scholarly journals A longitudinal seroprevalence study in a large cohort of working adults reveals that neutralising SARS-CoV-2 RBD-specific antibodies persist for at least six months independent of the severity of symptoms

2020 ◽  
Author(s):  
Angelika Wagner ◽  
Angela Guzek ◽  
Johanna Ruff ◽  
Joanna Jasinska ◽  
Ute Scheikl ◽  
...  
Keyword(s):  
Specific Antibody ◽  
Large Scale ◽  
Antibody Test ◽  
Added Value ◽  
Lower Sensitivity ◽  
Neutralising Antibodies ◽  
Past Infection ◽  
Cross Sectional ◽  
Specific Antibodies ◽  
Iga Antibodies

AbstractBackgroundIn spring 2020, at the beginning of the first pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) wave in Europe, we set up an assay system for large-scale testing of virus-specific and protective antibodies including their longevity.MethodsWe analysed the sera of 1655 adult employees for SARS-CoV-2-specific antibodies using the S1 subunit of the spike protein of SARS-CoV-2. Sera containing S1-reactive antibodies were further evaluated for receptor-binding domain (RBD)- and nucleocapsid protein (NCP)-specific antibodies in relation to the neutralisation test (NT) results at 0, three and six months.FindingsWe found immunoglobulin G (IgG) and/or IgA antibodies reactive to the S1 protein in 10.15% (n=168) of the participants. In total, 0.97% (n=16) were positive for S1-IgG, 0.91% (n=15) were S1-IgG-borderline and 8.28% (n=137) exhibited only S1-IgA antibodies. Next, we evaluated the 168 S1-reactive sera for RBD- and NCP specificity: 8.33% (n=14) had detectable RBD-specific and 6.55% (n=11) NCP-specific antibodies. The latter correlated with NTs (kappa coefficient = 0.8660) but started to decline already after 3 months. RBD-specific antibodies correlated best with the NT (kappa = 0.9448) and only these antibodies were stable for up to six months. All participants with virus-neutralising antibodies reported symptoms, of which, anosmia and/or dysgeusia correlated best with the detection of virus-neutralising antibodies.InterpretationRBD-specific antibodies were most reliably detected post infection, independent of the number/severity of symptoms, and correlated best with protective neutralising antibodies at least for six months. They thus qualify best for large-scale seroepidemiological evaluation of both seroprevalence and seroprotection.FundingThis study received funding from the Austrian Ministry of Education, Science and Research within the research framework in relation to the coronavirus disease 2019 pandemic (GZ 2020 0225 104).Key pointsPersistence of SARS-CoV-2 antibodies depends on their specificity. Total RBD-specific antibodies are those that are stable for up to at least six months and correlate best with neutralisation independent of the presence and severity of COVID-19 symptoms.Research in contextEvidence before the studyAt the beginning of the study (early pandemic in April 2020), the SARS-Cov-2 specific seroprevalence was totally unknown. Additionally, S1-specific antibody assays being the first on the market were tested with limited sample size showing a lower sensitivity and specificity at that time. Furthermore, at that time, there were no unambiguous interpretations of antibody test results with regard to immunity/protection against reinfection. It was also not clear whether the detection of different antibody specificities could yield an essential input into the interpretation of the antibody’s qualities. Another open question was how long antibodies of the various specificities as well as antibodies with protective capacities would persist.Added value of this studyWe provide data to confirm the most reliable correlation of RBD-specific antibodies with neutralising antibodies that are stable for at least six months. S1- and NCP-specific antibodies wane more quickly than RBD-specific antibodies, rendering them not as ideal candidates for longitudinal seroprevalence studies. Concerning symptoms, anosmia/dysgeusia was strongly associated with NT-seropositivity and seroprotection in the overall study population.Implications of all the available evidenceOur data suggest that RBD-specific total antibody measurements with assays of high specificity can be used for cross-sectional as well as longitudinal seroepidemiological studies, even in low-prevalence settings. Detection of these antibodies also indicates robust seroprotection for at least six months. Due to the substantial loss of S1- and NCP-specific antibodies within the first months, assays targeting these antigen specificities – in contrast to RBD-specific antibody measurements – are not optimal to assess the duration of seroprotection. Overall, respiratory symptoms alone were not useful in predicting a past infection with SARS-CoV-2. However, anosmia/dysgeusia appeared to be a significant diagnostic marker, in particular for mild COVID-19.

