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1.
PLoS Med ; 17(10): e1003358, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33001967

RESUMO

BACKGROUND: Loss of smell and taste are commonly reported symptoms associated with coronavirus disease 2019 (COVID-19); however, the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in people with acute loss of smell and/or taste is unknown. The study aimed to determine the seroprevalence of SARS-CoV-2 antibodies in a community-based population with acute loss of smell and/or taste and to compare the frequency of COVID-19 associated symptoms in participants with and without SARS-CoV-2 antibodies. It also evaluated whether smell or taste loss are indicative of COVID-19 infection. METHODS AND FINDINGS: Text messages, sent via primary care centers in London, United Kingdom, invited people with loss of smell and/or taste in the preceding month, to participate. Recruitment took place between 23 April 2020 and 14 May 2020. A total of 590 participants enrolled via a web-based platform and responded to questions about loss of smell and taste and other COVID-19-related symptoms. Mean age was 39.4 years (SD ± 12.0) and 69.1% (n = 392) of participants were female. A total of 567 (96.1%) had a telemedicine consultation during which their COVID-19-related symptoms were verified and a lateral flow immunoassay test that detected SARS-CoV-2 immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies was undertaken under medical supervision. A total of 77.6% of 567 participants with acute smell and/or taste loss had SARS-CoV-2 antibodies; of these, 39.8% (n = 175) had neither cough nor fever. New loss of smell was more prevalent in participants with SARS-CoV-2 antibodies, compared with those without antibodies (93.4% versus 78.7%, p < 0.001), whereas taste loss was equally prevalent (90.2% versus 89.0%, p = 0.738). Seropositivity for SARS-CoV-2 was 3 times more likely in participants with smell loss (OR 2.86; 95% CI 1.27-6.36; p < 0.001) compared with those with taste loss. The limitations of this study are the lack of a general population control group, the self-reported nature of the smell and taste changes, and the fact our methodology does not take into account the possibility that a population subset may not seroconvert to develop SARS-CoV-2 antibodies post-COVID-19. CONCLUSIONS: Our findings suggest that recent loss of smell is a highly specific COVID-19 symptom and should be considered more generally in guiding case isolation, testing, and treatment of COVID-19. TRIALS REGISTRATION: ClinicalTrials.gov NCT04377815.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/complicações , Transtornos do Olfato/virologia , Pneumonia Viral/complicações , Distúrbios do Paladar/virologia , Adulto , Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Londres , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia , Testes Imediatos , Soroconversão , Estudos Soroepidemiológicos , Envio de Mensagens de Texto
3.
Viruses ; 12(9)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32962125

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a global health emergency. To improve the understanding of the systemic component of SARS-CoV-2, we investigated if viral load dynamics in plasma and respiratory samples are associated with antibody response and severity of coronavirus disease 2019 (COVID-19). SARS-CoV-2 RNA was found in plasma samples from 14 (44%) out of 32 patients. RNAemia was detected in 5 out of 6 fatal cases. Peak IgG values were significantly lower in mild/moderate than in severe (0.6 (interquartile range, IQR, 0.4-3.2) vs. 11.8 (IQR, 9.9-13.0), adjusted p = 0.003) or critical cases (11.29 (IQR, 8.3-12.0), adjusted p = 0.042). IgG titers were significantly associated with virus Ct (Cycle threshold) value in plasma and respiratory specimens ((ß = 0.4, 95% CI (confidence interval, 0.2; 0.5), p < 0.001 and ß = 0.5, 95% CI (0.2; 0.6), p = 0.002). A classification as severe or a critical case was additionally inversely associated with Ct values in plasma in comparison to mild/moderate cases (ß = -3.3, 95% CI (-5.8; 0.8), p = 0.024 and ß = -4.4, 95% CI (-7.2; 1.6), p = 0.007, respectively). Based on the present data, our hypothesis is that the early stage of SARS-CoV-2 infection is characterized by a primary RNAemia, as a potential manifestation of a systemic infection. Additionally, the viral load in plasma seems to be associated with a worse disease outcome.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , RNA Viral/sangue , Idoso , Betacoronavirus/genética , Betacoronavirus/imunologia , Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Feminino , Alemanha/epidemiologia , Hospitalização , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/patologia , RNA Viral/análise , Sistema Respiratório/virologia , Índice de Gravidade de Doença , Carga Viral , Viremia/sangue , Viremia/patologia , Viremia/virologia
4.
PLoS One ; 15(9): e0237694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941461

