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1.
PLoS One ; 16(7): e0253977, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34214116

RESUMO

SARS-CoV-2 pandemic is causing high morbidity and mortality burden worldwide with unprecedented strain on health care systems. To investigate the time course of the antibody response in relation to the outcome we performed a study in hospitalized COVID-19 patients. As comparison we also investigated the time course of the antibody response in SARS-CoV-2 asymptomatic subjects. Study results show that patients produce a strong antibody response to SARS-CoV-2 with high correlation between different viral antigens (spike protein and nucleoprotein) and among antibody classes (IgA, IgG, and IgM and neutralizing antibodies). The antibody peak is reached by 3 weeks from hospital admission followed by a sharp decrease. No difference was observed in any parameter of the antibody classes, including neutralizing antibodies, between subjects who recovered or with fatal outcome. Only few asymptomatic subjects developed antibodies at detectable levels.


Assuntos
Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Infecções Assintomáticas , COVID-19/imunologia , SARS-CoV-2/imunologia , Idoso , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/mortalidade , Comorbidade , Feminino , Hospitalização , Humanos , Imunoglobulina A/biossíntese , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/biossíntese , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Estudos Retrospectivos
2.
Arch Iran Med ; 24(5): 427-433, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34196209

RESUMO

BACKGROUND: Real-time polymerase chain reaction (RT-PCR) of virus nucleic acid test (NAT) has become the standard method to diagnose severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, there are still many limitations, especially the problem of the high false negative rate. Therefore, the aim of this study was to investigate the positive rate of SARS-CoV-2 NAT and evaluate the diagnostic performance of SARS-CoV-2 IgM and IgG antibody detection in novel coronavirus infection. METHODS: A total of 10309 suspected or high-risk cases of infection with SARS-CoV-2 in Wuhan Hubei, China, were tested for virus NAT by RT-PCR. Among those cases, 762 COVID-19 patients and 143 patients with non-COVID-19 who were tested for SARS-CoV-2 IgM and IgG during the NAT period were screened. The difference between the two test methods was analyzed using the chi-square test. RESULTS: The positive rate of 10309 cases was about 36% (95% CI: 33.39%-39.67%). SARS-CoV-2 was present in various types of specimens, and alveolar lavage fluid had the highest positive rate [52.38% (95% CI: 31.02-73.74)]. The clinical sensitivity of serum SARS-CoV-2 IgM and IgG was 77.17% (588/762) and 94.88% (723/762), respectively, and the clinical specificity was 93.71% (134/143) and 90.21% (129/143). The area under the curve (AUC) of SARS-CoV-2 IgG and combination of IgG with IgM were equally larger than IgM [0.973 (95% CI: 0.964-0.983) vs 0.930 (95% CI: 0.910-0.949)]. IgG antibody had the highest specificity [100.0% (95% CI: 100.00%-100.00%)] and sensitivity [94.0% (95% CI: 92.45%-95.55%)] when detected alone or in combination with IgM antibody. The total coincidence rate of SARS-CoV-2 antibodies detection and SARS-CoV-2 NAT for the diagnosis of SARS-CoV-2 infection was 92.04% (833/905). Among the 34 SARS-CoV-2 NAT-negative patients with clinical symptoms and CT imaging features, 29 (85.29%) patients were positive for SARS-CoV-2 IgM, and 31 (91.76%) were positive for IgG. CONCLUSION: SARS-CoV-2 NAT should be considered for many types of specimens, and the combined test of SARS-CoV-2 IgM and IgG can make up for the problem of missed NAT in COVID-19 patients.


Assuntos
Teste de Ácido Nucleico para COVID-19 , Teste Sorológico para COVID-19 , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , China , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
3.
Nat Commun ; 12(1): 4144, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230476

RESUMO

To investigate the duration of humoral immune response in convalescent coronavirus disease 2019 (COVID-19) patients, we conduct a 12-month longitudinal study through collecting a total of 1,782 plasma samples from 869 convalescent plasma donors in Wuhan, China and test specific antibody responses. The results show that positive rate of IgG antibody against receptor-binding domain of spike protein (RBD-IgG) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the COVID-19 convalescent plasma donors exceeded 70% for 12 months post diagnosis. The level of RBD-IgG decreases with time, with the titer stabilizing at 64.3% of the initial level by the 9th month. Moreover, male plasma donors produce more RBD-IgG than female, and age of the patients positively correlates with the RBD-IgG titer. A strong positive correlation between RBD-IgG and neutralizing antibody titers is also identified. These results facilitate our understanding of SARS-CoV-2-induced immune memory to promote vaccine and therapy development.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Imunoglobulina G/sangue , Receptores Virais/imunologia , SARS-CoV-2/imunologia , Adulto , Animais , Doadores de Sangue , COVID-19/terapia , Linhagem Celular , China , Chlorocebus aethiops , Convalescença , Feminino , Humanos , Imunidade Humoral/imunologia , Imunização Passiva , Memória Imunológica/imunologia , Estudos Longitudinais , Masculino , Fatores Sexuais , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
5.
Cardiovasc Ther ; 2021: 5577218, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239605

