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Biosens Bioelectron ; 171: 112679, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33069957


The 2019 SARS CoV-2 (COVID-19) pandemic has illustrated the need for rapid and accurate diagnostic tests. In this work, a multiplexed grating-coupled fluorescent plasmonics (GC-FP) biosensor platform was used to rapidly and accurately measure antibodies against COVID-19 in human blood serum and dried blood spot samples. The GC-FP platform measures antibody-antigen binding interactions for multiple targets in a single sample, and has 100% selectivity and sensitivity (n = 23) when measuring serum IgG levels against three COVID-19 antigens (spike S1, spike S1S2, and the nucleocapsid protein). The GC-FP platform yielded a quantitative, linear response for serum samples diluted to as low as 1:1600 dilution. Test results were highly correlated with two commercial COVID-19 antibody tests, including an enzyme linked immunosorbent assay (ELISA) and a Luminex-based microsphere immunoassay. To demonstrate test efficacy with other sample matrices, dried blood spot samples (n = 63) were obtained and evaluated with GC-FP, yielding 100% selectivity and 86.7% sensitivity for diagnosing prior COVID-19 infection. The test was also evaluated for detection of multiple immunoglobulin isotypes, with successful detection of IgM, IgG and IgA antibody-antigen interactions. Last, a machine learning approach was developed to accurately score patient samples for prior COVID-19 infection, using antibody binding data for all three COVID-19 antigens used in the test.

Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas Biossensoriais/instrumentação , Técnicas de Laboratório Clínico , Infecções por Coronavirus/sangue , Pneumonia Viral/sangue , Anticorpos Antivirais/imunologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Teste em Amostras de Sangue Seco , Desenho de Equipamento , Fluorescência , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Dispositivos Lab-On-A-Chip , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/imunologia , Sensibilidade e Especificidade
Biosens Bioelectron ; 171: 112709, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33075724


Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was classified as a pandemic by the World Health Organization and has caused over 550,000 deaths worldwide as of July 2020. Accurate and scalable point-of-care devices would increase screening, diagnosis, and monitoring of COVID-19 patients. Here, we demonstrate rapid label-free electrochemical detection of SARS-CoV-2 antibodies using a commercially available impedance sensing platform. A 16-well plate containing sensing electrodes was pre-coated with receptor binding domain (RBD) of SARS-CoV-2 spike protein, and subsequently tested with samples of anti-SARS-CoV-2 monoclonal antibody CR3022 (0.1 µg/ml, 1.0 µg/ml, 10 µg/ml). Subsequent blinded testing was performed on six serum specimens taken from COVID-19 and non-COVID-19 patients (1:100 dilution factor). The platform was able to differentiate spikes in impedance measurements from a negative control (1% milk solution) for all CR3022 samples. Further, successful differentiation and detection of all positive clinical samples from negative control was achieved. Measured impedance values were consistent when compared to standard ELISA test results showing a strong correlation between them (R2=0.9). Detection occurs in less than five minutes and the well-based platform provides a simplified and familiar testing interface that can be readily adaptable for use in clinical settings.

Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas Biossensoriais/instrumentação , Técnicas de Laboratório Clínico , Infecções por Coronavirus/sangue , Espectroscopia Dielétrica/instrumentação , Pneumonia Viral/sangue , Anticorpos Antivirais/imunologia , Técnicas Biossensoriais/economia , Técnicas de Laboratório Clínico/economia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/economia , Infecções por Coronavirus/imunologia , Espectroscopia Dielétrica/economia , Impedância Elétrica , Desenho de Equipamento , Humanos , Proteínas Imobilizadas/imunologia , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/imunologia , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia , Fatores de Tempo
J Infect Chemother ; 27(1): 120-122, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32988731


INTRODUCTION: Information on the effectiveness of personal protective equipment (PPE) for preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among healthcare workers (HCWs), especially among HCWs with frequent contact with patients with SARS-CoV-2, is limited. METHODS: We conducted a prospective cohort study on 49 HCWs who worked in close contact with patients with SARS-CoV-2 infection. HCWs had blood samples taken every 2 weeks to test for SARS-CoV-2 antibodies using two different types of assay. RESULTS: Forty-nine participants (31 nurses, 15 doctors, 3 other workers) were enrolled. In total, 112 blood samples are obtained from participants. The median work days in 2 weeks was 9 (interquartile range (IQR): 5-10) days. In a single work day, 30 of the 49 participants (61.5%) had contact with patients with suspected or conformed SARS-CoV-2 at least 8 times, and approximately 60% of participants had more than 10 min of contact with a single patient. The median self-reported compliance to PPE was 90% (IQR: 80-100%). Seven participants tested positive for SARS-CoV-2 antibody using enzyme-linked immunosorbent assay (ELISA); however, none were seropositive for SARS-CoV-2 neutralizing antibody, so the positive ELISA results were assumed to be false-positive. CONCLUSIONS: The study provides evidence that appropriate PPE is sufficient to prevent infection amongHCWs. It is necessary to establish a system that provides a stable supply of PPE for HCWs to perform their duties.

Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Pessoal de Saúde , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Pandemias/prevenção & controle , Equipamento de Proteção Individual , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Adulto , Idoso , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Estudos Prospectivos , Adulto Jovem
Methods Mol Biol ; 2225: 25-38, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33108655


Various systems exist for the robust production of recombinant proteins. However, only a few systems are optimal for human vaccine protein production. Plant-based transient protein expression systems offer an advantageous alternative to costly mammalian cell culture-based systems and can perform posttranslational modifications due to the presence of an endomembrane system that is largely similar to that of the animal cell. Technological advances in expression vectors for transient expression in the last two decades have produced new plant expression systems with the flexibility and speed that cannot be matched by those based on mammalian or insect cell culture. The rapid and high-level protein production capability of transient expression systems makes them the optimal system to quickly and versatilely develop and produce vaccines against viruses such as 2019-nCoV that have sudden and unpredictable outbreaks. Here, expression of antiviral subunit vaccines in Nicotiana benthamiana plants via transient expression is demonstrated.

Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Plantas/imunologia , Pneumonia Viral/prevenção & controle , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/biossíntese , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Vetores Genéticos , Humanos , Plantas/genética , Pneumonia Viral/imunologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia
J Exp Med ; 218(3)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33211088


SARS-CoV-2, the causative agent of COVID-19, has been responsible for over 42 million infections and 1 million deaths since its emergence in December 2019. There are few therapeutic options and no approved vaccines. Here, we examine the properties of highly potent human monoclonal antibodies (hu-mAbs) in a Syrian hamster model of SARS-CoV-2 and in a mouse-adapted model of SARS-CoV-2 infection (SARS-CoV-2 MA). Antibody combinations were effective for prevention and in therapy when administered early. However, in vitro antibody neutralization potency did not uniformly correlate with in vivo protection, and some hu-mAbs were more protective in combination in vivo. Analysis of antibody Fc regions revealed that binding to activating Fc receptors contributes to optimal protection against SARS-CoV-2 MA. The data indicate that intact effector function can affect hu-mAb protective activity and that in vivo testing is required to establish optimal hu-mAb combinations for COVID-19 prevention.

Anticorpos Monoclonais Murinos , Anticorpos Neutralizantes , Anticorpos Antivirais , Betacoronavirus/imunologia , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Animais , Anticorpos Monoclonais Murinos/imunologia , Anticorpos Monoclonais Murinos/farmacologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/farmacologia , Linhagem Celular , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Feminino , Humanos , Mesocricetus , Camundongos , Camundongos Endogâmicos BALB C , Pneumonia Viral/imunologia , Pneumonia Viral/terapia
Washington; Organización Panamericana de la Salud; dic 06, 2020. 10 p.
Não convencional em Espanhol | LILACS | ID: biblio-1140269


Entre el 21 de enero y el 2 de diciembre del 2020,1 los 54 países y territorios de la Región de las Américas notificaron en total 27.145.021 casos confirmados por laboratorio de infección por el SARS-CoV-2 y 732.329 muertes. Treinta y ocho de estos países y territorios con datos disponibles desglosados por edad y sexo notificaron 89% de los casos (24.035.426) y 56,5% de las muertes (413.869). En este grupo de países y territorios, 72% de los casos fueron en personas de 20 a 59 años, y 78% de las muertes notificadas fueron personas de 60 años o más. Si bien no hay diferencia en la proporción de casos por sexo, se observa una mayor tasa de mortalidad en los hombres, que representan 59% del total de muertes

Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Pneumonia Viral/prevenção & controle , Pneumonia Viral/epidemiologia , Vacinas Virais/provisão & distribução , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/epidemiologia , Pandemias/prevenção & controle , Betacoronavirus/imunologia , Acesso a Medicamentos Essenciais e Tecnologias em Saúde , América/epidemiologia , Incidência
Rev. Hosp. Ital. B. Aires (2004) ; 40(4): 233-236, dic. 2020. ilus
Artigo em Espanhol | LILACS | ID: biblio-1145604


Entre el 1 y el 26 de junio se llevó a cabo el estudio de investigación "Encuesta de infección por coronavirus tipo 2 del síndrome respiratorio agudo grave (SARS-CoV-2), nivel comunitario en habitantes de un barrio vulnerable urbano de la ciudad de Buenos Aires", que determinó que un 54,3% de los habitantes del barrio presentaban anticuerpos inmunoglobulina tipo G para SARS-CoV-2. El objetivo de este artículo es proporcionar un ejemplo de un muestreo probabilístico que fue utilizado para estimar la prevalencia de seropositividad en este estudio. (AU)