RESUMO

BACKGROUND: The SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2) is responsible for the infectious respiratory disease called COVID-19 (COronaVIrus Disease 2019). In response to the growing COVID-19 pandemic, point-of-care (POC) tests have been developed to detect specific antibodies, IgG and IgM, to SARS-CoV-2 virus in human whole blood. We conducted a prospective observational study to evaluate the performance of two POC tests, COVID-PRESTO® and COVID-DUO®, compared to the gold standard, RT-PCR (real-time reverse transcriptase polymerase chain reaction). METHODS: RT-PCR testing of SARS-Cov-2 was performed from nasopharyngeal swab specimens collected in adult patients visiting the infectious disease department at the hospital (Orléans, France). Capillary whole blood (CWB) samples from the fingertip taken at different time points after onset of the disease were tested with POC tests. The specificity and sensitivity of the rapid test kits compared to test of reference (RT-PCR) were calculated. RESULTS: Among 381 patients with symptoms of COVID-19 who went to the hospital for a diagnostic, 143 patients were RT-PCR negative. Results of test with POC tests were all negative for these patients, indicating a specificity of 100% for both POC tests. In the RT-PCR positive subgroup (n = 238), 133 patients were tested with COVID-PRESTO® and 129 patients were tested with COVID-DUO® (24 patients tested with both). The further the onset of symptoms was from the date of collection, the greater the sensitivity. The sensitivity of COVID-PRESTO® test ranged from 10.00% for patients having experienced their 1st symptoms from 0 to 5 days ago to 100% in patients where symptoms had occurred more than 15 days before the date of tests. For COVID-DUO® test, the sensitivity ranged from 35.71% [0-5 days] to 100% (> 15 days). CONCLUSION: COVID-PRESTO® and DUO® POC tests turned out to be very specific (none false positive) and to be sensitive enough after 15 days from onset of symptom. These easy to use IgG/IgM combined test kits are the first ones allowing a screening with CWB sample, by typing from a finger prick. These rapid tests are particularly interesting for screening in low resource settings.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pneumonia Viral/diagnóstico , Kit de Reagentes para Diagnóstico , Adulto , Idoso , Especificidade de Anticorpos , Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Capilares , Infecções por Coronavirus/sangue , Dedos/irrigação sanguínea , Humanos , Pessoa de Meia-Idade , Nasofaringe/virologia , Pandemias , Pneumonia Viral/sangue , Testes Imediatos , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Adulto Jovem
5.
Indian J Med Res ; 152(1 & 2): 48-60, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32952144

RESUMO

Background & objectives: Population-based seroepidemiological studies measure the extent of SARS-CoV-2 infection in a country. We report the findings of the first round of a national serosurvey, conducted to estimate the seroprevalence of SARS-CoV-2 infection among adult population of India. Methods: From May 11 to June 4, 2020, a randomly sampled, community-based survey was conducted in 700 villages/wards, selected from the 70 districts of the 21 States of India, categorized into four strata based on the incidence of reported COVID-19 cases. Four hundred adults per district were enrolled from 10 clusters with one adult per household. Serum samples were tested for IgG antibodies using COVID Kavach ELISA kit. All positive serum samples were re-tested using Euroimmun SARS-CoV-2 ELISA. Adjusting for survey design and serial test performance, weighted seroprevalence, number of infections, infection to case ratio (ICR) and infection fatality ratio (IFR) were calculated. Logistic regression was used to determine the factors associated with IgG positivity. Results: Total of 30,283 households were visited and 28,000 individuals were enrolled. Population-weighted seroprevalence after adjusting for test performance was 0.73 per cent [95% confidence interval (CI): 0.34-1.13]. Males, living in urban slums and occupation with high risk of exposure to potentially infected persons were associated with seropositivity. A cumulative 6,468,388 adult infections (95% CI: 3,829,029-11,199,423) were estimated in India by the early May. The overall ICR was between 81.6 (95% CI: 48.3-141.4) and 130.1 (95% CI: 77.0-225.2) with May 11 and May 3, 2020 as plausible reference points for reported cases. The IFR in the surveyed districts from high stratum, where death reporting was more robust, was 11.72 (95% CI: 7.21-19.19) to 15.04 (9.26-24.62) per 10,000 adults, using May 24 and June 1, 2020 as plausible reference points for reported deaths. Interpretation & conclusions: Seroprevalence of SARS-CoV-2 was low among the adult population in India around the beginning of May 2020. Further national and local serosurveys are recommended to better inform the public health strategy for containment and mitigation of the epidemic in various parts of the country.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/genética , Infecções por Coronavirus/epidemiologia , Imunoglobulina G/sangue , Pneumonia Viral/epidemiologia , Adolescente , Adulto , Idoso , Betacoronavirus/patogenicidade , Infecções por Coronavirus/sangue , Infecções por Coronavirus/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/virologia , Estudos Soroepidemiológicos , Adulto Jovem
7.
Infez Med ; 28(3): 357-366, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920571