scholarly journals Neutralising SARS-CoV-2 RBD-specific antibodies persist for at least six months independently of symptoms in adults

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Angelika Wagner ◽  
Angela Guzek ◽  
Johanna Ruff ◽  
Joanna Jasinska ◽  
Ute Scheikl ◽  
...  
Keyword(s):  
Nucleocapsid Protein ◽  
Large Scale ◽  
Kappa Coefficient ◽  
Receptor Binding Domain ◽  
Neutralising Antibodies ◽  
Specific Antibodies ◽  
Time Points ◽  
Large Scale Testing ◽  
Iga Antibodies ◽  
Set Up

Abstract Background In spring 2020, at the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Europe, we set up an assay system for large-scale testing of virus-specific and neutralising antibodies including their longevity. Methods We analysed the sera of 1655 adult employees for SARS-CoV-2-specific antibodies using the S1 subunit of the spike protein of SARS-CoV-2. Sera containing S1-reactive antibodies were further evaluated for receptor-binding domain (RBD)- and nucleocapsid protein (NCP)-specific antibodies in relation to the neutralisation test (NT) results at three time points over six months. Results We detect immunoglobulin G (IgG) and/or IgA antibodies reactive to the S1 protein in 10.15% (n = 168) of the participants. In total, 0.97% (n = 16) are positive for S1-IgG, 0.91% (n = 15) were S1-IgG- borderline and 8.28% (n = 137) exhibit only S1-IgA antibodies. Of the 168 S1-reactive sera, 8.33% (n = 14) have detectable RBD-specific antibodies and 6.55% (n = 11) NCP-specific antibodies. The latter correlates with NTs (kappa coefficient = 0.8660) but start to decline after 3 months. RBD-specific antibodies correlate most closely with the NT (kappa = 0.9448) and only these antibodies are stable for up to six months. All participants with virus-neutralising antibodies report symptoms, of which anosmia and/or dysgeusia correlate most closely with the detection of virus-neutralising antibodies. Conclusions RBD-specific antibodies are most reliably detected post-infection, independent of the number/severity of symptoms, and correlate with neutralising antibodies at least for six months. They thus qualify best for large-scale seroepidemiological evaluation of both antibody reactivity and virus neutralisation.

scholarly journals Detection of Specific Antibodies to an Antigenic Mannoprotein for Diagnosis of Penicillium marneffeiPenicilliosis

1998 ◽  
Vol 36 (10) ◽  
pp. 3028-3031 ◽  
Author(s):  
Liang Cao ◽  
Da-Liang Chen ◽  
Cindy Lee ◽  
Che-Man Chan ◽  
King-Man Chan ◽  
...  
Keyword(s):  
Specific Antibody ◽  
Blood Donors ◽  
Antibody Test ◽  
High Specificity ◽  
Pathogenic Fungi ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Specific Antibodies ◽  
Immunodeficiency Virus ◽  
Positive Results

The disseminated and progressive fungal disease Penicillium marneffei penicilliosis is one of the most common infectious diseases in AIDS patients in Southeast Asia. To diagnose systemic penicilliosis, we developed an enzyme-linked immunosorbent assay (ELISA)-based antibody test with Mp1p, a purified recombinant antigenic mannoprotein of P. marneffei. Evaluation of the test with guinea pig sera against P. marneffei and other pathogenic fungi indicated that this assay was specific for P. marneffei. Clinical evaluation revealed that high levels of specific antibody were detected in two immunocompetent penicilliosis patients. Furthermore, approximately 80% (14 of 17) of the documented penicilliosis patients with human immunodeficiency virus tested positive for the specific antibody. No false-positive results were found for serum samples from 90 healthy blood donors, 20 patients with typhoid fever, and 55 patients with tuberculosis, indicating a high specificity of the test. Thus, this ELISA-based test for the detection of anti-Mp1p antibody can be of significant value as a diagnostic for penicilliosis.

scholarly journals A High Through-put Assay for Circulating Antibodies Directed against the S Protein of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)

