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

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

10.36106/ijsr/0101617 ◽

2021 ◽

pp. 45-48

Author(s):

Shincy M R ◽

Vandana Govindan ◽

Sudhakar H H ◽

Padmapriya K ◽

Venkatesha V T ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Healthcare Workers ◽

Care Pathway ◽

Point Of Care ◽

High Sensitivity ◽

Central Research ◽

Serum Samples ◽

Igg Antibody ◽

Human Igg ◽

Serological Tests

Background: The detection of SARS-CoV-2 IgG is important to determine the course of COVID-19. Medical 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 RTPCR is considered to be the gold standard, serological tests based on antibodies could be very helpful for on-time detection. We performed one to one assessment of electrochemiluminescence immunoassay, enzyme immunoassay (EIAs), and point-of-care lateral ow assay (POCTs) to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG antibody. Materials and Methods: 611 healthcare workers were recruited between November and December 2020 at Central Research Laboratory, KIMS. ® Collected serum samples were analysed using three commercially available assays: the Elecsys , Anti-SARS CoV-2 Human IgG ELISA, the Standard Q IgG/IgM combo assay following the manufacturer's protocol to measure the IgG titer of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Results:The kits displayed a sensitivity of 91.8%, 79.5% ,61.2% and a specicity of 80.2%, 64.1% ,61.7% in order. Conclusion: ® Our results indicate a high sensitivity and specicity for the Elecsys assay compared to Anti-SARS CoV-2 Human IgG ELISA, the Standard Q IgG/IgM combo assays.

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Comparative analysis of three point-of-care lateral flow immunoassays for detection of anti-SARS-CoV-2 antibodies in COVID-19 confirmed healthcare workers

10.1101/2020.11.11.20229914 ◽

2020 ◽

Author(s):

Danielle Dias Conte ◽

Joseane Mayara Almeida Carvalho ◽

Luciano Kleber de Souza Luna ◽

Klinger Soares Faíco-Filho ◽

Ana Helena Perosa ◽

...

Keyword(s):

Healthcare Workers ◽

Large Scale ◽

Point Of Care ◽

Antibody Test ◽

Cost Effective ◽

Lateral Flow ◽

Rt Pcr ◽

Serum Samples ◽

Igg Antibody ◽

Serological Tests

AbstractSince the Coronavirus Disease 2019 (COVID-19) pandemic, Brazil has the third-highest number of confirmed cases and the second-highest number of recovered patients. SARS-CoV-2 detection by real-time RT-PCR is the gold standard in certified infrastructured laboratories. However, for large-scale testing, diagnostics should be fast, cost-effective, widely available, and deployed for the community, such as serological tests based on lateral flow immunoassay (LFIA) for IgM/IgG detection. We evaluated three different commercial point-of-care (POC) LFIAs for anti-SARS-CoV-2 IgM and IgG detection in capillary whole blood of 100 healthcare workers (HCW) previously tested by RT-PCR: 1) COVID-19 IgG/IgM BIO (Bioclin, Brazil), 2) Diagnostic kit for IgM/IgG Antibody to Coronavirus (SARS-CoV-2) (Livzon, China); and 3) SARS-CoV-2 Antibody Test (Wondfo, China). A total of 84 positives and 16 negatives HCW were tested. The data was also analyzed by the number of days post symptoms (DPS) in three groups: <30 (n=26), 30-59 (n=42), and >59 (n=16). Overall detection was 85.71%, 47.62%, and 44.05% for Bioclin, Livzon, and Wondfo, respectively, with a specificity of 100%, and 98.75% for Livzon on storage serum samples. Bioclin was more sensitive (p<0.01), regardless of the DPS. Thus, the Bioclin can be used as a POC test to monitor SARS-CoV-2 seroconversion in HCW.

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COVID-19 Seroprevalence among Healthcare Workers of a Large COVID-19 Hospital in Rome Reveals Strengths and Limits of Two Different Serological Tests

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052650 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2650

Author(s):

Giuseppe Vetrugno ◽

Daniele Ignazio La Milia ◽

Floriana D’Ambrosio ◽

Marcello Di Pumpo ◽

Roberta Pastorino ◽

...

