Quantitative SARS-CoV-2 Antibody Screening of Healthcare Workers in the Southern Part of Kyoto City During the COVID-19 Pre-pandemic Period

Background: The coronavirus disease-2019 (COVID-19) pandemic is associated with a heavy burden on the mental and physical health of patients, regional healthcare resources, and global economic activity. While understanding of the incidence and case-fatality rates has increased, there are limited data concerning seroprevalence of antibodies against the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in healthcare workers during the pre-pandemic period. This study aimed to quantitatively evaluate seroprevalence of SARS-CoV-2 antibodies in healthcare workers in the southern part of Kyoto city, Japan.Methods: We prospectively recruited healthcare workers from a single hospital between April 10 and April 20, 2020. We collected serum samples from these participants and quantitatively evaluated SARS-CoV-2 IgG antibody levels using enzyme-linked immunosorbent assays.Results: Five (5.4%), 15 (16.3%), and 72 (78.3%) participants showed positive, borderline, and negative serum SARS-CoV-2 IgG antibody status, respectively. We found the mean titer associated with each antibody status (overall, positive, borderline, and negative) was clearly differentiated. Participants working at the otolaryngology department and/or with a history of seasonal common cold symptoms had a significantly higher SARS-CoV-2 IgG antibody titer (p = 0.046, p = 0.046, respectively).Conclusions: Five (5.4%) and 15 (16.3%) participants tested positive and borderline, respectively, for SARS-CoV-2 IgG antibody during the COVID-19 pre-pandemic period. These rates were higher than expected, based on government situation reports. These findings suggest that COVID-19 had already spread within the southern part of Kyoto city at the early stage of the pandemic.

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Quantitative SARS-CoV-2 antibody screening of healthcare workers in the southern part of Kyoto city during the COVID-19 peri-pandemic period

10.1101/2020.05.12.20098962 ◽

2020 ◽

Cited By ~ 1

Author(s):

Kohei Fujita ◽

Shinpei Kada ◽

Osamu Kanai ◽

Hiroaki Hata ◽

Takao Odagaki ◽

...

Keyword(s):

Healthcare Workers ◽

Early Stage ◽

Case Fatality ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Igg Antibody ◽

Kyoto City ◽

History Of ◽

Heavy Burden ◽

Antibody Levels

Background: The coronavirus disease-2019 (COVID-19) pandemic is associated with a heavy burden on the mental and physical health of patients, regional healthcare resources, and global economic activity. While our understanding of the incidence and case-fatality rates increases, data on seroprevalence of antibodies against the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in healthcare workers during the peri-pandemic period is insufficient. This study quantitatively evaluated seroprevalence of SARS-CoV-2 antibody in healthcare workers in the southern part of Kyoto city, Japan. Methods: We prospectively recruited healthcare workers from a single hospital between April 10 and April 20, 2020. We collected serum samples from these participants and quantitatively evaluated SARS-CoV-2 IgG antibody levels by enzyme-linked immunosorbent assay. Results: Five (5.4%), 15 (16.3%), and 72 (78.3%) participants showed positive, borderline, and negative serum SARS-CoV-2 IgG antibody status, respectively. We found the mean titer associated with each antibody status (overall, positive, borderline, and negative) was clearly differentiated. Participants working at the otolaryngology department and/or having a history of seasonal common cold symptoms had a significantly higher titer of SARS-CoV-2 IgG antibody (p=0.046, p=0.046, respectively). Conclusions: Five (5.4%) and 15 (16.3%) participants tested positive and borderline, respectively, for SARS-CoV-2 IgG antibody during the COVID-19 peri-pandemic period. These rates were higher than expected based on government situation reports. The present findings suggest that COVID-19 was already spread in the southern part of Kyoto city at the early stage of pandemic.

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Persistence of antibodies against Spike glycoprotein of SARS-CoV-2 in health care workers post double dose of BBV-152 and AZD1222 vaccines

10.21203/rs.3.rs-888762/v1 ◽

2021 ◽

Author(s):

Hari Ram Choudhary ◽

Debaprasad Parai ◽

Girish Chandra Dash ◽

Jaya Singh Kshatri ◽

Narayan Mishra ◽

...