2020 ◽  
Author(s):  
Svenja Weiss ◽  
Jéromine Klingler ◽  
Catarina Hioe ◽  
Fatima Amanat ◽  
Ian Baine ◽  
...  
Keyword(s):  
Immune Response ◽  
Severe Acute Respiratory Syndrome ◽  
Large Scale ◽  
Magnetic Beads ◽  
Serum Antibody ◽  
Added Value ◽  
Past Infection ◽  
S Protein ◽  
Wide Range ◽  
Mount Sinai

SUMMARYBackgroundMore than one million infections with the severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) have been confirmed. While PCR-based assays are used for diagnosis, high through-put serologic methods are needed to detect antibodies for seroserveillance and for identification of seroconversion, potential plasma donors, and the nature of the immune response to this pathogen.MethodsA Luminex binding assay was used to assess the presence of antibodies in human sera from COVID-19-infected and -uninfected individuals specific for two recombinant proteins of SARS-CoV-2.FindingsFluorochrome-labeled beads were coated with a recombinant soluble stabilized trimeric SARS-CoV-2 S protein ectodomain or its central portion, the receptor binding domain (RBD). Coated beads were incubated with sera, followed by incubation with biotinylated anti-human total Ig antibodies and phycoerythrin (PE)-labeled streptavidin. Readout using a Luminex analyzer clearly differentiated between sera of the infected and uninfected subjects, delineating a wide range of serum antibody levels in infected subjects.InterpretationAntibody assays of sera can identify individuals who are infected with SARS-CoV-2 and have seroconverted, as well as subjects who have been infected and recovered. The use of the Luminex binding Ab assay has the advantage that it can be run in approximately 2.5 hours, uses very little antigen, and permits a high through-put of samples/day.FundingNIAID contracts and grants, Department of Veterans Affairs’ grants, the Microbiology Laboratory Clinical Services, Translational Science Hub, and Personalized Virology Initiative, and Department of Medicine of Mount Sinai Health System and Icahn School of Medicine at Mount Sinai.RESEARCH IN CONTEXTEvidence before this studyThe outbreak of infections with SARS-CoV-2 began in late 2019. Specimens from nasopharyngeal swabs are being used in PCR-based assays to test for the presence of the virus. Until the first week in April, 2020 there were no licensed tests for the presence of serum antibodies against proteins of the virus. The first approved tests are now becoming available, but none use a format that can be scaled up for mass screening which is now needed for implementing various public health measures. As per a recent Pubmed search, less than 10 studies using serologic assays have been published and none are high through-put.Added value of this studyHigh through-put antibody tests are needed in order to identify seroconversion, to perform serosurveys, identify potential donors for plasma therapy, assess the prevalence of infection in populations, identify healthcare workers who may be immune to SARS-CoV-2, and to study the nature of the immune response to this pathogen. The method described for detecting antibodies in SARS-CoV-2-infected patients can be applied in hospital and reference labs, allowing the assessment of present and past infection in a much higher number of donors per unit of time than assays described heretofore.Implications of all the available evidenceThis study shows that a test in which magnetic beads are coated with soluble forms of the spike protein of SARS-CoV-2 can be used to test for the presence of antibodies targeting this pathogen. The platform allows for the efficient testing of multiple specimens simultaneously using as little as 5 nanograms of antigen per test. This test affords the possibility of large scale, economical and efficient antibody testing.

scholarly journals Evaluation of a Multiplex Flow Immunoassay for Detection of Epstein-Barr Virus-Specific Antibodies

2008 ◽  
Vol 15 (9) ◽  
pp. 1410-1413 ◽  
Author(s):  
M. J. Binnicker ◽  
D. J. Jespersen ◽  
J. A. Harring ◽  
L. O. Rollins ◽  
E. M. Beito
Keyword(s):  
Specific Antibody ◽  
Epstein Barr Virus ◽  
Simultaneous Detection ◽  
Nuclear Antigen ◽  
Antibody Testing ◽  
Past Infection ◽  
Specific Antibodies ◽  
Barr Virus ◽  
Epstein Barr ◽  
Multiplex Bead