Keyword(s):

Blood Test ◽

Healthcare Workers ◽

Point Of Care ◽

Venous Blood ◽

Administrative Staff ◽

Serological Tests ◽

Predictive Values ◽

Work From Home ◽

Significant Difference ◽

Sensitivity Specificity

Healthcare workers are at the forefront against COVID-19, worldwide. Since Fondazione Policlinico Universitario A. Gemelli (FPG) IRCCS was enlisted as a COVID-19 hospital, the healthcare workers deployed to COVID-19 wards were separated from those with limited/no exposure, whereas the administrative staff were designated to work from home. Between 4 June and 3 July 2020, an investigation was conducted to evaluate the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin (IgG) antibodies among the employees of the FPG using point-of-care (POC) and venous blood tests. Sensitivity, specificity, and predictive values were determined with reverse-transcription polymerase chain reaction on nasal/oropharyngeal swabs as the diagnostic gold standard. The participants enrolled amounted to 4777. Seroprevalence was 3.66% using the POC test and 1.19% using the venous blood test, with a significant difference (p < 0.05). The POC test sensitivity and specificity were, respectively, 63.64% (95% confidence interval (CI): 62.20% to 65.04%) and 96.64% (95% CI: 96.05% to 97.13%), while those of the venous blood test were, respectively, 78.79% (95% CI: 77.58% to 79.94%) and 99.36% (95% CI: 99.07% to 99.55%). Among the low-risk populations, the POC test’s predictive values were 58.33% (positive) and 98.23% (negative), whereas those of the venous blood test were 92.86% (positive) and 98.53% (negative). According to our study, these serological tests cannot be a valid alternative to diagnose COVID-19 infection in progress.

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P342 Correlation of the first lateral flow-based Point of Care test to quantify infliximab and anti-infliximab antibodies in a finger prick sample with the reference ELISA technique

Journal of Crohn s and Colitis ◽

10.1093/ecco-jcc/jjab076.466 ◽

2021 ◽

Vol 15 (Supplement_1) ◽

pp. S366-S366

Author(s):

M B Ruiz-Argüello ◽

J Pascual ◽

L Del Río ◽

A Urigoitia ◽

C Balo Farto ◽

...

Keyword(s):

Correlation Coefficient ◽

Point Of Care ◽

Pearson Correlation ◽

Capillary Blood ◽

Lateral Flow ◽

Real Point ◽

Infliximab Treatment ◽

Serum Samples ◽

Finger Prick ◽

Elisa Technique

Abstract Background The goal of this study was to validate the use of capillary blood in a real point-of-care (POC) setting for patients under infliximab treatment by using Promonitor Quick lateral flow (LF) tests. Results were compared to the Promonitor ELISA reference technique in serum samples used by centralised laboratories. Methods A prospective, observational study was designed to evaluate the performance of a rapid LF test (Promonitor Quick IFX, Progenika, Spain). 160 infliximab treated rheumatology consecutive patients (400 samples) were recruited in two hospitals in Galicia, Spain. Prior to the infusion, a finger prick sample was obtained and analysed. Anti-infliximab antibodies were also determined with Promonitor Quick ANTI-IFX1-4. Results were read with the automated portable PQreader instrument. Additionally, a serum sample was collected for subsequent comparative analysis with either LF or ELISA tests. Qualitative (positive (PPA) and negative (NPA) agreements) and quantitative (Pearson correlation and bias) performance of the LF test was compared to ELISA, as well as between different specimens following CLSI EP09-A3. Results Overall agreement between Promonitor Quick IFX finger prick and ELISA test was 91% (88% PPA; 100% NPA). The quantitative comparison showed a good correlation (Pearson correlation coefficient: 0.85 and observed bias: 25%) (Table 1). Similar results were also observed when serum was used with either the LF or the ELISA tests (98% overall agreement, 0.91 correlation coefficient; 6% bias) (Table 1). Overall agreements for visual and automated (PQreader) interpretations with Promonitor Quick ANTI-IFX were 99% and 100% for finger prick and serum specimens, respectively (Table 2). Conclusion Promonitor Quick can be used to reliably quantify infliximab in capillary blood samples and results are comparable to those obtained with the reference ELISA technique. The use of the rapid POC test with finger prick will allow clinicians to monitor their patients in a fully decentralized mode to aid in the decision making process. PQreader is a sensitive portable equipment to report drug as well as antibody levels in the patient samples. References

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Gold nanoparticle-based lateral flow kit for in vitro detection of malaria antibodies

10.51415/10321/3185 ◽

2018 ◽

Author(s):

◽

Christian Lungani Mthembu

Keyword(s):