Between 1st and 26th of june, a research named "Survey of infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), community level in inhabitants of a marginal urban neighborhood of the city of Buenos Aires" was carried on. The study showed that 54.3% of the that 54.3% of the people of the neighborhood had antibodies immunoglobulin type G for SARS-CoV-2. The objective of this article is to provide an example of a probability sampling carried out in the study, to measuring the prevalence of seropositivity. (AU)

Humanos , Pneumonia Viral/epidemiologia , Inquéritos Epidemiológicos/estatística & dados numéricos , Infecções por Coronavirus/epidemiologia , Argentina , Pneumonia Viral/imunologia , Estudos Soroepidemiológicos , Amostragem Aleatória Simples , Prevalência , Infecções por Coronavirus/imunologia , Betacoronavirus/imunologia
Rev. esp. quimioter ; 33(6): 392-398, dic. 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-195990


Los coronavirus (CoVs) son un amplio grupo de virus en el que se encuentra el SARS-CoV-2 (familia Coronaviridae, subfamilia Coronavirinae, género Betacoronavirus y subgénero Sarbecovirus). Sus principales proteínas estructurales son la de membrana (M), la de envoltura (E), la nucleocápside (N) y la espicular (S). La respuesta inmune frente a SARS-CoV-2 implica la vertiente celular y humoral, con anticuerpos neutralizantes potencialmente defensivos fundamentalmente dirigidos frente al antígeno S. Aunque los datos de seroprevalencia se asumen muy frecuentemente como marcadores de protección, no necesariamentelo son. En España se estima que al menos cuatro quintas partes de la población deberían estar inmuno-protegidas para asegurar la inmunidad de grupo. Dada la alta tasa de letalidad por COVID-19, la adquisición de esta protección únicamente mediante el contagio natural no es asumible y se debe abogar por otras medidas como puede ser la inmunización masiva. En la actualidad existen varios prototipos de vacunas (que incluyen virus vivos, vectores virológicos, péptidos y proteínas y ácidos nucleicos) en diversas etapas de evaluación clínica. Se prevé que en breve alguna de estas nuevas vacunas se encuentre ya disponible en el mercado. En este texto se revisan aspectos relacionados con estos asuntos

The coronavirus are a wide group of viruses among that the SARS-CoV-2 is included (family Coronaviridae, subfamily Coronavirinae, genus Betacoronavirus and subgenus Sarbecovirus). Its main structural proteins are the membrane (M), the envelope (E), the nucleocapsid (N) and spike (S). The immune response to SARS-CoV-2 involves the cellular and the humoral sides, with neutralizing antibodies fundamentally directed against the S antigen. Although the seroprevalence data are frequently assumed as protection markers, no necessarily they are. In Spain, it is estimated that, to assure the herd immunity, at least four-fifths of the population should be immunoprotected. Due the high fatality rate of COVID-19, the acquisition of the protection only by the natural infection it not assumable and other measures as the mass immunization are required. Currently, there are several vaccine prototypes (including life virus, viral vectors, peptides and proteins and nucleic acid) in different phase of clinical evaluation. Foreseeably, some of these news vaccines would be soon commercially available. In this text, aspects related to these issues are reviewed

Humanos , Infecções por Coronavirus/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus/imunologia , Vacinação , Vacinas Virais/imunologia , Pandemias , Anticorpos Antivirais/imunologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Ensaios Clínicos como Assunto/classificação , Reações Cruzadas/imunologia , Imunidade Coletiva/imunologia , Imunização , Testes de Neutralização/métodos , Proteínas Estruturais Virais
Rev. esp. quimioter ; 33(6): 410-414, dic. 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-195991


INTRODUCCIÓN: El diagnóstico de la infección por SARSCoV-2 presenta limitaciones. La RT-PCR en frotis nasofaríngeo es la prueba considerada como el patrón oro, aunque puede ofrecer falsos negativos. El objetivo de este trabajo ha sido evaluar la utilidad de repetir el frotis nasofaríngeo en pacientes con resultado negativo en función de las diferentes probabilidades clínicas. MÉTODOS: Estudio observacional retrospectivo de los primeros pacientes ingresados en el Hospital Universitario Marqués de Valdecilla en dos plantas COVID de Medicina Interna durante marzo-abril del 2020. La RT-PCR para la detección de al menos dos dianas de los principales genes (E, N, RdRP, ORFab1) y el test de detección de anticuerpos para la detección de al menos IgG. RESULTADOS: Se analizaron 145 pacientes hospitalizados; 98 (67,5%) con el diagnóstico de SARS-CoV-2. Las variables predictivas independientes de SARS-CoV-2 fueron: contacto epidemiológico con otro paciente COVID-19, presentación clínica como neumonía, ausencia de neumonía en el año previo, inicio de síntomas >7 días al ingreso, ≥2 síntomas -tos, disnea y fiebre- y lactato deshidrogenasa >350 U/L (p < 0,05). Un score basado en estas variables presentó un área bajo la curva ROC (ABC ROC) de 0,89 (IC95 0,831-0,946; p < 0,001). El rendimiento de la RT-PCR en su primera determinación fue del 54,9%. La repetición de la prueba permitió detectar un 16% de casos adicionales. El rendimiento global de sucesivas RT-PCR en pacientes con baja probabilidad clínica fue inferior al 5%. CONCLUSIÓN: Hemos definido un score de probabilidad pre-prueba basado en datos epidemiológicos y clínicos con una buena precisión para el diagnóstico por infección SARSCoV-2. La repetición del frotis nasofaríngeo puede evitar errores de muestreo sólo en escenarios de intermedia-alta probabilidad clínica pre-prueba