RESUMO

Cellular stress response plays an important role in the pathophysiology of coronary artery disease (CAD). Inhibition of cellular stress may provide a novel clinical approach regarding the diagnosis and treatment of CAD. Fibroblasts constitute 60-70% of cardiac cells and have a crucial role in cardiovascular function. Hence, the aim of this study was to show a potential therapeutic application of proteins derived from heat-stressed fibroblast in CAD patients. Fibroblasts were isolated from the foreskin and cultured under heat stress conditions. Surprisingly, 1.06% of the cells exhibited a necrotic death pattern. Furthermore, heat-stressed fibroblasts produced higher level of total proteins than control cells. In SDS-PAGE analysis, a 70 kDa protein band was observed in stressed cell culture supernatants which appeared as two acidic spots with close pI in the two-dimensional electrophoresis. To evaluate the immunogenic properties of fibroblast-derived heat shock proteins (HSPs), the serum immunoglobulin-G (IgG) was measured by ELISA in 50 CAD patients and 50 normal subjects who had been diagnosed through angiography. Interestingly, the level of anti-HSP antibody was significantly higher in non-CAD individuals in comparison with the patient's group (p < 0.05). The odds ratio for CAD was 5.06 (95%CI = 2.15-11.91) in cut-off value of 30 AU/mL of anti-HSP antibody. Moreover, ROC analysis showed that anti-HSP antibodies had a specificity of 74% and a sensitivity of 64%, which is almost equal to 66% sensitivity of exercise stress test (EST) as a CAD diagnostic method. These data revealed that fibroblast-derived HSPs are suitable for the diagnosis and management of CAD through antibody production.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Fibroblastos/imunologia , Resposta ao Choque Térmico/imunologia , Idoso , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/fisiologia , Proteínas de Choque Térmico/biossíntese , Proteínas de Choque Térmico/imunologia , Resposta ao Choque Térmico/fisiologia , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Razão de Chances
6.
Int J Nanomedicine ; 16: 4739-4753, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267520

RESUMO

Background: Serological tests detecting severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are widely used in seroprevalence studies and evaluating the efficacy of the vaccination program. Some of the widely used serological testing techniques are enzyme-linked immune-sorbent assay (ELISA), chemiluminescence immunoassay (CLIA), and lateral flow immunoassay (LFIA). However, these tests are plagued with low sensitivity or specificity, time-consuming, labor-intensive, and expensive. We developed a serological test implementing flow-through dot-blot assay (FT-DBA) for SARS-CoV-2 specific IgG detection, which provides enhanced sensitivity and specificity while being quick to perform and easy to use. Methods: SARS-CoV-2 antigens were immobilized on nitrocellulose membrane to capture human IgG, which was then detected with anti-human IgG conjugated gold nanoparticle (hIgG-AuNP). A total of 181 samples were analyzed in-house. Within which 35 were further evaluated in US FDA-approved CLIA Elecsys SARS-CoV-2 assay. The positive panel consisted of RT-qPCR positive samples from patients with both <14 days and >14 days from the onset of clinical symptoms. The negative panel contained samples collected from the pre-pandemic era dengue patients and healthy donors during the pandemic. Moreover, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FT-DBA were evaluated against RT-qPCR positive sera. However, the overall efficacies were assessed with sera that seroconverted against either nucleocapsid (NCP) or receptor-binding domain (RBD). Results: In-house ELISA selected a total of 81 true seropositive and 100 seronegative samples. The sensitivity of samples with <14 days using FT-DBA was 94.7%, increasing to 100% for samples >14 days. The overall detection sensitivity and specificity were 98.8% and 98%, respectively, whereas the overall PPV and NPV were 99.6% and 99%. Moreover, comparative analysis between in-house ELISA assays and FT-DBA revealed clinical agreement of Cohen's Kappa value of 0.944. The FT-DBA showed sensitivity and specificity of 100% when compared with commercial CLIA kits. Conclusion: The assay can confirm past SARS-CoV-2 infection with high accuracy within 2 minutes compared to commercial CLIA or in-house ELISA. It can help track SARS-CoV-2 disease progression, population screening, and vaccination response. The ease of use of the assay without requiring any instruments while being semi-quantitative provides the avenue of its implementation in remote areas around the globe, where conventional serodiagnosis is not feasible.