RESUMO

The current COVID-19 pandemic needs unconventional therapies to tackle the resulted high morbidity and mortality. Convalescent plasma is one of the therapeutic approaches that might be of benefit. Forty nine early-stage critically-ill COVID-19 patients residing in Respiratory Care Units (RCU) of three hospitals in Baghdad, Iraq, were included: 21 received convalescent plasma while 28, namely control group, did not receive it. Recovery or death, length of stay in hospital, and improvement in the clinical course of the disease were monitored clinically along with laboratory monitoring through SARS-CoV-2 RNA detection via PCR, and SARS-CoV-2 IgG and IgM serological monitoring. Patients who received convalescent plasma showed reduced duration of infection in about 4 days and showed less death rate [1/21 versus 8/28 in control group]. In addition, all the patients who were given convalescent plasma showed high levels of SARS-CoV-2 IgG and IgM three days after plasma transfusion. Plasma from donors with high levels of SARS-CoV-2 IgG and donors with positive SRAS-CoV-2 IgM showed better therapeutic results than other donors. Convalescent plasma therapy is an effective therapy if donors with high level of SARS-Cov2 antibodies are selected and if recipients are at their early stage of critical illness, being no more than three days in RCUs.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/terapia , Plasma/imunologia , Pneumonia Viral/terapia , Anticorpos Antivirais/sangue , Estudos de Casos e Controles , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Estado Terminal/terapia , Feminino , Humanos , Imunização Passiva/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Iraque/epidemiologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia
8.
BMC Infect Dis ; 20(1): 698, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32962655

RESUMO

BACKGROUND: A new coronavirus disease 2019 (COVID-19) has escalated to a pandemic since its first outbreak in Wuhan, China. A small proportion of patients may have difficulty in generating IgM or IgG antibodies against SARS-CoV-2, and little attention has been paid to them. CASE PRESENTATIONS: We present two cases of confirmed COVID-19 patients and characterize their initial symptoms, chest CT results, medication, and laboratory test results in detail (including RT-PCR, IgM/ IgG, cytokine and blood cell counts). CONCLUSION: Both of patients with confirmed COVID-19 pneumonia failed to produce either IgM or IgG even 40 to 50 days after their symptoms onset. This work provides evidence demonstrating that at least a small proportion of patients may have difficulty in rapidly gaining immunity against SARS-CoV-2.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/diagnóstico , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pneumonia Viral/diagnóstico , Adulto , Betacoronavirus , China/epidemiologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia
9.
J Clin Virol ; 131: 104609, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32866811