BACKGROUND: The diagnosis of SARS-CoV-2 infection presents some limitations. RT-PCR in nasopharyngeal swabs is considered the gold standard for the diagnosis, although it can have false negative results. We aimed to analyze the accuracy of repeating nasopharyngeal swabs based on different clinical probabilities. METHODS: Retrospective observational study of the first patients admitted to a two COVID Internal Medicine wards at the University Hospital Marqués de Valdecilla, Santander, from March to April 2020. RT-PCR targering E, N, RdRP and ORFab1 genes and antibody tests detecting IgG. RESULTS: A total of 145 hospitalized patients with suspected SARS-Cov2 infection were admitted and in 98 (67.5%) diagnosis was confirmed. The independent predictive variables for SARS-CoV-2 infection were: epidemiological contact, clinical presentation as pneumonia, absence of pneumonia in the last year, onset of symptoms > 7 days, two or more of the following symptoms -dyspnea, cough or fever- and serum lactate dehydrogenase levels >350 U/L (p < 0.05). A score based on these variables yielded an AUC-ROC of 0.89 (CI95%, 0.831-0.946; p < 0.001). The accuracy of the first nasopharyngeal swabs was 54.9%. Repeating nasopharyngeal swabs two or three times allows to detect an additional 16% of positive cases. The overall accuracy of successive RT-PCR tests in patients with low pre-test probability was <5%. CONCLUSIONS: We have defined a pre-test probability score based on epidemiological and clinical data with a high accuracy for diagnosis of SARS-CoV-2. Repeating nasopharyngeal swabs avoids sampling errors, but only in medium of high probability pre-test clinical scenarios

Humanos , Masculino , Feminino , Idoso , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Betacoronavirus/isolamento & purificação , Pandemias , Anticorpos Antivirais/análise , Área Sob a Curva , Distribuição de Qui-Quadrado , Genes Virais , Nasofaringe/virologia , Probabilidade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Betacoronavirus/genética , Betacoronavirus/imunologia
Rev. esp. quimioter ; 33(6): 415-421, dic. 2020. tab
Artigo em Inglês | IBECS | ID: ibc-195992


INTRODUCTION: The aim of this study is to assess the value of systematic screening in asymptomatic women admitted for spontaneous delivery with a combination of reverse transcription polymerase chain reaction (RT-PCR) and cycle threshold (Ct) and serum antibodies. MATERIAL AND METHODS: Since May 6 all women admitted for spontaneous delivery underwent RT-PCR in nasopharyngeal swabs and specific antibodies IgG of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in serum that were performed as part of routine clinical care in our institution. Ct of the PCR was recorded. We analyzed the first 100 women consecutively admitted for spontaneous delivery at our institution. RESULTS: Nine women were positive for SARS-CoV-2 in nasopharyngeal samples (9%) and 13 (13%) presented positive specific antibodies of the coronavirus. Overall, SARS-CoV-2 prior exposure was 15%. The Ct determination (RT-PCR test) of our 9 positive patients ranged from 36 to 41 cycles with a median of 40. Vaginal delivery occurred in 94% of the cases and only 6% underwent a cesarean section, always for obstetric reasons. No fetal transmission was observed and maternal and neonatal prognosis was excellent. CONCLUSIONS: During epidemic episodes in asymptomatic women in labor, universal testing with RT-PCR (considering Ct determination), and the detection of antibodies, permits a better interpretation of the results and avoid unnecessary isolation procedures

OBJETIVO: El objetivo de este estudio es evaluar, en mujeres asintomáticas que acuden a urgencias en trabajo de parto, el valor de la detección sistemática con una combinación de reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR) y umbral del ciclo (Ct) y anticuerpos séricos. MATERIAL Y MÉTODOS: Desde el 6 de mayo, todas las mujeres ingresadas para parto espontáneo se sometieron a RT-PCR en hisopos nasofaríngeos y anticuerpos específicos IgG del síndrome respiratorio agudo severo por coronavirus 2 (SARS-CoV-2) en suero que se realizaron como parte de la atención clínica de rutina en nuestra institución. Se registró el Ct de la PCR. Analizamos las primeras 100 mujeres admitidas consecutivamente para parto espontáneo en nuestra institución. RESULTADOS: Nueve mujeres fueron positivas para SARS-CoV-2 en muestras nasofaríngeas (9%) y 13 (13%) presentaron anticuerpos específicos positivos del coronavirus. En general, la exposición previa a SARS-CoV-2 fue del 15%. La determinación de Ct (prueba de RT-PCR) de nuestros 9 pacientes positivos varió de 36 a 41 ciclos con una mediana de 40. El parto vaginal se produjo en el 94% de los casos y solo el 6% se sometió a una cesárea, siempre por razones obstétricas. No se observó transmisión fetal y el pronóstico materno y neonatal fue excelente. CONCLUSIONES: Durante los episodios epidémicos en mujeres asintomáticas en trabajo de parto, las pruebas universales con RT-PCR (considerando la determinación de Ct) y la detección de anticuerpos, permiten una mejor interpretación de los resultados y evitan procedimientos de aislamiento innecesarios