Assuntos
Ouro/química , Immunoblotting/métodos , Imunoglobulina G/análise , Nanopartículas Metálicas/química , Nucleocapsídeo/análise , SARS-CoV-2/isolamento & purificação , Adulto , Anticorpos Antivirais/sangue , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Valor Preditivo dos Testes , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
7.
Front Immunol ; 12: 680188, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262564

RESUMO

A significant proportion of COVID-19 patients will progress to critical illness requiring invasive mechanical ventilation. This accentuates the need for a therapy that can reduce the severity of COVID-19. Clinical trials have shown the effectiveness of remdesivir in shortening recovery time and decreasing progression to respiratory failure and mechanical ventilation. However, some studies have highlighted its lack of efficacy in patients on high-flow oxygen and mechanical ventilation. This study uncovers some underlying immune response differences between responders and non-responders to remdesivir treatment. Immunological analyses revealed an upregulation of tissue repair factors BDNF, PDGF-BB and PIGF-1, as well as an increase in ratio of Th2-associated cytokine IL-4 to Th1-associated cytokine IFN-γ. Serological profiling of IgG subclasses corroborated this observation, with significantly higher magnitude of increase in Th2-associated IgG2 and IgG4 responses. These findings help to identify the mechanisms of immune regulation accompanying successful remdesivir treatment in severe COVID-19 patients.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , Citocinas/sangue , Hospitalização , SARS-CoV-2/genética , Monofosfato de Adenosina/uso terapêutico , Adulto , Idoso , Alanina/uso terapêutico , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Becaplermina/sangue , Fator Neurotrófico Derivado do Encéfalo/sangue , COVID-19/sangue , COVID-19/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Proteínas de Membrana/sangue , Pessoa de Meia-Idade , Estudos Prospectivos , Glicoproteína da Espícula de Coronavírus/imunologia , Resultado do Tratamento
8.
Front Immunol ; 12: 690698, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276681

RESUMO

Patients with kidney failure have notoriously weak responses to common vaccines. Thus, immunogenicity of novel SARS-CoV-2 vaccines might be impaired in this group. To determine immunogenicity of SARS-CoV-2 vaccination in patients with chronic dialysis, we analyzed the humoral and T-cell response after two doses of mRNA vaccine Tozinameran (BNT162b2 BioNTech/Pfizer). This observational study included 43 patients on dialysis before vaccination with two doses of Tozinameran 21 days apart. Overall, 36 patients completed the observation period until three weeks after the second dose and 32 patients were further analyzed at week 10. Serum samples were analyzed by SARS-CoV-2 specific IgG and IgA antibodies ~1, ~3-4 and ~10 weeks after the second vaccination. In addition, SARS-CoV-2-specific T-cell responses were assessed at ~3-4 weeks by an interferon-gamma release assay (IGRA). Antibody and T cell outcomes at this timepoint were compared to a group of 44 elderly patients not on dialysis, after immunization with Tozinameran. Median age of patients on chronic dialysis was 74.0 years (IQR 66.0, 82.0). The proportion of males was higher (69.4%) than females. Only 20/36 patients (55.6%, 95%CI: 38.29-71.67) developed SARS-CoV-2-IgG antibodies at the first sampling, whereas 32/36 patients (88.9%, 95%CI: 73.00-96.38) demonstrated IgG detection at the second sampling. In a longitudinal follow-up at ~10 weeks after the second dose, the proportion of dialysis patients reactive for anti-SARS-CoV-2-IgG decreased to 27/32 (84.37%, 95%CI: 66.46-94.10) The proportion of anti-SARS-CoV-2 S1 IgA decreased from 33/36 (91.67%; 95%CI: 76.41-97.82) at weeks 3-4 down to 19/32 (59.38; 95%CI: 40.79-75.78). Compared to a cohort of vaccinees with similar age but not on chronic dialysis seroconversion rates and antibody titers were significantly lower. SARS-CoV-2-specific T-cell responses 3 weeks after second vaccination were detected in 21/31 vaccinated dialysis patients (67.7%, 95%CI: 48.53-82.68) compared to 42/44 (93.3%, 95%CI: 76.49-98.84) in controls of similar age. Patients on dialysis demonstrate a delayed, but robust immune response three to four weeks after the second dose, which indicates effective vaccination of this vulnerable group. However, the lower immunogenicity of Tozinameran in these patients needs further attention to develop potential countermeasures such as an additional booster vaccination.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Imunogenicidade da Vacina , Diálise Renal , SARS-CoV-2/imunologia , Vacinação/métodos , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/sangue , COVID-19/virologia , Feminino , Seguimentos , Humanos , Imunidade , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia
9.
Viruses ; 13(7)2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202849