Test Line ◽

Point Of Care ◽

Three Dimensional ◽

Lateral Flow ◽

Igg Antibody ◽

Diagnostic Kits ◽

Test Kit ◽

Malaria Antigen ◽

And Performance

This study involves the development of three-dimensional dual lateral flow diagnostic assays. These assays were fabricated with quick response (QR) barcodes to ease the accessibility and transfer test data. The assays were designed to also improve the collection and transfer of survey from point-of-care facilities to centralized laboratories, thus, these would help to speed-up response to disease out-break. The study introduces the fabrication of two barcode based malaria diagnostic in the field of diagnostics. Two lateral flow kits were modified with two QR barcodes and three QR barcodes encoded with Google analytics codes for the detection and real-time tracking of malaria lateral flow which was designed to detect Plasmodium lactate dehydrogenase (pLDH). The fabrication of test kit was achieved by attaching two and three QR barcodes into two different test kits which were encoded with websites that were linked to Google analytics website as a tracking and performance monitor. Gold nanoparticles (AuNPs) were used as a substrate, where optical and structural properties were studied using UV/Visible spectroscopy, fluorescence spectroscopy, and transmission electron microscopy (TEM). The anti-mouse IgG antibody was used as a secondary antibody to act as control and the anti-(pLDH) was stripped on the test line. Phosphate buffer was used as a mobile phase solution. The antibody binding with pLDH antigen showed red test line indicating a positive test. Two diagnostic kits for rapid detection of pLDH were developed and validated for the detection of malaria antigen with lowest detectable recombinant concentration of 10 ng.mL-1. The diagnostic kits were incorporated with two and three optimally angled QR barcodes for identifying positive and negative. The second three QR barcode embedded test kit identified positive, negative and invalid using tracked website. These QR barcodes enabled massive results and tracking with precise location of the test through Google Analytics.

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Clinical Evaluation of a COVID-19 Antibody Lateral Flow Assay using Point of Care Samples

10.1101/2020.12.02.20242750 ◽

2020 ◽

Author(s):

Won Lee ◽

Steven Straube ◽

Ryan Sincic ◽

Jeanne A. Noble ◽

Juan Carlos Montoy ◽

...

Keyword(s):

Predictive Value ◽

Point Of Care ◽

Acute Infection ◽

High Specificity ◽

Lateral Flow ◽

Lateral Flow Immunoassay ◽

Onset Date ◽

Rt Pcr ◽

Serum Samples ◽

Antibody Positivity

ABSTRACTIntroductionThe ongoing SARS-CoV-2 pandemic has spurred the development of numerous point of care (PoC) immunoassays. Assessments of performance of available kits are necessary to determine their clinical utility. Previous studies have mostly performed these assessments in a laboratory setting, which raises concerns of translating findings for PoC use. The aim of this study was to assess the performance of a lateral flow immunoassay for the detection of SARS-CoV-2 antibodies using samples collected at PoC.MethodOne lateral flow immunoassay (Humasis® COVID-19 IgG/IgM) was tested. In total, 50 PCR RT-PCR positive and 52 RT-PCR negative samples were collected at PoC. Fifty serum specimens from Dec 2018 to Feb 2019 were used as controls for specificity. Serum samples collected between Dec 2019 to Feb 2020 were used as additional comparators. Clinical data including symptom onset date was collected from patient history and the medical record.ResultsThe overall sensitivity for the kit was 74% (95% CI: 59.7% -85.4%). The sensitivity for IgM and IgG detection >14 days after date of onset was 88% (95% CI: 68.8% -97.5%) and 84% (95% CI: 63.9% – 95.5%), with a negative predictive value (NPV) of 94% for IgM (95% CI: 83.5% - 98.8%) and 93% for IgG (95% CI: 81.8% - 97.9%). The overall specificity was 94% (95% CI: 83.5% - 98.8%). The Immunoglobulin specific specificity was 94% for IgM (95% CI: 83.5% - 98.8%) and 98% for IgG (95% CI: 89.4% - 100.0%), with a positive predictive value (PPV) of 88% for IgM (95% CI: 68.8% - 97.5%) and 95% for IgG (95% CI: 77.2% - 99.9%) respectively for samples collected from patients >14 days after date of onset. Specimen collected during early phase of COVID-19 pandemic (Dec 2019 to Feb 2020) showed 11.8% antibody positivity, and 11.3% of PCR-negative patients demonstrated antibody positivity.DiscussionHumasis® COVID-19 IgG/IgM LFA demonstrates greater than 90% PPV and NPV for samples collected 14 days after the onset of symptoms using samples collected at PoC. While not practical for the diagnosis of acute infection, the use of the lateral flow assays with high specificity may have utility for determining seroprevalence or seroconversion in longitudinal studies.