Humanos , Feminino , Gravidez , Adolescente , Adulto Jovem , Adulto , Infecções por Coronavirus/diagnóstico , Betacoronavirus/imunologia , Pneumonia Viral/diagnóstico , Infecções Assintomáticas , Pandemias , Complicações Infecciosas na Gravidez/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Anticorpos Antivirais/sangue , Imunoglobulina G/sangue , Nasofaringe/virologia , Programas de Rastreamento , Parto
Rev. esp. quimioter ; 33(6): 422-429, dic. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-195993


INTRODUCCIÓN: Desde el descubrimiento del virus SARSCoV-2 la técnica de reacción en cadena de la polimerasa (RT-PCR) se ha convertido en el método fundamental para el diagnóstico de la enfermedad en su fase aguda. El objetivo es describir la serie basada en la demanda de determinaciones de RT-PCR recibidas en un Servicio de Microbiología en un hospital de tercer nivel de referencia durante tres meses desde el inicio de la epidemia por SARS-CoV-2. MATERIAL Y MÉTODOS: Se realizó un análisis retrospectivo del total de las RT-PCR solicitadas en el servicio de microbiología analizado desde el 25 de febrero de 2020 al 26 de mayo de 2020 (90 días). Se agruparon por semanas epidemiológicas y servicio peticionario. Se realizó un análisis descriptivo por edad, género y número de solicitudes por paciente. Se consideró significativo un nivel de confianza del 95% (p < 0.05). RESULTADOS: Se recibieron un total de 27.106 de solicitudes que correspondían a 22.037 pacientes. Edad mediana 53,7 (RIC 40,9-71,7) años, mujeres: 61,3%. Proporción de pacientes con alguna RT-PCR positiva: 14%. Del total de peticiones de RT-PCR fueron positivas 3.710. La rentabilidad máxima fue la semana epidemiológica 13, con un 39,0%. El servicio peticionario que más RT-PCR ha solicitado de forma global ha sido atención primaria con 15.953 solicitudes. Pacientes con 3 o más RT-PCR: 565, de ellos, 19 pacientes presentaron un resultado positivo tras haber sido negativos. CONCLUSIONES: Las solicitudes han ido aumentando en función de la evolución de la epidemia. La RT-PCR posee un elevado rendimiento diagnóstico en las fases de mayor contagiosidad y/o transmisibilidad del virus

INTRODUCTION: Since the discovery of the SARS-CoV-2 virus, the polymerase chain reaction technique (RT-PCR) has become the fundamental method for diagnosing the disease in its acute phase. The objective is to describe the demand-based series of RT-PCR determinations received at a Microbiology Service at a third-level reference hospital for a health area for three months spanning from the onset of the epidemic by SARS-CoV-2. METHODS: A retrospective analysis of the total of the RT-PCR requested in the Microbiology Service analyzed from 02/25/2020 to 05/26/2020 (90 days) has been carried out. They have been grouped by epidemiological weeks and by the petitioner service. A descriptive analysis was carried out by age, gender and number of requests for each patient. In the tests carried out, a confidence level of 95% (p <0.05) was considered significant. RESULTS: A total of 27,106 requests was received corresponding to 22,037 patients. Median age 53.7 (RIC 40.9-71.7) years, women: 61.3%. Proportion of patients with any positive RT-PCR: 14%. Of the total requests for RT-PCR, positive 3,710. Week 13 had the highest diagnosis performance (39.0%). The primary care has been the service thar has made the most requests (15,953). Patients with 3 or more RT-PCR: 565, of them, 19 patients had a positive result after previously having a negative one. CONCLUSIONS: Requests have been increasing depending on the evolution of the epidemic. The RT-PCR has a high diagnostic performance in the phases of highest contagiousness and / or transmissibility of the virus

Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Pandemias , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Testes Imediatos , Fatores de Risco , Estudos Soroepidemiológicos , Espanha/epidemiologia , Prevalência
Rev. esp. quimioter ; 33(6): 466-484, dic. 2020. ilus, tab, mapas, graf
Artigo em Espanhol | IBECS | ID: ibc-195995