RESUMO

The progression and distribution of the SARS-CoV-2 pandemic are continuously changing over time and can be traced by blood donors' serological survey. Here, we investigated the seroprevalence of anti-SARS-CoV-2 antibodies in blood donors in Nuevo Leon, Mexico during 2020 as a strategy for the rapid evaluation of the spread of SARS-CoV-2 and asymptomatic case detection. We collected residual plasma samples from blood donors who attended two regional donation centers from January to December of 2020 to identify changes in anti-SARS-CoV-2 IgG prevalence. Plasma samples were analyzed on the Abbott Architect instrument using the commercial Abbott SARS-CoV-2 IgG chemiluminescent assay. We found a total of 99 reactive samples from 2068 analyzed plasma samples, resulting in a raw prevalence of 4.87%. Donors aged 18-49 years were more likely to be seropositive compared to those aged >50 years (p < 0.001). Weekly seroprevalence increased from 1.8% during the early pandemic stage to 27.59% by the end of the year. Prevalence was 1.46-fold higher in females compared to males. Case geographical mapping showed that Monterrey city recorded the majority of SARS-CoV-2 cases. These results show that there is a growing trend of seroprevalence over time associated with asymptomatic infection that is unnoticed under the current epidemiological surveillance protocols.


Assuntos
Anticorpos Antivirais/sangue , Infecções Assintomáticas/epidemiologia , Doadores de Sangue , COVID-19/epidemiologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Fatores Etários , Idoso , Doadores de Sangue/estatística & dados numéricos , COVID-19/transmissão , Estudos Transversais , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Soroepidemiológicos , Fatores Sexuais , Adulto Jovem
10.
Viruses ; 13(7)2021 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206895

RESUMO

The number of serological assays for SARS-CoV-2 has skyrocketed in the past year. Concerns have been raised regarding their performance characteristics, depending on the disease severity and the time of the analysis post-symptom onset (PSO). Thus, independent validations using an unbiased sample selection are required for meaningful serology data interpretation. We aimed to assess the clinical performance of six commercially available assays, the seroconversion, and the dynamics of the humoral response to SARS-CoV-2 infection. The study included 528 serum samples from 156 patients with follow-up visits up to six months PSO and 161 serum samples from healthy people. The IgG/total antibodies positive percentage increased and remained above 95% after six months when chemiluminescent immunoassay (CLIA) IgG antiS1/S2 and electro-chemiluminescent assay (ECLIA) total antiNP were used. At early time points PSO, chemiluminescent microparticle immunoassay (CMIA) IgM antiS achieved the best sensitivity. IgM and IgG appear simultaneously in most circumstances, and when performed in parallel the sensitivity increases. The severe and the moderate clinical forms were significantly associated with higher seropositivity percentage and antibody levels. High specificity was found in all evaluated assays, but the sensitivity was variable depending on the time PSO, severity of disease, detection method and targeted antigen.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , Teste Sorológico para COVID-19/normas , COVID-19/diagnóstico , COVID-19/imunologia , Kit de Reagentes para Diagnóstico/normas , SARS-CoV-2/imunologia , Adulto , COVID-19/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Estudos Longitudinais , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Romênia , Sensibilidade e Especificidade , Fatores de Tempo
11.
BMC Infect Dis ; 21(1): 704, 2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34303348

