Grave/mortalidade , Saúde da População UrbanaRESUMO
Production of antimicrobial peptides cathelicidins, interferons and cytokines is an important feature in airway epithelial host defense. The innate immune response to alpha-herpesvirus infection at the sites of primary replication has not been fully studied. Thus, the aim of this study was to determine the expression of innate immune components, cathelicidins, IFNß, TNFα and TNF receptors (TNFRI and TNFRII) during acute infection and reactivation of bovine herpesvirus type 1 (BoHV-1) and 5 (BoHV-5) in the respiratory tract and lymphoid tissue of their natural host. We found that BoHV infection modulates mainly the expression of BMAP28, a key cathelicidin in cattle. It was downregulated by both viruses in retropharyngeal lymph nodes of acutely infected-calves, and it was accompanied by a lower expression of IFNß, TNFα and TNFRI. BoHV-5 showed a pronounced role in the downregulation of BMAP28, even in nasal mucosa and lung. However, during reactivation, BoHV-5 upregulated both BMAP28 and IFNß in retropharyngeal lymph nodes. Acute replication induced also TNFα mRNA and protein synthesis, and expression of TNFRI and II was positively regulated during both acute infection and reactivation, particularly in the trachea. Moreover, BMAP27 was detected during BoHV-1 reactivation suggesting a potential role at this stage. Thus, cathelicidins are implicated in alpha-herpesvirus infections of the bovine respiratory system and the response is distinct during BoHV-1 and BoHV-5 acute infection and reactivation. This demonstrates that these viruses modulate differentially the components of innate immune response, possibly influencing their pathogenesis. This study provides an initial pilot analysis of factors that might be implicated in alpha-herpesvirus infection of the bovine respiratory system.
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Catelicidinas/imunologia , Doenças dos Bovinos/imunologia , Infecções por Herpesviridae/imunologia , Herpesvirus Bovino 1/imunologia , Interferon beta/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Bovinos , Citocinas/imunologia , Infecções por Herpesviridae/veterinária , Imunidade Inata/imunologia , Projetos Piloto , RNA Mensageiro/imunologia , Receptores do Fator de Necrose Tumoral/imunologia , Sistema Respiratório/imunologia , Sistema Respiratório/virologia , Regulação para Cima/imunologiaRESUMO
The human respiratory syncytial virus (hRSV) remains one of the leading pathogens causing acute respiratory tract infections (ARTIs) in children younger than 2 years old, worldwide. Hospitalizations during the winter season due to hRSV-induced bronchiolitis and pneumonia increase every year. Despite this, there are no available vaccines to mitigate the health and economic burden caused by hRSV infection. The pathology caused by hRSV induces significant damage to the pulmonary epithelium, due to an excessive inflammatory response at the airways. Cytokines are considered essential players for the establishment and modulation of the immune and inflammatory responses, which can either be beneficial or harmful for the host. The deleterious effect observed upon hRSV infection is mainly due to tissue damage caused by immune cells recruited to the site of infection. This cellular recruitment takes place due to an altered profile of cytokines secreted by epithelial cells. As a result of inflammatory cell recruitment, the amounts of cytokines, such as IL-1, IL-6, IL-10, and CCL5 are further increased, while IL-10 and IFN-γ are decreased. However, additional studies are required to elicit the mediators directly associated with hRSV damage entirely. In addition to the detrimental induction of inflammatory mediators in the respiratory tract caused by hRSV, reports indicating alterations in the central nervous system (CNS) have been published. Indeed, elevated levels of IL-6, IL-8 (CXCL8), CCL2, and CCL4 have been reported in cerebrospinal fluid from patients with severe bronchiolitis and hRSV-associated encephalopathy. In this review article, we provide an in-depth analysis of the role of cytokines secreted upon hRSV infection and their potentially harmful contribution to tissue damage of the respiratory tract and the CNS.