RESUMO

INTRODUCTION: IgG immunoassays have been developed and used widely for clinical samples and serosurveys for SARS-CoV2, with most detecting antibodies against the spike/receptor-binding-domain or nucleocapsid. Limited information is available on comparative evaluation of IgG immunoassays against a clinical reference standard, i.e., RT-PCR positivity with >20 days of illness. This study addresses the need for comparing clinical performance of IgG immunoassays with respect to this alternate reference standard. METHODS: We compared the performance of three immunoassays, an in-house RBD assay, and two commercial assays, the Diasorin LIAISON SARS-CoV-2 S1/S1 IgG CLIA which detects antibodies against S1/S2 domains of the Spike protein and the Zydus Kavach assay based on inactivated virus using a well-characterized panel of sera. 379 sera and plasma samples from RTPCR positive individuals >20 days of illness in symptomatic or RT-PCR positivity in asymptomatic individuals and 184 samples collected prior to 2019 were used for assay evaluation. RESULTS: The sensitivity of the assays were 84.7 (95 %CI 80.6-88.1), 82.6 (95 %CI 78.3-86.2) and 75.7 (95 %CI 71.0-79.9) respectively for RBD, LIAISON and Kavach. Kavach and the in-house RBD ELISA showed a specificity of 99.5 % and 100 %, respectively. The RBD and LIAISON (S1/S2) assays showed high agreement (94.7 %; 95 %CI: 92.0, 96.6) and were able to correctly identify more positive sera/plasma than Kavach. CONCLUSION: Independent comparisons support the evaluation of performance characteristics of immunoassays. All three assays are suitable for serosurveillance studies, but in low prevalence sites, estimation of exposure may require adjustment based on our findings.


Assuntos
Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/imunologia , Imunoensaio/métodos , Imunoglobulina G/sangue , Pneumonia Viral/imunologia , Automação Laboratorial , Betacoronavirus , Infecções por Coronavirus/diagnóstico , Humanos , Índia , Estudos Longitudinais , Medições Luminescentes , Pandemias , Estudos Prospectivos , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
10.
Lancet ; 396(10255): 887-897, 2020 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-32896291

RESUMO

BACKGROUND: We developed a heterologous COVID-19 vaccine consisting of two components, a recombinant adenovirus type 26 (rAd26) vector and a recombinant adenovirus type 5 (rAd5) vector, both carrying the gene for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein (rAd26-S and rAd5-S). We aimed to assess the safety and immunogenicity of two formulations (frozen and lyophilised) of this vaccine. METHODS: We did two open, non-randomised phase 1/2 studies at two hospitals in Russia. We enrolled healthy adult volunteers (men and women) aged 18-60 years to both studies. In phase 1 of each study, we administered intramuscularly on day 0 either one dose of rAd26-S or one dose of rAd5-S and assessed the safety of the two components for 28 days. In phase 2 of the study, which began no earlier than 5 days after phase 1 vaccination, we administered intramuscularly a prime-boost vaccination, with rAd26-S given on day 0 and rAd5-S on day 21. Primary outcome measures were antigen-specific humoral immunity (SARS-CoV-2-specific antibodies measured by ELISA on days 0, 14, 21, 28, and 42) and safety (number of participants with adverse events monitored throughout the study). Secondary outcome measures were antigen-specific cellular immunity (T-cell responses and interferon-γ concentration) and change in neutralising antibodies (detected with a SARS-CoV-2 neutralisation assay). These trials are registered with ClinicalTrials.gov, NCT04436471 and NCT04437875. FINDINGS: Between June 18 and Aug 3, 2020, we enrolled 76 participants to the two studies (38 in each study). In each study, nine volunteers received rAd26-S in phase 1, nine received rAd5-S in phase 1, and 20 received rAd26-S and rAd5-S in phase 2. Both vaccine formulations were safe and well tolerated. The most common adverse events were pain at injection site (44 [58%]), hyperthermia (38 [50%]), headache (32 [42%]), asthenia (21 [28%]), and muscle and joint pain (18 [24%]). Most adverse events were mild and no serious adverse events were detected. All participants produced antibodies to SARS-CoV-2 glycoprotein. At day 42, receptor binding domain-specific IgG titres were 14 703 with the frozen formulation and 11 143 with the lyophilised formulation, and neutralising antibodies were 49·25 with the frozen formulation and 45·95 with the lyophilised formulation, with a seroconversion rate of 100%. Cell-mediated responses were detected in all participants at day 28, with median cell proliferation of 2·5% CD4+ and 1·3% CD8+ with the frozen formulation, and a median cell proliferation of 1·3% CD4+ and 1·1% CD8+ with the lyophilised formulation. INTERPRETATION: The heterologous rAd26 and rAd5 vector-based COVID-19 vaccine has a good safety profile and induced strong humoral and cellular immune responses in participants. Further investigation is needed of the effectiveness of this vaccine for prevention of COVID-19. FUNDING: Ministry of Health of the Russian Federation.