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Longitudinal Change of Severe Acute Respiratory Syndrome Coronavirus 2 Antibodies in Patients with Coronavirus Disease 2019

The Journal of Infectious Diseases ◽

10.1093/infdis/jiaa229 ◽

2020 ◽

Vol 222 (2) ◽

pp. 183-188 ◽

Cited By ~ 38

Author(s):

Guoxin Zhang ◽

Shuke Nie ◽

Zhaohui Zhang ◽

Zhentao Zhang

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Disease Onset ◽

Immunoglobulin M ◽

Longitudinal Change ◽

Igg Antibody ◽

Serological Tests ◽

Significant Difference ◽

Rapid Spread ◽

Novel Coronavirus ◽

Acid Test

Abstract Background A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently emerged and caused the rapid spread of coronavirus disease 2019 (COVID-19) worldwide. Methods We did a retrospective study and included COVID-19 patients admitted to Renmin Hospital of Wuhan University between 1 February and 29 February 2020. Antibody assay was conducted to detect COVID-19 envelope protein E and nucleocapsid protein N antigen. Results One hundred twelve patients were recruited with symptoms of fever, cough, fatigue, myalgia, and diarrhea. All patients underwent antibody tests. Fifty-eight (51.79%) were positive for both immunoglobulin M (IgM) and immunoglobulin G (IgG), 7 (6.25%) were negative for both antibodies, 1 (0.89%) was positive for only IgM, and 46 (41.07%) were positive for only IgG. IgM antibody appeared within a week post–disease onset, lasted for 1 month, and gradually decreased, whereas IgG antibody was produced 10 days after infection and lasted for a longer time. However, no significant difference in levels of IgM and IgG antibodies between positive and negative patients of nucleic acid test after treatment was found. Conclusions Our results indicate that serological tests could be a powerful approach for the early diagnosis of COVID-19.

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Development of Immunoassays for Detection of Francisella tularensis Lipopolysaccharide in Tularemia Patient Samples

Pathogens ◽

10.3390/pathogens10080924 ◽

2021 ◽

Vol 10 (8) ◽

pp. 924

Author(s):

Emily E. Hannah ◽

Sujata G. Pandit ◽

Derrick Hau ◽

Haley L. DeMers ◽

Kayleigh Robichaux ◽

...

Keyword(s):

Francisella Tularensis ◽

Point Of Care ◽

Natural Infection ◽

Lateral Flow ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Potential Threat ◽

Infectious Dose ◽

Antigen Capture ◽

Wide Range

Francisella tularensis is the causative agent of tularemia, a zoonotic bacterial infection that is often fatal if not diagnosed and treated promptly. Natural infection in humans is relatively rare, yet persistence in animal reservoirs, arthropod vectors, and water sources combined with a low level of clinical recognition make tularemia a serious potential threat to public health in endemic areas. F. tularensis has also garnered attention as a potential bioterror threat, as widespread dissemination could have devastating consequences on a population. A low infectious dose combined with a wide range of symptoms and a short incubation period makes timely diagnosis of tularemia difficult. Current diagnostic techniques include bacterial culture of patient samples, PCR and serological assays; however, these techniques are time consuming and require technical expertise that may not be available at the point of care. In the event of an outbreak or exposure a more efficient diagnostic platform is needed. The lipopolysaccharide (LPS) component of the bacterial outer leaflet has been identified previously by our group as a potential diagnostic target. For this study, a library of ten monoclonal antibodies specific to F. tularensis LPS were produced and confirmed to be reactive with LPS from type A and type B strains. Antibody pairs were tested in an antigen-capture enzyme-linked immunosorbent assay (ELISA) and lateral flow immunoassay format to select the most sensitive pairings. The antigen-capture ELISA was then used to detect and quantify LPS in serum samples from tularemia patients for the first time to determine the viability of this molecule as a diagnostic target. In parallel, prototype lateral flow immunoassays were developed, and reactivity was assessed, demonstrating the potential utility of this assay as a rapid point-of-care test for diagnosis of tularemia.

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

Frontiers in Public Health ◽

10.3389/fpubh.2020.595348 ◽

2020 ◽

Vol 8 ◽

Cited By ~ 1

Author(s):

Kohei Fujita ◽

Shinpei Kada ◽

Osamu Kanai ◽

Hiroaki Hata ◽

Takao Odagaki ◽

...

Keyword(s):

Healthcare Workers ◽

Early Stage ◽

Case Fatality ◽

Serum Samples ◽

Igg Antibody ◽

Kyoto City ◽

History Of ◽

Heavy Burden ◽

Antibody Levels ◽

Mental And Physical Health

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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Serological Diagnosis of Brucella Infections in Odontocetes

Clinical and Vaccine Immunology ◽

10.1128/cvi.00413-08 ◽

2009 ◽

Vol 16 (6) ◽

pp. 906-915 ◽

Cited By ~ 11

Author(s):

Gabriela Hernández-Mora ◽

Charles A. Manire ◽

Rocío González-Barrientos ◽

Elías Barquero-Calvo ◽

Caterina Guzmán-Verri ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Brucella Melitensis ◽

Enzyme Linked Immunosorbent Assay ◽

Dot Blot ◽

Serum Samples ◽

Igg Antibody ◽

Serological Tests ◽

Diagnostic Potential ◽

Control Serum ◽

History Of

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.

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