Keyword(s):

Health Care ◽

Health Care Workers ◽

Serum Samples ◽

Igg Antibody ◽

Cross Sectional ◽

Post Vaccination ◽

Care Workers ◽

History Of ◽

Heath Care ◽

Antibody Levels

Abstract Rationale: Vaccine rollout in India was initiated in mid-January, 2021 and is supposed to be the only antidote against SARS-CoV-2 as of now.Objectives: To study the dynamicity of vaccine-induced IgG antibody against SARS-CoV-2.Methodology: The present cross-sectional cohort study was undertaken to determine IgG antibody among health care workers with completed dose of either Covaxin or Covishield and were followed for 24 weeks after first dose of either vaccine to record the periodic changes in titre, concentration, clinical growth and persistence of vaccine-induced SARS-CoV-2 antibodies.Results: Serum samples were collected from 614 participants during each follow-up and tested them in two CLIA-based platforms for testing SARS-CoV-2 antibodies both qualitatively and quantitatively. Among these participants, 308 (50.2%) were Covishield recipient and rest 306 (49.8%) took Covaxin. A total of 81 breakthrough cases was recorded among the cohort participants for whom infection post vaccination acted as booster. The rest 533 heath care workers without any history of post-vaccination infection showed significant antibody waning either from T3 (Covaxin recipient) or T4 (Covishield recipient).Conclusion: The clinical implications of waning antibody levels post vaccination are not well understood, and it remains crucial to establish S-antibody thresholds associated with protection against clinical outcomes.

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Vaccination strategy and anti - SARS-CoV-2 S titers in healthcare workers of the INT – IRCCS “Fondazione Pascale” Cancer Center (Naples, Italy)

Infectious Agents and Cancer ◽

10.1186/s13027-021-00375-2 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Ernesta Cavalcanti ◽

Maria Antonietta Isgrò ◽

Domenica Rea ◽

Lucia Di Capua ◽

Giusy Trillò ◽

...

Keyword(s):

Immune Response ◽

Immune Responses ◽

Healthcare Workers ◽

Geometric Mean ◽

Vaccination Strategy ◽

Antibody Responses ◽

Cancer Center ◽

Serum Samples ◽

Humoral Immune ◽

History Of

Abstract Background Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection and the resulting disease, coronavirus disease 2019 (COVID-19), have spread to millions of people globally, requiring the development of billions of different vaccine doses. The SARS-CoV-2 spike mRNA vaccine (named BNT162b2/Pfizer), authorized by the FDA, has shown high efficacy in preventing SARS-CoV-2 infection after administration of two doses in individuals 16 years of age and older. In the present study, we retrospectively evaluated the differences in the SARS-CoV-2 humoral immune response after vaccine administration in the two different cohorts of workers at the INT - IRCCS “Fondazione Pascale” Cancer Center (Naples, Italy): previously infected to SARS-CoV-2 subjects and not infected to SARS-CoV-2 subjects. Methods We determined specific anti-RBD (receptor-binding domain) titers against trimeric spike glycoprotein (S) of SARS-CoV-2 by Roche Elecsys Anti-SARS-CoV-2 S immunoassay in serum samples of 35 healthcare workers with a previous documented history of SARS-CoV-2 infection and 158 healthcare workers without, after 1 and 2 doses of vaccine, respectively. Moreover, geometric mean titers and relative fold changes (FC) were calculated. Results Both previously infected and not infected to SARS-CoV-2 subjects developed significant immune responses to SARS-CoV-2 after the administration of 1 and 2 doses of vaccine, respectively. Anti-S antibody responses to the first dose of vaccine were significantly higher in previously SARS-CoV-2-infected subjects in comparison to titers of not infected subjects after the first as well as the second dose of vaccine. Fold changes for subjects previously infected to SARS-CoV-2 was very modest, given the high basal antibody titer, as well as the upper limit of 2500.0 BAU/mL imposed by the Roche methods. Conversely, for naïve subjects, mean fold change following the first dose was low ($$ \overline{x} $$ x ¯ =1.6), reaching 3.8 FC in 72 subjects (45.6%) following the second dose. Conclusions The results showed that, as early as the first dose, SARS-CoV-2-infected individuals developed a remarkable and statistically significant immune response in comparison to those who did not contract the virus previously, suggesting the possibility of administering only one dose in previously SARS-CoV-2-infected subjects. FC for previously infected subjects should not be taken into account for the generally high pre-vaccination values. Conversely, FC for not infected subjects, after the second dose, were = 3.8 in > 45.0% of vaccinees, and ≤ 3.1 in 19.0%, the latter showing a potential susceptibility to further SARS-CoV-2 infection.

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Anti-SARS-CoV-2 IgG against the S Protein: A Comparison of BNT162b2, mRNA-1273, ChAdOx1 nCoV-2019 and Ad26.COV2.S Vaccines

Vaccines ◽

10.3390/vaccines10010099 ◽

2022 ◽

Vol 10 (1) ◽

pp. 99

Author(s):

Joanna Szczepanek ◽

Monika Skorupa ◽

Agnieszka Goroncy ◽

Joanna Jarkiewicz-Tretyn ◽

Aleksandra Wypych ◽

...