Assuntos
Citocinas/fisiologia , Infecções por Vírus Respiratório Sincicial/patologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Linhagem Celular , Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Citocinas/líquido cefalorraquidiano , Células Epiteliais/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Lactente , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Muco/metabolismo , Prevalência , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/metabolismo , Vírus Sincicial Respiratório Humano/imunologia , Vírus Sincicial Respiratório Humano/patogenicidade , Vírus Sincicial Respiratório Humano/fisiologia , Sistema Respiratório/metabolismo , Sistema Respiratório/patologia , Sistema Respiratório/virologia , Replicação ViralRESUMO
BACKGROUND: Multiple factors are involved in asthma exacerbations, including environmental exposure and viral infections. We aimed to assess the association between severe asthma exacerbations, acute respiratory viral infections and other potential risk factors. METHODS: Asthmatic children aged 4-14 years were enrolled for a period of 12 months and divided into two groups: those with exacerbated asthma (group 1) and non-exacerbated asthma (group 2). Clinical data were obtained and nasopharyngeal samples were collected through nasopharyngeal aspirate or swab and analysed via indirect fluorescent immunoassays to detect influenza A and B viruses, parainfluenza 1-3, adenovirus and respiratory syncytial virus. Rhinovirus was detected via molecular assays. Potential risk factors for asthma exacerbation were identified in univariate and multivariate analyses. RESULTS: In 153 children (group 1: 92; group 2: 61), median age 7 and 8 years, respectively, the rate of virus detection was 87.7%. There was no difference between groups regarding the frequency of virus detection (p = 0.68); however, group 1 showed a lower frequency (19.2%) of inhaled corticosteroid use (91.4%, p < 0.01) and evidence of inadequate disease control. In the multivariate analysis, the occurrence of three or more visits to the emergency room in the past 12 months (IRR = 1.40; p = 0.04) and nonadherence to inhaled corticosteroid (IRR = 4.87; p < 0.01) were the only factors associated with exacerbation. CONCLUSION: Our results suggest an association between asthma exacerbations, poor disease control and nonadherence to asthma medication, suggesting that viruses may not be the only culprits for asthma exacerbations in this population.
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Asma/fisiopatologia , Asma/virologia , Infecções Respiratórias/complicações , Infecções Respiratórias/virologia , Viroses/complicações , Adolescente , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Asma/tratamento farmacológico , Brasil , Criança , Pré-Escolar , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Adesão à Medicação , Análise Multivariada , Análise de Regressão , Sistema Respiratório/virologiaRESUMO
The objective of this study was to evaluate the clinical disease, humoral response and viral distribution of recent Porcine rubulavirus (PorPV) isolates in experimentally infected pigs. Four, 6-piglet (5-days old) groups were employed (G1-84, G2-93, G3-147, and G4-T). Three viral strains were used for the experimental infection: the reference strain LPMV-1984 (Michoacán 1984) and two other strains isolated in 2013, one in Queretaro (Qro/93/2013) and the other in Michoacán (Mich/147/2013). Each strain was genetically characterized by amplification and sequencing of the gene encoding hemagglutinin-neuroamidase (HN). The inoculation was performed through the oronasal and ocular routes, at a dose of 1×106TCID50/ml. Subsequently, the signs were evaluated daily and necropsies were performed on 3 different days post infection (dpi). We recorded all micro- and macroscopic lesions. Organs from the nervous, lymphatic, and respiratory system were analyzed by quantifying the viral RNA load and the presence of the infectious virus. The presence of the viral antigen in organs was evidenced through immunohistochemistry. Seroconversion was evaluated through the use of a hemagglutination inhibition test. In the characterization of gene HN, only three substitutions were identified in strain Mich/147/2013, two in strain LPMV/1984 (fourth passage) and one in strain Qro/93/2013, with respect to reference strain LPMV-84, these changes had not been identified as virulence factors in previously reported strains. Neurological alterations associated with the infection were found in all three experimental groups starting from 3dpi. Groups G1-84 and G3-147 presented the most exacerbated nervous signs. Group G2-93 only presented milder signs including slight motor incoordination, and an increased rectal temperature starting from day 5 post infection (PI). The main histopathological findings were the presence of a mononuclear inflammatory infiltrate (lymphocytic/monocytic) surrounding the ventricles in the brain and focal interstitial pneumonitis with distention of the alveolar sacs in the lungs. PorPV and RNA distribution were identified in the organs of the nervous, lymphatic, and respiratory systems of the piglets analyzed at different times (days 5, 10, and 15 PI). The viral antigen was detected in the brain and lungs in most of the assessed groups. Seroconversion was evident in groups G1-84 and G2-93. Groups G1-84 and G3-147 were the most clinically affected by the experimental infection. Both strains were isolated in the state of Michoacán. The virulence of the new isolates maintains similar characteristics to those reported more than 30 years ago.