RESUMO

BACKGROUND: The co-circulation of types of arbovirus in areas where they are endemic increased the risk of outbreaks and limited the diagnostic methods available. Here, we analyze the epidemiological profile of DENV, CHIKV and ZIKV at the serological and molecular level in patients with suspected infection with these arboviruses in the city of Juazeiro do Norte, Ceará, Brazil. METHODS: In 2016, the Central Public Health Laboratory (LACEN) of Juazeiro do Norte received 182 plasma samples from patients who visited health facilities with symptoms compatible with arbovirus infection. The LACEN performed serological tests for detection of IgM/IgG to DENV and CHIKV. They then sent these samples to the Retrovirology Laboratory of the Federal University of São Paulo and Faculty of Medical of the ABC where molecular analyses to confirm the infection by DENV, ZIKV and CHIKV were performed. The prevalence of IgM/IgG antibodies and of infections confirmed by RT-qPCR were presented with 95% confidence interval. RESULTS: In serologic analysis, 125 samples were positive for antibodies against CHIKV and all were positive for antibodies against DENV. A higher prevalence of IgG against CHIKV (63.20% with 95% CI: 45.76-70.56) than against DENV (95.05% with 95% CI: 78.09-98.12) was observed. When the samples were submitted to analysis by RT-qPCR, we observed the following prevalence: mono-infection by ZIKV of 19.23% (95% CI: 14.29-34.82) patients, mono-infection by CHIKV of 3.84% (95% CI: 2.01-5.44) and co-infection with ZIKV and CHIKV of 1.09% (95% CI: 0.89-4.56). CONCLUSION: The serologic and molecular tests performed in this study were effective in analyzing the epidemiological profile of DENV, CHIKV and ZIKV in patients with suspected infection by these arboviruses in the city of Juazeiro do Norte, Ceará/Brazil.


Assuntos
Anticorpos Antivirais/sangue , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/imunologia , Vírus da Dengue/imunologia , Dengue/epidemiologia , Infecção por Zika virus/epidemiologia , Zika virus/imunologia , Adulto , Brasil/epidemiologia , Febre de Chikungunya/terapia , Cidades/epidemiologia , Estudos Transversais , Dengue/terapia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Reação em Cadeia da Polimerase em Tempo Real , Medição de Risco , Testes Sorológicos , Infecção por Zika virus/terapia
12.
PLoS One ; 16(7): e0254667, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34260645

RESUMO

The world is currently in a pandemic of COVID-19 (Coronavirus disease-2019) caused by a novel positive-sense, single-stranded RNA ß-coronavirus referred to as SARS-CoV-2. Here we investigated rates of SARS-CoV-2 infection in the greater Cincinnati, Ohio, USA metropolitan area from August 13 to December 8, 2020, just prior to initiation of the national vaccination program. Examination of 9,550 adult blood donor volunteers for serum IgG antibody positivity against the SARS-CoV-2 Spike protein showed an overall prevalence of 8.40%, measured as 7.56% in the first 58 days and 9.24% in the last 58 days, and 12.86% in December 2020, which we extrapolated to ~20% as of March, 2021. Males and females showed similar rates of past infection, and rates among Hispanic or Latinos, African Americans and Whites were also investigated. Donors under 30 years of age had the highest rates of past infection, while those over 60 had the lowest. Geographic analysis showed higher rates of infectivity on the West side of Cincinnati compared with the East side (split by I-75) and the lowest rates in the adjoining region of Kentucky (across the Ohio river). These results in regional seroprevalence will help inform efforts to best achieve herd immunity in conjunction with the national vaccination campaign.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue/estatística & dados numéricos , COVID-19/epidemiologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Ohio/etnologia , Pandemias , Estudos Soroepidemiológicos , Adulto Jovem
13.
JAMA Netw Open ; 4(7): e2116543, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34287634