ABSTRACT Conventional methods for the detection of Epstein-Barr virus (EBV)-specific antibodies include the immunofluorescence assay (IFA) and enzyme immunoassay (EIA). While sensitive and specific, these methods are labor-intensive and require separate assays for each analyte. This study evaluated the performance of a multiplex bead assay (BioPlex 2200; Bio-Rad Laboratories, Hercules, CA) for the simultaneous detection of immunoglobulin G (IgG) and IgM class antibodies to the EBV viral capsid antigen (VCA) and IgG class antibodies to Epstein-Barr virus nuclear antigen-1 (EBNA-1). Serum specimens (n = 1,315) submitted for routine EBV-specific antibody testing by EIA (Grifols-Quest, Inc., Miami, FL) were also tested by the multiplex bead assay using the BioPlex 2200 automated analyzer. Specimens showing discordant results were tested by IFA. Following IFA resolution, the BioPlex VCA IgM, VCA IgG, and EBNA-1 IgG assays demonstrated 97.9%, 91.4%, and 96.9% agreement, respectively, with the results obtained by EIA. Furthermore, the BioPlex assays showed an overall agreement of 94.1% with the EIA when the specimens were categorized by disease state (susceptible, acute, or past infection) based on the EBV-specific antibody profiles. These findings indicate that the BioPlex EBV assays demonstrate a performance comparable to that of the conventional EIA, while allowing for a more rapid (2.3 h for 100 samples versus 4.5 h by the EIA) and higher-throughput (∼400 samples per 9 h versus 200 samples by the EIA) analysis of the EBV-specific antibody response.

Large-Scale Cross-Sectional Study of the Problem Areas in Diabetes Survey among Japanese Patients with Type 2 Diabetes Mellitus

Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 2393-PUB
Author(s):  
KENICHIRO TAKAHASHI ◽  
MINORI SHINODA ◽  
RIKA SAKAMOTO ◽  
JUN SUZUKI ◽  
TADASHI YAMAKAWA ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Large Scale ◽  
Japanese Patients ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
Diabetes Survey

Knowledge and awareness about MERS-CoV among the dental students in Chennai

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 847-851
Author(s):  
Nithyanandham Masilamani ◽  
Dhanraj Ganapathy
Keyword(s):  
College Students ◽  
Large Scale ◽  
Preventive Measures ◽  
Positive Impact ◽  
Educational Programs ◽  
Dental Students ◽  
Professional Organizations ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Mode Of Transmission

Middle East Respiratory Syndrome (MERS) induced by new ß coronavirus MERS-(CoV) had first been described in Saudi Arabia in September 2012. MERS-CoV communication inside the population is often identified with clustered households and cramped communal spaces. The purpose of the study is to assess the knowledge and awareness of MERS-CoV among dental students in India. This was a questionnaire-based cross-sectional survey of 100 dental college students in Chennai. The self-designed questionnaires contained ten questions focused on the knowledge and awareness of MERS-CoV amongst dental college students. Questionnaires were circulated through an online website survey planet. After the responses were received from 100 participants, data were collected and analyzed, .87% are aware of MERS-CoV through media 13% from professional channels. 84%are aware of the clinical manifestation of MERS-CoV. 81%Are aware of the mode of transmission of MERS-CoV. 76%are aware of the preventive measures against MERS -CoV.68%. Are aware of the incubation period of MERS-CoV. 74%aware of PCR as a diagnostic test for MERS-CoV. This study concluded that dental students had strong awareness and knowledge of MERS. Also, there are a few differences in information and behaviours that require change. Large-scale health educational programs on MERS also should be facilitated by professional organizations to expand their reach and to strengthen knowledge to have a positive impact on their behaviour.

Gambling-like video game practices: A cross-sectional study of links with problem gambling and disordered gaming

2019 ◽  
Author(s):  
David Zendle
Keyword(s):  
Video Games ◽  
Problem Gambling ◽  
Video Game ◽  
Large Scale ◽  
Significant Degree ◽  
Cross Sectional Study ◽  
Video Gaming ◽  
Cross Sectional ◽  
Streaming Services ◽  
Clinically Significant

