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

Author(s):  
Kohei Fujita ◽  
Shinpei Kada ◽  
Osamu Kanai ◽  
Hiroaki Hata ◽  
Takao Odagaki ◽  
...  

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.

2020 ◽  
Vol 8 ◽  
Author(s):  
Kohei Fujita ◽  
Shinpei Kada ◽  
Osamu Kanai ◽  
Hiroaki Hata ◽  
Takao Odagaki ◽  
...  

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.


2003 ◽  
Vol 10 (6) ◽  
pp. 1043-1050 ◽  
Author(s):  
Ketil Moen ◽  
Johan G. Brun ◽  
Tor Magne Madland ◽  
Turid Tynning ◽  
Roland Jonsson

ABSTRACT The objective of the present study was to investigate immunoglobulin G (IgG) and IgA antibody immune responses to Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus, and Candida albicans in the sera of patients with rheumatoid arthritis (RA), the synovial fluid (SF) of patients with RA (RA-SF samples), and the SF of patients without RA (non-RA-SF samples). An enzyme-linked immunosorbent assay was used to determine IgG and IgA antibody levels in 116 serum samples from patients with RA, 52 RA-SF samples, and 43 non-RA-SF samples; and these were compared with those in SF samples from 9 patients with osteoarthritis (OA-SF samples) and the blood from 100 donors (the control [CTR] group). Higher levels of IgG antibodies against B. forsythus (P < 0.0001) and P. intermedia (P < 0.0001) were found in non-RA-SF samples than in OA-SF samples, and higher levels of IgG antibodies against B. forsythus (P = 0.003) and P. intermedia (P = 0.024) were found in RA-SF samples than in OA-SF samples. Significantly higher levels of IgA antibodies against B. forsythus were demonstrated in both RA-SF and non-RA-SF samples than in OA-SF samples. When corrected for total Ig levels, levels of IgG antibody against B. forsythus were elevated in RA-SF and non-RA-SF samples compared to those in OA-SF samples. Lower levels of Ig antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group for both IgG (P = 0.003) and IgA (P < 0.0001). When corrected for total Ig levels, the levels of IgG and IgA antibodies against B. forsythus were still found to be lower in the sera from patients with RA than in the plasma of the CTR group (P < 0.0001). The levels of antibodies against P. gingivalis and C. albicans in the sera and SF of RA and non-RA patients were comparable to those found in the respective controls. The levels of IgG and IgA antibodies against B. forsythus were elevated in SF from patients with RA and non-RA-SF samples compared to those in OA-SF samples. Significantly lower levels of IgG and IgA antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group. This indicates the presence of an active antibody response in synovial tissue and illustrates a potential connection between periodontal and joint diseases.


2009 ◽  
Vol 16 (6) ◽  
pp. 906-915 ◽  
Author(s):  
Gabriela Hernández-Mora ◽  
Charles A. Manire ◽  
Rocío González-Barrientos ◽  
Elías Barquero-Calvo ◽  
Caterina Guzmán-Verri ◽  
...  

ABSTRACT Brucella ceti causes disease in Odontoceti. The absence of control serum collections and the diversity of cetaceans have hampered the standardization of serological tests for the diagnosis of cetacean brucellosis. Without a “gold” standard for sensitivity and specificity determination, an alternative approach was followed. We designed an indirect enzyme-linked immunosorbent assay (iELISA) that recognizes immunoglobulins G (IgGs) from 17 odontocete species as a single group. For the standardization, we used Brucella melitensis and Brucella abortus lipopolysaccharides, serum samples from seven resident odontocetes with no history of infectious disease displaying negative rose bengal test (RBT) reactions, and serum samples from seven dolphins infected with B. ceti. We compared the performance of the iELISA with those of the protein G ELISA (gELISA), the competitive ELISA (cELISA), and the immunofluorescence (IF) and dot blot (DB) tests, using 179 odontocete serum samples and RBT as the reference. The diagnostic potential based on sensitivity and specificity of the iELISA was superior to that of gELISA and cELISA. The correlation and agreement between the iELISA and the gELISA were relatively good (R i/g 2 = 0.65 and κi/g = 0.66, respectively), while the correlation and agreement of these two ELISAs with cELISA were low (R i/c 2 = 0.46, R g/c 2 = 0.37 and κi/c = 0.62, κg/c = 0.42). In spite of using the same anti-odontocete IgG antibody, the iELISA was more specific than were the IF and DB tests. An association between high antibody titers and the presence of neurological symptoms in dolphins was observed. The prediction is that iELISA based on broadly cross-reacting anti-dolphin IgG antibody would be a reliable test for the diagnosis of brucellosis in odontocetes, including families not covered in this study.


2021 ◽  
Author(s):  
Hari Ram Choudhary ◽  
Debaprasad Parai ◽  
Girish Chandra Dash ◽  
Jaya Singh Kshatri ◽  
Narayan Mishra ◽  
...  

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.


2021 ◽  
Author(s):  
Juan Manuel Carreño ◽  
Damodara Rao Mendu ◽  
Viviana Simon ◽  
Masood A Shariff ◽  
Gagandeep Singh ◽  
...  