RESUMO

Importance: Detailed analysis of infection rates paired with behavioral and employee-reported risk factors is vital to understanding how transmission of SARS-CoV-2 infection may be exacerbated or mitigated in the workplace. Institutions of higher education are heterogeneous work units that supported continued in-person employment during the COVID-19 pandemic, providing a test site for occupational health evaluation. Objective: To evaluate the association between self-reported protective behaviors and prevalence of SARS-CoV-2 infection among essential in-person employees during the first 6 months of the COVID-19 pandemic in the US. Design, Setting, and Participants: This cross-sectional study was conducted from July 13 to September 2, 2020, at an institution of higher education in Fort Collins, Colorado. Employees 18 years or older without symptoms of COVID-19 who identified as essential in-person workers during the first 6 months of the pandemic were included. Participants completed a survey, and blood and nasal swab samples were collected to assess active SARS-CoV-2 infection via quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and past infection by serologic testing. Exposure: Self-reported practice of protective behaviors against COVID-19 according to public health guidelines provided to employees. Main Outcomes and Measures: Prevalence of current SARS-CoV-2 infection detected by qRT-PCR or previous SARS-CoV-2 infection detected by an IgG SARS-CoV-2 testing platform. The frequency of protective behavior practices and essential workers' concerns regarding contracting COVID-19 and exposing others were measured based on survey responses. Results: Among 508 participants (305 [60.0%] women, 451 [88.8%] non-Hispanic White individuals; mean [SD] age, 41.1 [12.5] years), there were no qRT-PCR positive test results, and only 2 participants (0.4%) had seroreactive IgG antibodies. Handwashing and mask wearing were reported frequently both at work (480 [94.7%] and 496 [97.8%] participants, respectively) and outside work (465 [91.5%] and 481 [94.7%] participants, respectively). Social distancing was reported less frequently at work (403 [79.5%]) than outside work (465 [91.5%]) (P < .001). Participants were more highly motivated to avoid exposures because of concern about spreading the infection to others (419 [83.0%]) than for personal protection (319 [63.2%]) (P < .001). Conclusions and Relevance: In this cross-sectional study of essential workers at an institution of higher education, when employees reported compliance with public health practices both at and outside work, they were able to operate safely in their work environment during the COVID-19 pandemic.


Assuntos
COVID-19 , Pandemias , Saúde Pública , SARS-CoV-2 , Comportamento Social , Universidades , Local de Trabalho , Adulto , COVID-19/sangue , COVID-19/prevenção & controle , COVID-19/transmissão , COVID-19/virologia , Teste para COVID-19 , Colorado , Controle de Doenças Transmissíveis , Estudos Transversais , Feminino , Guias como Assunto , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Saúde do Trabalhador , Reação em Cadeia da Polimerase , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/imunologia , Autorrelato
14.
Viruses ; 13(7)2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208954

RESUMO

There are some reports and case series addressing Coronavirus Disease 2019 (COVID-19) infections during pregnancy in upper income countries, but there are few data on pregnant women with comorbid conditions in low and middle income Countries. This study evaluated the proportion and the maternal and neonatal outcomes associated with SARS-CoV-2 infection among pregnant women with comorbidities. Participants were recruited consecutively in order of admission to a maternity for pregnant women with comorbidities. Sociodemographic, clinical, and laboratory data were prospectively collected during hospitalization. Pregnant women were screened at entry: nasopharyngeal swabs were tested by RT-PCR; serum samples were tested for IgG antibodies against spike protein by ELISA. From April to June 2020, 115 eligible women were included in the study. The proportion of SARS-CoV-2 infection was 28.7%. The rate of obesity was 60.9%, vascular hypertension 40.0%, and HIV 21.7%. The most common clinical presentations were ageusia (21.2%), anosmia (18.2%), and fever (18.2%). Prematurity was higher among mothers who had a SARS-CoV-2 infection based on RT-PCR. There were two cases of fetal demise. We found a high proportion of COVID-19 among pregnant women with comorbidities. This underscores the importance of antenatal care during the pandemic to implement universal SARS-CoV-2 screening, precautionary measures, and the rollout of vaccination programs for pregnant women.


Assuntos
COVID-19/epidemiologia , Imunoglobulina G/sangue , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/virologia , SARS-CoV-2/imunologia , Adulto , COVID-19/imunologia , Estudos de Coortes , Comorbidade , Feminino , Hospitalização , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Obesidade/complicações , Obesidade/virologia , Projetos Piloto , Gravidez , Gestantes , SARS-CoV-2/genética , Adulto Jovem
15.
Mikrochim Acta ; 188(8): 261, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34278534

RESUMO

The ongoing global pandemic of SARS-CoV-2 has promoted to develop novel serological testing technologies since they can be effectively complementary to RT-PCR. Here, a new all-fiber Fresnel reflection microfluidic biosensor (FRMB) was constructed through combining all-fiber optical system, microfluidic chip, and multimode fiber bio-probe. The transmission of the incident light and the collection and transmission of Fresnel reflection light are achieved using a single-multi-mode fiber optic coupler (SMFC) without any other optical separation elements. This compact design greatly simplifies the whole system structure and improves light transmission efficiency, which makes it suitable for the label-free, sensitive, and easy-to-use point-of-care testing (POCT) of targets in nanoliter samples. Based on Fresnel reflection mechanism and immunoassay principle, both the SARS-CoV-2 IgM and IgG antibodies against the SARS-CoV-2 spike protein could be sensitively quantified in 7 min using the secondary antibodies-modified multimode fiber bio-probe. The FRMB performs in one-step, is accurate, label-free, and sensitive in situ/on-site detection of SARS-CoV-2 IgM or IgG in serum with simple dilution only. The limits of detection of SARS-CoV-2 IgM and SARS-CoV-2 IgG were 0.82 ng/mL and 0.45 ng/mL, respectively. Based on our proposed theory, the affinity constants of SARS-CoV-2 IgM or IgG antibody and their respective secondary antibodies were also determined. The FRMB can be readily extended as a universal platform for the label-free, rapid, and sensitive in situ/on-site measurement of other biomarkers and the investigation of biomolecular interaction.