Keyword(s):

Cellular Response ◽

Protein A ◽

Humoral Response ◽

Blood Type ◽

Vaccine Response ◽

Serum Samples ◽

Igg Antibody ◽

Three Samples ◽

Nicolaus Copernicus ◽

Antibody Levels

Background: COVID-19 vaccines induce a differentiated humoral and cellular response, and one of the comparable parameters of the vaccine response is the determination of IgG antibodies. Materials and Methods: Concentrations of IgG anti-SARS-CoV-2 antibodies were analyzed at three time points (at the beginning of May, at the end of June and at the end of September). Serum samples were obtained from 954 employees of the Nicolaus Copernicus University in Toruń (a total of three samples each were obtained from 511 vaccinated participants). IgG antibody concentrations were determined by enzyme immunoassay. The statistical analysis included comparisons between vaccines, between convalescents and COVID-19 non-patients, between individual measurements and included the gender, age and blood groups of participants. Results: There were significant differences in antibody levels between mRNA and vector vaccines. People vaccinated with mRNA-1273 achieved the highest levels of antibodies, regardless of the time since full vaccination. People vaccinated with ChAdOx1 nCoV-2019 produced several times lower antibody levels compared to the mRNA vaccines, while the antibody levels were more stable. In the case of each of the vaccines, the factor having the strongest impact on the level and stability of the IgG antibody titers was previous SARS-CoV-2 infection. There were no significant correlations with age, gender and blood type. Summary: mRNA vaccines induce a stronger humoral response of the immune system with the fastest loss of antibodies over time.

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Longitudinal Analysis of Cryptosporidium Species-Specific Immunoglobulin G Antibody Responses in Peruvian Children

Clinical and Vaccine Immunology ◽

10.1128/cvi.13.1.123-131.2006 ◽

2006 ◽

Vol 13 (1) ◽

pp. 123-131 ◽

Cited By ~ 43

Author(s):

Jeffrey W. Priest ◽

Caryn Bern ◽

Lihua Xiao ◽

Jacquelin M. Roberts ◽

James P. Kwon ◽

...

Keyword(s):

Immunoglobulin G ◽

Antibody Responses ◽

Health Interventions ◽

Older Children ◽

Serum Samples ◽

Igg Antibody ◽

Specific Immunoglobulin ◽

Antibody Assays ◽

Species Specific ◽

Antibody Levels

ABSTRACT Cryptosporidium species are ubiquitous in the environment and are frequently detected in the stools of children who live where sanitation conditions are poor. To better characterize the immune response to these parasites, we monitored immunoglobulin G (IgG) antibody levels in a cohort of children from Lima, Peru. Two new enzyme-linked immunosorbent assays based on the C. parvum (bovine, subtype IIa) Iowa strain 17-kDa and 27-kDa antigens were used to measure IgG antibody levels in longitudinal serum samples. Antibody responses were detected during infections with C. parvum, C. felis, and C. meleagridis and with four different subtypes of C. hominis. We also noted that the magnitude of the antibody response was related to the number of previous infections and that older children generally had higher levels of antibodies to the two C. parvum antigens. Antibody responses were not associated with infections with either Cyclospora sp. or Giardia sp. We believe the antibody assays will be important tools for monitoring the success of future public health interventions.

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Prevalence and Haemolytic Significance of Red Cell Antibodies among Dangerous Universal Donors in a Tertiary Care Hospital in South India

International Journal of Medical Laboratory ◽

10.18502/ijml.v6i4.1998 ◽

2019 ◽

Author(s):

R Amita ◽

K Vijayalakshmi

Keyword(s):