A variety of practices have recently emerged which are related to both video games and gambling. Most prominent of these are loot boxes. However, a broad range of other activities have recently emerged which are also related to both gambling and video games: esports betting, real-money video gaming, token wagering, social casino play, and watching videos of both loot box opening and gambling on game streaming services like Twitch.Whilst a nascent body of research has established the robust existence of a relationship between loot box spending and both problem gambling and disordered gaming, little research exists which examines whether similar links may exist for the diverse practices outlined above. Furthermore, no research has thus far attempted to estimate the prevalence of these activities.A large-scale survey of a representative sample of UK adults (n=1081) was therefore conducted in order to investigate these issues. Engagement in all measured forms of gambling-like video game practices were significantly associated with both problem gambling and disordered gaming. An aggregate measure of engagement was associated with both these outcomes to a clinically significant degree (r=0.23 and r=0.43). Engagement in gambling-like video game practices appeared widespread, with a 95% confidence interval estimating that 16.3% – 20.9% of the population engaged in these activities at least once in the last year. Engagement in these practices was highly inter-correlated: Individuals who engaged in one practice were likely to engage in several more.Overall, these results suggest that the potential effects of the blurring of lines between video games and gambling should not primarily be understood to be due to the presence of loot boxes in video games. They suggest the existence of a convergent ecosystem of gambling-like video game practices, whose causal relationships with problem gambling and disordered gaming are currently unclear but must urgently be investigated.

Financial distress determinants among SMEs: empirical evidence from Sweden

2020 ◽  
Vol 47 (3) ◽  
pp. 547-560 ◽  
Author(s):  
Darush Yazdanfar ◽  
Peter Öhman
Keyword(s):  
Financial Crisis ◽  
Financial Distress ◽  
Large Scale ◽  
Global Financial Crisis ◽  
Binary Logistic Regression ◽  
Data Availability ◽  
Cross Sectional ◽  
Data Set ◽  
Content Type ◽  
The Global Financial Crisis

PurposeThe purpose of this study is to empirically investigate determinants of financial distress among small and medium-sized enterprises (SMEs) during the global financial crisis and post-crisis periods.Design/methodology/approachSeveral statistical methods, including multiple binary logistic regression, were used to analyse a longitudinal cross-sectional panel data set of 3,865 Swedish SMEs operating in five industries over the 2008–2015 period.FindingsThe results suggest that financial distress is influenced by macroeconomic conditions (i.e. the global financial crisis) and, in particular, by various firm-specific characteristics (i.e. performance, financial leverage and financial distress in previous year). However, firm size and industry affiliation have no significant relationship with financial distress.Research limitationsDue to data availability, this study is limited to a sample of Swedish SMEs in five industries covering eight years. Further research could examine the generalizability of these findings by investigating other firms operating in other industries and other countries.Originality/valueThis study is the first to examine determinants of financial distress among SMEs operating in Sweden using data from a large-scale longitudinal cross-sectional database.

scholarly journals Public Health Workforce Burnout in the COVID-19 Response in the U.S.

2021 ◽  
Vol 18 (8) ◽  
pp. 4369
Author(s):  
Kahler W. Stone ◽  
Kristina W. Kintziger ◽  
Meredith A. Jagger ◽  
Jennifer A. Horney
Keyword(s):  
Public Health ◽  
Health Workforce ◽  
Work Experience ◽  
Large Scale ◽  
Health Workers ◽  
Public Health Workforce ◽  
Cross Sectional Survey ◽  
Public Health Response ◽  
Cross Sectional ◽  
The U.S

While the health impacts of the COVID-19 pandemic on frontline health care workers have been well described, the effects of the COVID-19 response on the U.S. public health workforce, which has been impacted by the prolonged public health response to the pandemic, has not been adequately characterized. A cross-sectional survey of public health professionals was conducted to assess mental and physical health, risk and protective factors for burnout, and short- and long-term career decisions during the pandemic response. The survey was completed online using the Qualtrics survey platform. Descriptive statistics and prevalence ratios (95% confidence intervals) were calculated. Among responses received from 23 August and 11 September 2020, 66.2% of public health workers reported burnout. Those with more work experience (1–4 vs. <1 years: prevalence ratio (PR) = 1.90, 95% confidence interval (CI) = 1.08−3.36; 5–9 vs. <1 years: PR = 1.89, CI = 1.07−3.34) or working in academic settings (vs. practice: PR = 1.31, CI = 1.08–1.58) were most likely to report burnout. As of September 2020, 23.6% fewer respondents planned to remain in the U.S. public health workforce for three or more years compared to their retrospectively reported January 2020 plans. A large-scale public health emergency response places unsustainable burdens on an already underfunded and understaffed public health workforce. Pandemic-related burnout threatens the U.S. public health workforce’s future when many challenges related to the ongoing COVID-19 response remain unaddressed.

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