Assuntos
Anticorpos Antivirais/sangue , Técnicas Biossensoriais/métodos , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Técnicas Analíticas Microfluídicas/métodos , SARS-CoV-2/imunologia , Anticorpos Antivirais/imunologia , Humanos , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Limite de Detecção , SARS-CoV-2/química , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia
16.
Nat Commun ; 12(1): 4383, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34282139

RESUMO

In February and March 2020, two mass swab testing campaigns were conducted in Vo', Italy. In May 2020, we tested 86% of the Vo' population with three immuno-assays detecting antibodies against the spike and nucleocapsid antigens, a neutralisation assay and Polymerase Chain Reaction (PCR). Subjects testing positive to PCR in February/March or a serological assay in May were tested again in November. Here we report on the results of the analysis of the May and November surveys. We estimate a seroprevalence of 3.5% (95% Credible Interval (CrI): 2.8-4.3%) in May. In November, 98.8% (95% Confidence Interval (CI): 93.7-100.0%) of sera which tested positive in May still reacted against at least one antigen; 18.6% (95% CI: 11.0-28.5%) showed an increase of antibody or neutralisation reactivity from May. Analysis of the serostatus of the members of 1,118 households indicates a 26.0% (95% CrI: 17.2-36.9%) Susceptible-Infectious Transmission Probability. Contact tracing had limited impact on epidemic suppression.


Assuntos
Anticorpos Antivirais/imunologia , Teste para COVID-19/métodos , COVID-19/imunologia , COVID-19/transmissão , SARS-CoV-2/imunologia , Testes Sorológicos/métodos , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste de Ácido Nucleico para COVID-19 , Busca de Comunicante , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Itália/epidemiologia , Masculino , Nucleocapsídeo , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia
17.
PLoS One ; 16(7): e0254367, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34242356

RESUMO

COVID-19 serological test must have high sensitivity as well as specificity to rule out cross-reactivity with common coronaviruses (HCoVs). We have developed a quantitative multiplex test, measuring antibodies against spike (S) proteins of SARS-CoV-2, SARS-CoV, MERS-CoV, and common human coronavirus strains (229E, NL63, OC43, HKU1), and nucleocapsid (N) protein of SARS-CoV viruses. Receptor binding domain of S protein of SARS-CoV-2 (S-RBD), and N protein, demonstrated sensitivity (94% and 92.5%, respectively) in COVID-19 patients (n = 53), with 98% specificity in non-COVID-19 respiratory-disease (n = 98), and healthy-controls (n = 129). Anti S-RBD and N antibodies appeared five to ten days post-onset of symptoms, peaking at approximately four weeks. The appearance of IgG and IgM coincided while IgG subtypes, IgG1 and IgG3 appeared soon after the total IgG; IgG2 and IgG4 remained undetectable. Several inflammatory cytokines/chemokines were found to be elevated in many COVID-19 patients (e.g., Eotaxin, Gro-α, CXCL-10 (IP-10), RANTES (CCL5), IL-2Rα, MCP-1, and SCGF-b); CXCL-10 was elevated in all. In contrast to antibody titers, levels of CXCL-10 decreased with the improvement in patient health suggesting it as a candidate for disease resolution. Importantly, anti-N antibodies appear before S-RBD and differentiate between vaccinated and infected people-current vaccines (and several in the pipeline) are S protein-based.