Standard Procedure ◽

Tertiary Care ◽

Care Hospital ◽

Serum Samples ◽

Igg Antibody ◽

Voluntary Donor ◽

Antibody Titres ◽

Donor Population ◽

History Of ◽

Study Population

Background and Aims: A subgroup of group O individuals called ‘dangerous universal donors’ have immune (IgG) anti A and anti B antibodies which are active at 37˚C and capable of reacting with the red cells and causing lysis. The aim of this study was to find the prevalence of dangerous O group among the voluntary donor population and to assess the relation between the degree of haemolysis and the antibody titre. Materials and Methods: Group O donors excepting those with history of transfusion or pregnancy were included in the study. The serum samples were tested for haemolysins as per standard procedure. The degree of haemolysis was graded and strongly haemolytic samples were further characterised for the type of immunoglobulin class after treatment with dithiothretiol. The results were coded and analysed using SPSS software. Results: The age of the donors in this study ranged from 18 to 56 years. Majority were males. The prevalence of dangerous O group in our study population was found to be 10.75%. Within the dangerous O group samples, the titre of anti B IgG antibody was found to be higher than anti A IgG antibody. Titres for both anti A and anti B IgG antibodies ranged from 1:2 to 1:64. Conclusions: A simple screening for donor haemolysins will help in identification of strongly haemolytic samples, which are likely to have high titres of IgG, particularly anti A antibody. This will prevent transfusion of blood containing high titres of immune anti A and anti B antibodies to non O group recipients.

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Seroepidemiological Study of Toxocariasis in Children Aged 6-14 Year Old in Sanandaj, Western Iran

Iranian Journal of Parasitology ◽

10.18502/ijpa.v15i3.4209 ◽

2020 ◽

Author(s):

Yahya MAROUFI ◽

Ashkan FARIDI ◽

Mohammadbagher KHADEMERFAN ◽

Fares BAHRAMI ◽

Ghasem ZAMINI

Keyword(s):

Demographic Data ◽

Clinical Signs ◽

Cross Sectional Study ◽

Larva Migrans ◽

Serum Samples ◽

Igg Antibody ◽

Cross Sectional ◽

Medical Diagnostic ◽

History Of ◽

Low Prevalence

Background: Toxocariasis is a disease caused by Toxocara nematodes and occurs from consuming their eggs. The main hosts of these worms are dogs and cats. The disease in humans becomes a visceral larva migrans (VLM). This descriptive cross-sectional study was conducted to determine the prevalence of toxocariasis in children aged 6–14 years. Methods: This cross-sectional descriptive study was conducted from Jun 1 2016 to Dec 1 2017 in Sanandaj, west of Iran. A total of 182 serum samples were collected from children age 6 to14 yr referred to medical diagnostic laboratories. Demographic data (age, sex, and parents' literacy status), clinical signs (cough, headache, fever, abdominal pain), and the history of contact with dogs and cats was collected by a questionnaire. The presence of anti-Toxocara IgG antibody was detected by T. canis IgG ELISA (IBL, Germany) kit. Results: Of 182 subjects, 97 (53.3%) were male and 85 (46.7%) female. The average age was 9.2 years. Antibodies against T. canis were positive in three cases (1.65%) of all the studied subjects. Conclusions: The results showed a low prevalence of toxocariasis in children studied.

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Reactogenicity Correlates Only Weakly with Humoral Immunogenicity after COVID-19 Vaccination with BNT162b2 mRNA (Comirnaty®)

Vaccines ◽

10.3390/vaccines9101063 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1063

Author(s):

Jürgen Held ◽

Jan Esse ◽

Koray Tascilar ◽

Philipp Steininger ◽

Kilian Schober ◽

...

Keyword(s):

Linear Regression ◽

Regression Model ◽

Linear Regression Model ◽

Healthcare Workers ◽

Model Performance ◽

Neutralization Assay ◽

Spike Protein ◽

Igg Antibody ◽

Boost Vaccination ◽

Antibody Levels

mRNA vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), such as BNT162b2 (Comirnaty®), have proven to be highly immunogenic and efficient but also show marked reactogenicity, leading to adverse effects (AEs). Here, we analyzed whether the severity of AEs predicts the antibody response against the SARS-CoV-2 spike protein. Healthcare workers without prior SARS-CoV-2 infection, who received a prime-boost vaccination with BNT162b2, completed a standardized electronic questionnaire on the duration and severity of AEs. Serum specimens were collected two to four weeks after the boost vaccination and tested with the COVID-19 ELISA IgG (Vircell-IgG), the LIAISON® SARS-CoV-2 S1/S2 IgG CLIA (DiaSorin-IgG) and the iFlash-2019-nCoV NAb surrogate neutralization assay (Yhlo-NAb). A penalized linear regression model fitted by machine learning was used to correlate AEs with antibody levels. Eighty subjects were enrolled in the study. Systemic, but not local, AEs occurred more frequently after the boost vaccination. Elevated SARS-CoV-2 IgG antibody levels were measured in 92.5% of subjects with Vircell-IgG and in all subjects with DiaSorin-IgG and Yhlo-NAb. Gender, age and BMI showed no association with the antibody levels or with the AEs. The linear regression model identified headache, malaise and nausea as AEs with the greatest variable importance for higher antibody levels (Vircell-IgG and DiaSorin-IgG). However, the model performance for predicting antibody levels from AEs was very low for Vircell-IgG (squared correlation coefficient r2 = 0.04) and DiaSorin-IgG (r2 = 0.06). AEs did not predict the surrogate neutralization (Yhlo-NAb) results. In conclusion, AEs correlate only weakly with the SARS-CoV-2 spike protein antibody levels after COVID-19 vaccination with BNT162b2 mRNA.