AbstractSerological tests are important tools helping to determine previous infection with severe acute respiratory disease coronavirus 2 (SARS-CoV-2) and to monitor immune responses. The current tests are based on spike (S), the receptor binding domain (RBD), or the nucleoprotein (NP) as substrate. Here, we used samples from a high seroprevalence cohort of health care workers (HCWs) to perform a longitudinal analysis of the antibody responses using three distinct serological assays. 501 serum samples were tested using: a) a research-grade RBD and spike based tandem enzyme-linked immunosorbent assay (MS–RBD ELISA, MS-spike ELISA), b) a commercial RBD and spike based tandem ELISA (Kantaro-RBD, -spike), and c) a commercial NP-based chemiluminescent microparticle immunoassay (CMIA, Abbott Architect). Seroprevalence ranged around 28% during the early stage of the pandemic (a: 28.4% positives; b: 28.1%; c: 27.3%). Good correlation was observed between the MS and Kantaro RBD ELISAs and between the MS and Kantaro spike ELISAs. By contrast, modest correlations were observed between the Abbott Architect and both RBD and spike-based assays. A proportion of HCWs (n=178) were sampled again 3-5 months after the first time point. Although antibody levels declined in most of the positive individuals, the overall seroprevalence measured by RBD-spike based assays remained unchanged. However the seroprevalence of NP-reactive antibodies significantly declined. Lastly, we tested six samples of individuals who received two doses of SARS-CoV-2 mRNA vaccine and found that seroconversion was detected by the RBD-spike assays but – of course as expected - not the NP based assay. In summary, our results consolidate the strength of different serological assays to assess the magnitude and duration of antibodies to SARS-CoV-2.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Ernesta Cavalcanti ◽  
Maria Antonietta Isgrò ◽  
Domenica Rea ◽  
Lucia Di Capua ◽  
Giusy Trillò ◽  
...  

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.


2007 ◽  
Vol 15 (2) ◽  
pp. 297-302 ◽  
Author(s):  
Olga Sánchez Negrette ◽  
Fernando J. Sánchez Valdéz ◽  
Carlos D. Lacunza ◽  
María Fernanda García Bustos ◽  
María Celia Mora ◽  
...  

ABSTRACT Serological tests are the main laboratory procedures used for diagnosis during the indeterminate and chronic stages of Chagas' disease. A serological regression to negativity is the main criterion used to define parasitological cure in treated patients. The aim of this work was to monitor the individual specificities of antibody levels for 3 years posttreatment in 18 adult patients. Conventional serological techniques (hemagglutination assays and enzyme-linked immunosorbent assay [ELISA]) were modified by using recombinant antigens to detect early markers of treatment effectiveness. For this purpose, serum samples were taken before and during treatment and every 6 months after treatment for at least 3 years. When hemagglutination assays were used, a decrease in antibody levels was observed in only one patient. When ELISA with serum dilutions was used, antibody clearance became much more apparent: in 77.7% (14/18) of the patients, antibody titers became negative with time. This was observed at serum dilutions of 1/320 and occurred between the 6th and the 30th months posttreatment. The immune response and the interval for a serological regression to negativity were different for each patient. For some of the recombinant antigens, only 50% (9/18) of the patients reached the serological regression to negativity. Recombinant antigen 13 might be a good marker of treatment effectiveness, since 66.6% (six of nine) of the patients presented with an early regression to negativity for specific antibodies to this antigen (P = 0.002).


1988 ◽  
Vol 101 (2) ◽  
pp. 405-410 ◽  
Author(s):  
R. C. H Lau

SUMMARYEnzyme-linked immunosorbent assay (ELISA) tests were used to measure IgG antibody levels in 2638 New Zealand children who had been immunized with the triple vaccine DTP. The percentage of children immune to diphtheria decreased with age. The percentage of children immune to tetanus varied from 67.1 to 55.0%. The percentage of children with measurable antibody to pertussis increased with age. The mean percentages of children with measurable antibody or immunity to one or more DTP components were 34.2% (with 3 components), 34.4% (2 components), and 78.1% (1 component). It appears the immunization strategy for diphtheria and tetanus is satisfactory for herd immunity in New Zealand children. However, the current pertussis strategy may not be providing adequate immunity to 5-year-olds in this country.


2021 ◽  
Author(s):  
Yohannes Equar Messele ◽  
Gebrerufael Girmay ◽  
Bezina Arega Emeru ◽  
Shelema Kelbesa Bora ◽  
Workitu Firomsa Gudeta ◽  
...  

Abstract Background Reproductive problem is one of the main constraints of livestock genetic improvement efforts in tropical countries. The aim of this study was to determine the prevalence of major infectious causes of reproductive problems of dairy cattle in selected dairy farms in central Ethiopia. Overall 86 serum samples were collected from October 2018 to February 2019 from animals with history of reproductive problems. The collected serum was tested for antibody titer against Brucella species, Neospora caninum, Bovine Viral Diarrhea (BVD), Infectious Bovine Rhinotracheitis (IBR) and Q-fever using rose-bengal and enzyme-linked immunosorbent assay (ELISA) tests. Result Among the animals with the history of reproductive disordered; abortion, still birth and repeat breeding cases were found in 61.6%, 19.8% and 18.6%, respectively. The prevalence of IBR, BVD, Neospora caninum and Coxiella brunetti was found to be 79.1%, 38.4%, 3.5% and 1.2%, respectively. The combined infection of both BVD and IBR were detected in 21% of animals. Out of the total animals examined in this study, 95.9% of Jersey breeds were found seropositive to IBR than Boran-Friesian crosses (57.7%). The incidence of BVD was significantly higher in Boran-Friesian crossbred cattle than in Jersey which was found to be 69.3% and 14.3, respectively. The prevalence of IBR and BVD was directly proportional with age of the animal and parity. Conclusion Vaccination against IBR and BVD is not practiced in Ethiopia, the rising level of those diseases in dairy sector needs regular surveillance and control program.


Vaccines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 99
Author(s):  
Joanna Szczepanek ◽  
Monika Skorupa ◽  
Agnieszka Goroncy ◽  
Joanna Jarkiewicz-Tretyn ◽  
Aleksandra Wypych ◽  
...  

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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