Assuntos
Anticorpos Antivirais , COVID-19 , Quimiocinas , Proteínas do Nucleocapsídeo de Coronavírus , Imunoglobulina G , Imunoglobulina M , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Adulto , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/imunologia , Quimiocinas/sangue , Quimiocinas/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/sangue , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Macaca mulatta , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/sangue , Fosfoproteínas/imunologia , Coelhos , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/sangue , Glicoproteína da Espícula de Coronavírus/imunologia
18.
Viruses ; 13(6)2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205134

RESUMO

This observational study evaluated SARS-CoV-2 IgG seroprevalence and related clinical, demographic, and occupational factors among workers at the largest tertiary care University-Hospital of Northwestern Italy and the University of Turin after the first pandemic wave of March-April 2020. Overall, about 10,000 individuals were tested; seropositive subjects were retested after 5 months to evaluate antibodies waning. Among 8769 hospital workers, seroprevalence was 7.6%, without significant differences related to job profile; among 1185 University workers, 3.3%. Self-reporting of COVID-19 suspected symptoms was significantly associated with positivity (Odds Ratio (OR) 2.07, 95%CI: 1.76-2.44), although 27% of seropositive subjects reported no previous symptom. At multivariable analysis, contacts at work resulted in an increased risk of 69%, or 24% for working in a COVID ward; contacts in the household evidenced the highest risk, up to more than five-fold (OR 5.31, 95%CI: 4.12-6.85). Compared to never smokers, being active smokers was inversely associated with seroprevalence (OR 0.60, 95%CI: 0.48-0.76). After 5 months, 85% of previously positive subjects still tested positive. The frequency of SARS-COV-2 infection among Health Care Workers was comparable with that observed in surveys performed in Northern Italy and Europe after the first pandemic wave. This study confirms that infection frequently occurred as asymptomatic and underlines the importance of household exposure, seroprevalence (OR 0.60, 95%CI: 0.48-0.76).


Assuntos
Anticorpos Antivirais/sangue , COVID-19/epidemiologia , COVID-19/imunologia , Pessoal de Saúde/estatística & dados numéricos , Imunoglobulina G/sangue , Centros de Atenção Terciária/estatística & dados numéricos , Adulto , Idoso , Estudos Transversais , Monitoramento Epidemiológico , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Estudos Soroepidemiológicos , Inquéritos e Questionários
19.
Sci Rep ; 11(1): 13780, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215811

RESUMO

Most patients infected with SARS-CoV-2 are asymptomatic or mildly symptomatic. However, the early and late antibody kinetics, and the association between antibody levels, clinical symptoms, and disease phase in these patients have not yet been fully defined. Confirmed SARS-CoV-2 patients and their household contacts were evaluated over a period four months. The evaluation procedure included symptom monitoring, viral load and serology analysis every ten days. A total of 1334 serum samples were collected from 135 patients and analyzed using three assays for IgG-N, IgG-S and IgM antibodies. Of the study participants, 97% were seropositive during the study, and two distinct clusters were identified. These clusters were significantly different in their inflammatory related symptoms. Peak IgG-S was 40.0 AU/ml for the non-inflammatory cluster and 71.5 AU/ml for the inflammatory cluster (P = 0.006), whereas IgG-N peaks were 4.3 and 5.87 (P = 0.023) respectively. Finally, a decision tree model was designed to predict the disease phase based on the serological titer levels, and had an overall accuracy of 80.7%. The specific profile of seroconversion and decay of serum antibodies can be used to predict the time-course from the acute infection.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Anticorpos Antivirais/sangue , COVID-19/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Carga Viral
20.
Viruses ; 13(6)2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198719

RESUMO

Humoral immunity has emerged as a vital immune component against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Nevertheless, a subset of recovered Coronavirus Disease-2019 (COVID-19) paucisymptomatic/asymptomatic individuals do not generate an antibody response, constituting a paradox. We assumed that immunodiagnostic assays may operate under a competitive format within the context of antigenemia, potentially explaining this phenomenon. We present a case where persistent antigenemia/viremia was documented for at least 73 days post-symptom onset using 'in-house' methodology, and as it progressively declined, seroconversion took place late, around day 55, supporting our hypothesis. Thus, prolonged SARS-CoV-2 antigenemia/viremia could mask humoral responses, rendering, in certain cases, the phenomenon of 'non-responders' a misnomer.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Antígenos Virais/imunologia , Teste Sorológico para COVID-19/normas , COVID-19/diagnóstico , SARS-CoV-2/imunologia , Anticorpos Antivirais/metabolismo , Antígenos Virais/metabolismo , Sítios de Ligação de Anticorpos , COVID-19/sangue , COVID-19/imunologia , COVID-19/virologia , Teste Sorológico para COVID-19/estatística & dados numéricos , Humanos , Imunidade Humoral/imunologia , Imunoglobulina G/sangue , Masculino , Sensibilidade e Especificidade , Soroconversão , Adulto Jovem
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