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COMPARISON OF PERFORMANCE CHARACTERISTICS BETWEEN LATERAL FLOW, ELISA AND ELECTROCHEMILUMINESCENCE IMMUNOASSAYS FOR THE DETECTION OF SARS-COV-2 ANTIBODIES AMONG HEALTHCARE WORKERS

10.1101/2021.04.29.21256260 ◽

2021 ◽

Author(s):

M R Shincy ◽

Vandana Govindan ◽

H H Sudhakar ◽

V T Venkatesha ◽

K Padmapriya ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Healthcare Workers ◽

Care Pathway ◽

Point Of Care ◽

Lateral Flow ◽

Central Research ◽

Serum Samples ◽

Igg Antibody ◽

Human Igg ◽

Serological Tests

ABSTRACTBackgroundMedical professionals and researchers have been urging the need for wide and rapid testing of citizens in order to plan measures that can contain the spread of the virus. Antibody tests play an important role throughout the patient care pathway and are vital for the management and surveillance of the virus. Although RT-PCR is considered as the gold standard, serological tests based on antibodies are helpful for on-time detection. We performed one to one assessment of point-of-care lateral flow assay (POCTs), enzyme immunoassay (EIAs), electrochemiluminescence immunoassay (CLIA), to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG antibody.Materials and Methods611 healthcare workers were recruited between November and December 2020 at Central Research Laboratory, KIMS. Collected serum samples were analysed according to manufacturer’s protocol. The Standard Q IgG/IgM combo assay, Anti-SARS CoV-2 Human IgG ELISA, and the Elecsys® to measure the IgG titer of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).ResultsThe kits displayed a sensitivity of 61.2%,79.5%, 91.8% and specificity of 61.7%,64.1%,80.2% for the Standard Q IgG/IgM combo assay, Anti-SARS CoV-2 Human IgG ELISA, and the Elecsys® in order.ConclusionOur results indicate high sensitivity and specificity for the Elecsys® assay compared to Anti-SARS CoV-2 Human IgG ELISA, the Standard Q IgG/IgM combo assay.

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Distinct age-specific SARS-CoV-2 IgG decay kinetics following natural infection

10.1101/2021.08.05.21259465 ◽

2021 ◽

Author(s):

Calvin P Sjaarda ◽

Emily Moslinger ◽

Kyla Tozer ◽

Robert I Colautti ◽

Samira Kheitan ◽

...

Keyword(s):

Natural Infection ◽

Decay Rates ◽

Decay Kinetics ◽

Serum Samples ◽

Igg Antibody ◽

Multi Centre Study ◽

Viral Neutralization ◽

Antibody Levels ◽

Over Time

Background. Antibody responses to SARS-CoV-2 can be observed as early as 14 days post- infection, but little is known about the stability of antibody levels over time. Here we evaluate the long-term stability of anti-SARS-CoV-2 IgG antibodies following infection in 402 adult donors. Methods. We performed a multi-centre study carried out at Plasma Donor Centres in the city of Heidelberg (Plasmazentrum Heidelberg, Germany) and Munich (Plasmazentrum M&uumlnchen, Germany). We present anti-S/N and anti-N IgG antibody levels in prospective serum samples collected up to 403 days post recovery from SARS-CoV-2 infected individuals. Results: The cohort includes 402 adult donors (185 female, 217 male; 17 - 68 years of age) where anti-SARS-CoV-2 IgG levels were measured in plasma samples collected between 18- and 403-days post SARS-CoV-2 infection. A linear mixed effects model demonstrated IgG decay rates that decrease over time (χ2=176.8, p<0.00001) and an interaction of time*age (χ2=10.0, p<0.005)), with those over 60+ years showing the highest baseline IgG levels and the fastest rate of IgG decay. Baseline viral neutralization assays demonstrated that serum IgG levels correlated with in vitro neutralization capacity in 91% of our cohort. Conclusion. Long-term antibody levels and age-specific antibody decay rates suggest the potential need for age-specific vaccine booster guidelines to ensure long term vaccine protection against SARS-CoV-2 infection.

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