Assuntos
Infecções por Coronavirus/prevenção & controle , Imunização Secundária , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Adenoviridae , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G/sangue , Injeções Intramusculares , Masculino , Federação Russa , Vacinas Virais/efeitos adversos , Adulto Jovem
11.
Emerg Microbes Infect ; 9(1): 2013-2019, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32867625

RESUMO

COVID-19 is a new respiratory illness caused by SARS-CoV-2, and has constituted a global public health emergency. Cat is susceptible to SARS-CoV-2. However, the prevalence of SARS-CoV-2 in cats remains largely unknown. Here, we investigated the infection of SARS-CoV-2 in cats during COVID-19 outbreak in Wuhan by serological detection methods. A cohort of serum samples were collected from cats in Wuhan, including 102 sampled after COVID-19 outbreak, and 39 prior to the outbreak. Fifteen sera collected after the outbreak were positive for the receptor binding domain (RBD) of SARS-CoV-2 by indirect enzyme linked immunosorbent assay (ELISA). Among them, 11 had SARS-CoV-2 neutralizing antibodies with a titer ranging from 1/20 to 1/1080. No serological cross-reactivity was detected between SARS-CoV-2 and type I or II feline infectious peritonitis virus (FIPV). In addition, we continuously monitored serum antibody dynamics of two positive cats every 10 days over 130 days. Their serum antibodies reached the peak at 10 days after first sampling, and declined to the limit of detection within 110 days. Our data demonstrated that SARS-CoV-2 has infected cats in Wuhan during the outbreak and described serum antibody dynamics in cats, providing an important reference for clinical treatment and prevention of COVID-19.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/veterinária , Pandemias/veterinária , Pneumonia Viral/veterinária , Animais , Gatos , China , Infecções por Coronavirus/epidemiologia , Coronavirus Felino/imunologia , Reações Cruzadas/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/sangue , Proteínas do Nucleocapsídeo/imunologia , Pneumonia Viral/epidemiologia , Glicoproteína da Espícula de Coronavírus/imunologia
12.
Elife ; 92020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894217

RESUMO

Understanding and mitigating SARS-CoV-2 transmission hinges on antibody and viral RNA data that inform exposure and shedding, but extensive variation in assays, study group demographics and laboratory protocols across published studies confounds inference of true biological patterns. Our meta-analysis leverages 3214 datapoints from 516 individuals in 21 studies to reveal that seroconversion of both IgG and IgM occurs around 12 days post-symptom onset (range 1-40), with extensive individual variation that is not significantly associated with disease severity. IgG and IgM detection probabilities increase from roughly 10% at symptom onset to 98-100% by day 22, after which IgM wanes while IgG remains reliably detectable. RNA detection probability decreases from roughly 90% to zero by day 30, and is highest in feces and lower respiratory tract samples. Our findings provide a coherent evidence base for interpreting clinical diagnostics, and for the mathematical models and serological surveys that underpin public health policies.


Assuntos
Betacoronavirus/genética , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , RNA Viral/análise , Anticorpos Antivirais/sangue , Anticorpos Antivirais/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/isolamento & purificação , Imunoglobulina M/isolamento & purificação , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , RNA Viral/isolamento & purificação
13.
PLoS Pathog ; 16(9): e1008796, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32913364

RESUMO

There is an urgent need for effective treatment and preventive vaccine to contain this devastating global pandemic, which requires a comprehensive understanding of humoral responses specific to SARS-CoV-2 during the disease progression and convalescent phase of COVID-19 patients. We continuously monitored the serum IgM and IgG responses specific to four SARS-CoV-2 related antigens, including the nucleoprotein (NP), receptor binding domain (RBD), S1 protein, and ectodomain (ECD) of the spike protein among non-severe and severe COVID-19 patients for seven weeks since disease onset. Most patients generated humoral responses against NP and spike protein-related antigens but with their distinct kinetics profiles. Combined detection of NP and ECD antigens as detecting antigen synergistically improved the sensitivity of the serological assay, compared to that of using NP or RBD as detection antigen. 80.7% of convalescent sera from COVID-19 patients revealed that the varying extents of neutralization activities against SARS-CoV-2. S1-specific and ECD-specific IgA responses were strongly correlated with the neutralization activities in non-severe patients, but not in severe patients. Moreover, the neutralizing activities of the convalescent sera were shown to significantly decline during the period between 21 days to 28 days after hospital discharge, accompanied by a substantial drop in RBD-specific IgA response. Our data provide evidence that are crucial for serological testing, antibody-based intervention, and vaccine design of COVID-19.