La alta transmisibilidad del SARS-CoV-2 antes y poco después de la aparición de los síntomas sugiere que sólo diagnosticar y aislar a pacientes sintomáticos puede no ser suficiente para interrumpir la propagación de la infección; por ello son también necesarias medidas de salud pública como el distanciamiento social. Adicionalmente será importante detectar a los nuevos infectados que permanecen asintomáticos, que pueden ascender al 50% o más de los casos. Las técnicas moleculares son el patrón de referencia para el diagnóstico de infección por SARS-CoV-2. Sin embargo, el uso masivo de estas técnicas ha generado algunos problemas. Por un lado, la escasez de los recursos (analizadores, fungibles y reactivos), y por otro el retraso en la notificación de resultados. Estos dos hechos se traducen en un retraso en la aplicación de las medidas de aislamiento entre casos y contactos, lo que favorece la expansión de la infección. Las pruebas de detección de antígenos son también métodos de diagnóstico directo, con la ventaja de obtener el resultado en pocos minutos y en el mismo lugar de atención. Además, la sencillez y el bajo coste de estas pruebas permiten repetirlas en días sucesivos en determinados contextos clínicos. La sensibilidad de las pruebas de antígenos es generalmente menor que la de las que detectan ácidos nucleicos, si bien su especificidad es comparable. Se ha comprobado que las pruebas antigénicas tienen más validez en los días alrededor del inicio de síntomas, cuando la carga viral en nasofaringe es mayor. Disponer de un análisis de detección viral rápido y en tiempo real como la prueba de antígenos se ha demostrado más útil para controlar la expansión de la infección que pruebas más sensibles, pero de mayor coste y tiempo de respuesta, como son las pruebas moleculares. Las principales instituciones sanitarias como la OMS, los CDC y el propio Ministerio de Sanidad del Gobierno de España plantean el uso de las pruebas antigénicas en una amplia variedad de estrategias para responder a la pandemia. El presente documento pretende servir de apoyo a los médicos implicados en la atención de pacientes con sospecha de infección por SC2, en el contexto de una incidencia creciente en España desde septiembre de 2020 que representa ya la segunda onda pandémica de COVID-19

The high transmissibility of SARS-CoV-2 before and shortly after the onset of symptoms suggests that only diagnosing and isolating symptomatic patients may not be sufficient to interrupt the spread of infection; therefore, public health measures such as personal distancing are also necessary. Additionally, it will be important to detect the newly infected individuals who remain asymptomatic, which may account for 50% or more of the cases. Molecular techniques are the "gold standard" for the diagnosis of SARS-CoV-2 infection. However, the massive use of these techniques has generated some problems. On the one hand, the scarcity of resources (analyzers, fungibles and reagents), and on the other the delay in the notification of results. These two facts translate into a lag in the application of isolation measures among cases and contacts, which favors the spread of the infection. Antigen detection tests are also direct diagnostic methods, with the advantage of obtaining the result in a few minutes and at the very "pointof-care". Furthermore, the simplicity and low cost of these tests allow them to be repeated on successive days in certain clinical settings. The sensitivity of antigen tests is generally lower than that of nucleic acid tests, although their specificity is comparable. Antigenic tests have been shown to be more valid in the days around the onset of symptoms, when the viral load in the nasopharynx is higher. Having a rapid and real-time viral detection assay such as the antigen test has been shown to be more useful to control the spread of the infection than more sensitive tests, but with greater cost and response time, such as in case of molecular tests. The main health institutions such as the WHO, the CDC and the Ministry of Health of the Government of Spain propose the use of antigenic tests in a wide variety of strategies to respond to the pandemic. This document aims to support physicians involved in the care of patients with suspected SC2 infection, in the context of a growing incidence in Spain since September 2020, which already represents the second pandemic wave of COVID-19

Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pandemias , Doença Aguda , Distribuição por Idade , Busca de Comunicante , Incidência , Nasofaringe/virologia , Sensibilidade e Especificidade
Mol Biol (Mosk) ; 54(6): 922-938, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33276356


To design an effective and safe vaccine against betacoronaviruses, it is necessary to elicit a combination of strong humoral and cell-mediated immune responses as well as to minimize the risk of antibody-dependent enhancement of viral infection. This phenomenon was observed in animal trials of experimental vaccines against SARS-CoV-1 and MERS-CoV that were developed based on inactivated coronavirus or vector constructs expressing the spike protein (S) of the virion. The substitution and glycosylation of certain amino acids in the antigenic determinants of the S-protein, as well as its conformational changes, can lead to the same effect in a new experimental vaccine against SARS-CoV-2. This review outlines approaches for developing vaccines against the new SARS-CoV-2 coronavirus that are based on non-pathogenic viral vectors. For efficient prevention of infections caused by respiratory pathogens the ability of the vaccine to stimulate mucosal immunity in the respiratory tract is important. Such a vaccine can be developed using non-pathogenic Sendai virus vector, since it can be administered intranasally and induce a mucosal immune response that strengthens the antiviral barrier in the respiratory tract and provides reliable protection against infection. The mucosal immunity and the production of IgA antibodies accompanying its development reduces the likelihood of developing an antibody-dependent infection enhancement, which is usually associated only with immunopathological IgG antibodies.