Assuntos
Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/patogenicidade , Humanos , Imunoglobulina G/sangue , Estudos Longitudinais , Pandemias , Testes Sorológicos , Glicoproteína da Espícula de Coronavírus/imunologia
14.
Euro Surveill ; 25(36)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32914745

RESUMO

In August 2020, during the coronavirus disease (COVID-19) pandemic, five locally acquired cases of dengue virus type 1 were detected in a family cluster in Vicenza Province, North-East Italy where Aedes albopictus mosquitoes are endemic. The primary case was an importation from West Sumatra, Indonesia. This is the first outbreak of autochthonous dengue reported in Italy. During the COVID-19 pandemic, screening of febrile travelers from endemic countries is crucial in areas where competent vectors are present.


Assuntos
Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Viagem , Adulto , Pré-Escolar , Dengue/epidemiologia , Dengue/imunologia , Dengue/virologia , Vírus da Dengue/genética , Surtos de Doenças , Transmissão de Doença Infecciosa , Feminino , Febre/etiologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Indonésia , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Artigo em Inglês | MEDLINE | ID: mdl-32906596

RESUMO

A critical point in the management of the SARS-CoV-2 pandemic is the need to promptly identify the greatest number of infected people and to implement strict public health measures. In this study, the performance of a rapid serological test in a clinical setting was evaluated. Samples from 819 consecutive patients (with or without respiratory symptoms) admitted to a large Emergency Department were tested between 23 March and 21 April 2020. Patient samples were tested in a real-time PCR assay and a serological assay. In total, 148/819 patients (18.1%) tested positive for SARS-CoV-2 by real-time PCR. The serological test revealed that 70/819 patients (8.5%) had anti-SARS-CoV-2 IgM and/or IgG. The prevalence of anti-SARS-CoV-2 antibodies was significantly higher in patients with respiratory symptoms lasting for >7 days than in those with respiratory symptoms lasting for 0-7 days (p < 0.001). The serological assay had an overall sensitivity of 35.1% and an overall specificity of 97.3%. A high negative predictive value (96.7%) was reported for patients without respiratory symptoms. The results confirm that rapid serological assays alone are not sufficient for diagnosis of SARS-CoV-2 infection but can be incorporated into large-scale screening programs during periods in which the virus circulation is low.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Serviço Hospitalar de Emergência/estatística & dados numéricos , Pandemias , Pneumonia Viral/diagnóstico , Testes Sorológicos/métodos , Infecções por Coronavirus/epidemiologia , Humanos , Imunoglobulina G/sangue , Pneumonia Viral/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
16.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(4): 423-425, 2020 Aug 24.
Artigo em Chinês | MEDLINE | ID: mdl-32935522

RESUMO

OBJECTIVE: To examine the correlation between Toxoplasma gondii infection and spontaneous abortion among pregnant women, so as to provide the evidence for the developmentofpreventivemeasuresforspontaneousabortion. METHODS: A total of 228 serum samples collected from women with spontaneous abortion for the first time from January 2018 to December 2019 were selected as the case group, while 228 serum samples collected from pregnant women with a normal delivery and without a history of abortion during the same period were selected as the control group. The serum IgG and IgM antibodies against T. gondii were detected and compared in both groups, and the correlation between T. gondii infection and spontaneous abortion was evaluated. RESULTS: There were no significant differences between the case and control groups in terms of age, education levels, occupation, residency and proportion of keeping cats (all P values > 0.05). The positive rate of anti-T. gondii IgM antibody was significantly higher in the case group than in the control group (adjusted χ2 = 4.08, P < 0.05; OR = 8.25), while no significant difference was seen between the case and control groups (χ2 = 0.42, P > 0.05). CONCLUSIONS: Acute maternal T. gondii infection may remarkably increase the chance of spontaneous abortion. Progestational health education regarding toxoplasmosis prevention and control knowledge and detection of T. gondii infection during pregnancy should be strengthened.


Assuntos
Aborto Espontâneo , Toxoplasma , Toxoplasmose , Aborto Espontâneo/sangue , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Animais , Anticorpos Antiprotozoários/sangue , Estudos de Casos e Controles , Gatos , China/epidemiologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasmose/complicações , Toxoplasmose/epidemiologia
17.
Emerg Microbes Infect ; 9(1): 1955-1957, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32869728

RESUMO

The case refers to a 51-year-old symptomatic man with a new SARS-CoV-2 RNA positive nasopharyngeal swab after two negative ones and the lack of significant development of antibody response measured by different diagnostic serological test. Our case underlines that a discrepancy between clinical course of SARS-CoV-2 infection and results from diagnostic tests may exist. This concept is rapidly emerging and supports the need for a deep knowledge of available and "in development" tests for a correct interpretation of their findings.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Imunoglobulina G/sangue , Pneumonia Viral/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Reações Falso-Negativas , Humanos , Hidroxicloroquina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/tratamento farmacológico , Reação em Cadeia da Polimerase , Quarentena , Recidiva , Testes Sorológicos , Carga Viral
18.
19.
Pediatr Infect Dis J ; 39(10): e321-e324, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32932334

RESUMO

Although first considered a benign infection, recent studies have disclosed severe and potentially lethal inflammatory manifestations of COVID-19 in children. We report the case of a 4-year-old child with a post-infectious multisystem inflammatory syndrome associated with COVID-19, with a Kawasaki-like shock and prominent neurologic features, for whom a cytokine storm and reduced brain-derived neurotrophic factor were well documented.


Assuntos
Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Síndrome de Resposta Inflamatória Sistêmica/complicações , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Pré-Escolar , Citocinas/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Inflamação , Pandemias , Síndrome de Resposta Inflamatória Sistêmica/patologia , Síndrome de Resposta Inflamatória Sistêmica/virologia
20.
Pain Physician ; 23(4S): S381-S390, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32942795

RESUMO

BACKGROUND: The interventional pain management community saw the COVID-19 pandemic decimate elective interventional procedures and new patient visits across the United States until the reopening of America and the restarting of interventional procedures and elective surgical procedures began again. Health care providers, along with essential workers and patients, continue to be concerned about functioning in a safe and responsible manner. Consequently, a level of comfort is created by the testing health care workers with long exposure to new patients and patients undergoing interventions in high risk environments. As the United States and the world suffers from an ongoing infodemic, there are substantial amounts of misinformation, and some appropriate information being produced on molecular, antigen and antibody testing. Consequently, this manuscript is undertaken to describe the value and validity of coronavirus antibody testing. METHODS: Literature review. RESULTS: Antibody tests detect antibodies or immunoglobulins that are produced as the human immune response to SARS-CoV-2 infection. A positive result suggests that the individual has potentially been exposed to SARS-CoV-2. When immunoglobulins M (IgM) antibodies are present, they can indicate an active or recent infection, whereas immunoglobulin G (IgG) antibodies show up later in the infection process and can often indicate a past infection, but does not exclude recently infected patients who can still be contagious, especially when IgM antibodies are also concurrently detected. While past knowledge indicates that for viral infections, IgG antibodies usually persist longer than IgM antibodies and provide immunity from re-infection, it is not clearly known if that is true for COVID-19. LIMITATIONS: A narrative review with paucity of literature. CONCLUSION: Antibody tests have been developed to detect IgG only, both IgG and IgM, or total antibodies. At present, multiple antibody tests are available for use in the United States. In a review of 54 available studies through the end of April, mostly from China, the accuracy of pooled results for combination IgG/IgM tests was 91.4% (95% CI, 87.0 - 96.6) for 15 to 21 days post-symptom onset. Thus, antibody tests provide a promise and a peril in the ongoing Covid-19 pandemic.


Assuntos
Anticorpos Antivirais/sangue , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Anticorpos Antivirais/imunologia , Betacoronavirus , China , Infecções por Coronavirus/sangue , Infecções por Coronavirus/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/imunologia , Sensibilidade e Especificidade
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