Anticorpos Facilitadores , Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Vírus Sendai , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais , Animais , Anticorpos Antivirais , Betacoronavirus/imunologia , Humanos , Vírus Sendai/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Virais/genética
Washington; Organización Panamericana de la Salud; nov. 21, 2020. 15 p.
Não convencional em Espanhol | LILACS | ID: biblio-1129660


Después de más de ocho meses de la pandemia de COVID-19 en la Región de las Américas, y con todos los países de las subregiones de América del Norte, América Central y América del Sur (con excepción de Uruguay) reportando transmisión comunitaria, los sistemas de salud están siendo sometidos a constantes desafíos y las actividades de inmunización de rutina se están posponiendo en la mayoría de los países. La pandemia ha comprometido el cumplimiento de los indicadores de vigilancia integrada de sarampión / rubéola y Parálisis Flácida Aguda (PFA). Por otro lado, las restricciones impuestas a la circulación de las personas, así como el temor de las personas por adquirir la infección, han limitado las actividades de atención primaria de la salud, incluidos los servicios de prevención, como la vacunación. Las restricciones de movimiento también tuvieron un impacto en la aparición de brotes de enfermedades prevenibles por vacunación (EPV) y / o contribuyeron a la interrupción de la transmisión de estas enfermedades. Sin embargo, la reactivación de las actividades económicas y de las fronteras puede volver a incrementar el riesgo, el cual puede ser aún mayor, dado el impacto de la COVID-19 en la capacidad de los sistemas de salud. A la luz de esta situación y considerando estos factores, se alerta sobre el riesgo de la ocurrencia en las Américas de nuevos brotes de enfermedades prevenibles por vacunación, de diversa magnitud y se considera que el riesgo para la Región es muy alto.

Humanos , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Betacoronavirus/imunologia , Doenças Preveníveis por Vacina/prevenção & controle , América/epidemiologia , Cobertura Vacinal
Cell Death Dis ; 11(11): 957, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33159040


A global effort is currently undertaken to restrain the COVID-19 pandemic. Host immunity has come out as a determinant for COVID-19 clinical outcomes, and several studies investigated the immune profiling of SARS-CoV-2 infected people to properly direct the clinical management of the disease. Thus, lymphopenia, T-cell exhaustion, and the increased levels of inflammatory mediators have been described in COVID-19 patients, in particular in severe cases1. Age represents a key factor in COVID-19 morbidity and mortality2. Understanding age-associated immune signatures of patients are therefore important to identify preventive and therapeutic strategies. In this study, we investigated the immune profile of COVID-19 hospitalized patients identifying a distinctive age-dependent immune signature associated with disease severity. Indeed, defined circulating factors - CXCL8, IL-10, IL-15, IL-27, and TNF-α - positively correlate with older age, longer hospitalization, and a more severe form of the disease and may thus represent the leading signature in critical COVID-19 patients.

Infecções por Coronavirus/patologia , Citocinas/metabolismo , Pneumonia Viral/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Análise por Conglomerados , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Feminino , Humanos , Imunoglobulina G/sangue , Interleucina-10/metabolismo , Interleucina-8/metabolismo , Tempo de Internação , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/metabolismo
BMC Res Notes ; 13(1): 511, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33160412


OBJECTIVE: To evaluate whether patients with COVID-19 who have tested re-positive with the PCR test for the SARS-CoV-2 virus are infectious is a challenge in the current circumstances. A follow-up survey was conducted with healthcare personnel (HCP) who were exposed to a patient whose PCR test results for SARS-CoV-2 were re-positive 18 days after the initial confirmation of negative PCR results. RESULTS: We studied a total of 15 HCP who had contact exposures (15/15) and aerosol exposures (7/15). None of them tested positive for IgG against SARS-CoV-2 on blood examination. None of them had any symptoms during 10 days of active isolation. All PCR tests conducted using the nasopharyngeal swabs collected from the HCP on day 10 were negative. No apparent infection was found in any of the HCP who had contact exposure with and/or aerosol exposure to the patient whose PCR test results for SARS-CoV-2 were re-positive 18 days after the initial confirmation of negative results of PCR tests for SARS-CoV-2. CLINICAL TRIAL: Trial Registration: No. 170, approved June 10th, 2020 by the ethics committee of Sakai City Medical Center.

Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa do Paciente para o Profissional/estatística & dados numéricos , Pneumonia Viral/transmissão , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase , Adulto Jovem
EBioMedicine ; 61: 103069, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33130396


BACKGROUND: Italy was the first western country to experience a large Coronavirus Disease 2019 (COVID-19) outbreak and the province of Bergamo experienced one of the deadliest COVID-19 outbreaks in the world. Following the peak of the epidemic in mid-March, the curve has slowly fallen thanks to the strict lockdown imposed by the Italian government on 9th March 2020. METHODS: We performed a cross-sectional study to assess the prevalence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in 423 workers in Bergamo province who returned to the workplace after the end of the Italian lockdown on 5th May 2020. To this end, we performed an enzyme-linked immunosorbent assay (ELISA) to detect the humoral response against SARS-CoV-2 and a nasopharyngeal swab to assess the presence of SARS-CoV-2 RNA by real-time reverse transcription polymerase chain reaction (rRT-PCR). As a secondary aim of the study, we validated a lateral flow immunochromatography assay (LFIA) for the detection of anti-SARS-CoV-2 antibodies. FINDINGS: ELISA identified 38.5% positive subjects, of whom 51.5% were positive for both IgG and IgM, 47.3% were positive only for IgG, but only 1.2% were positive for IgM alone. Only 23 (5.4%) participants tested positive for SARS-CoV-2 by rRT-PCR, although with high cycle thresholds (between 34 and 39), indicating a very low residual viral load that was not able to infect cultured cells. All these rRT-PCR positive subjects had already experienced seroconversion. When the ELISA was used as the comparator, the estimated specificity and sensitivity of the rapid LFIA for IgG were 98% and 92%, respectively. INTERPRETATION: the prevalence of SARS-CoV-2 infection in the province of Bergamo reached 38.5%, significantly higher than has been reported for most other regions worldwide. Few nasopharyngeal swabs tested positive in fully recovered subjects, though with a very low SARS-CoV-2 viral load, with implications for infectivity and discharge policies for positive individuals in the post-pandemic period. The rapid LFIA used in this study is a valuable tool for rapid serologic surveillance of COVID-19 for population studies. FUNDING: The study was supported by Regione Lombardia, Milano Serravalle - Milano Tangenziali S.p.A., Brembo S.p.A, and by MEI System.

Anticorpos Antivirais/sangue , Betacoronavirus/genética , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , RNA Viral/metabolismo , Adulto , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral
Cell Rep ; 33(5): 108339, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33147451


Here, we report our studies of immune-mediated regulation of Zika virus (ZIKV), herpes simplex virus 1 (HSV-1), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the human cornea. We find that ZIKV can be transmitted via corneal transplantation in mice. However, in human corneal explants, we report that ZIKV does not replicate efficiently and that SARS-CoV-2 does not replicate at all. Additionally, we demonstrate that type III interferon (IFN-λ) and its receptor (IFNλR1) are expressed in the corneal epithelium. Treatment of human corneal explants with IFN-λ, and treatment of mice with IFN-λ eye drops, upregulates antiviral interferon-stimulated genes. In human corneal explants, blockade of IFNλR1 enhances replication of ZIKV and HSV-1 but not SARS-CoV-2. In addition to an antiviral role for IFNλR1 in the cornea, our results suggest that the human cornea does not support SARS-CoV-2 infection despite expression of ACE2, a SARS-CoV-2 receptor, in the human corneal epithelium.

Betacoronavirus/fisiologia , Córnea/virologia , Infecções por Coronavirus/transmissão , Herpesvirus Humano 1/fisiologia , Interferons/imunologia , Pneumonia Viral/transmissão , Zika virus/fisiologia , Animais , Betacoronavirus/imunologia , Córnea/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Herpes Simples/imunologia , Herpes Simples/transmissão , Herpes Simples/virologia , Humanos , Camundongos , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Replicação Viral/fisiologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
Immunol Res ; 68(6): 325-339, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33161557


Antibodies are considered as an excellent foundation to neutralize pathogens and as highly specific therapeutic agents. Antibodies are generated in response to a vaccine but little use as immunotherapy to combat virus infections. A new generation of broadly cross-reactive and highly potent antibodies has led to a unique chance for them to be used as a medical intervention. Neutralizing antibodies (monoclonal and polyclonal antibodies) are desirable for pharmaceutical products because of their ability to target specific epitopes with their variable domains by precise neutralization mechanisms. The isolation of neutralizing antiviral antibodies has been achieved by Phage displayed antibody libraries, transgenic mice, B cell approaches, and hybridoma technology. Antibody engineering technologies have led to efficacy improvements, to further boost antibody in vivo activities. "Although neutralizing antiviral antibodies have some limitations that hinder their full development as therapeutic agents, the potential for prevention and treatment of infections, including a range of viruses (HIV, Ebola, MERS-COV, CHIKV, SARS-CoV, and SARS-CoV2), are being actively pursued in human clinical trials."

Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Betacoronavirus/imunologia , Infecções por Coronavirus/terapia , Pneumonia Viral/terapia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Infecções por Coronavirus/prevenção & controle , Epitopos/imunologia , Humanos , Imunoterapia/métodos , Camundongos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle