scholarly journals High-throughput immunoassays for SARS-CoV-2, considerable differences in performance when comparing three methods

2020 ◽  
Author(s):  
Oskar Ekelund ◽  
Kim Ekblom ◽  
Sofia Somajo ◽  
Johanna Pattison-Granberg ◽  
Karl Olsson ◽  
...  
Keyword(s):  
High Throughput ◽  
Rapid Test ◽  
Performance Criteria ◽  
Clinical Use ◽  
Rt Pcr ◽  
Regulatory Authorities ◽  
Flow Test ◽  
Lateral Flow Test ◽  
High Level ◽  
Positive Results

Background: The recently launched high-throughput assays for the detection of antibodies against SARS-CoV-2 may change the managing strategies for the COVID-19 pandemic. This study aimed at investigating the performance of three high-throughput assays and one rapid lateral flow test relative to the recommended criteria defined by regulatory authorities. Methods: A total of 133 samples, including 100 pre-pandemic samples, 20 samples from SARS-CoV-2 RT-PCR positive individuals, and 13 potentially cross-reactive samples were analysed with SARS-CoV-2 IgG (Abbott), Elecsys Anti-SARS-CoV-2 (Roche), LIAISON SARS-CoV-2 S1/S2 IgG (DiaSorin) and 2019-nCOV IgG/IgM Rapid Test (Dynamiker Biotechnology Co). Results: All assays performed with a high level of specificity; however, only Abbott reached 100% (95% CI 96.3-100). The pre-pandemic samples analysed with Roche, DiaSorin and Dynamiker Biotechnology resulted in two to three false-positive results per method (specificity 96.9-98.0%). Sensitivity differed more between the assays, Roche exhibiting the highest sensitivity (100%, CI 83.9-100). The corresponding figures for Abbott, DiaSorin and Dynamiker Biotechnology were 85.0%, 77.8% and 75.0%, respectively. Conclusions: The results of the evaluated SARS-CoV-2 assays vary considerably as well as their ability to fulfil the performance criteria proposed by regulatory authorities. Introduction into clinical use in low-prevalent settings, should therefore, be made with caution.

scholarly journals 1775. A Community-wide Study to Evaluate the Accuracy of Self-testing for Influenza: Works in Progress

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S654-S654
Author(s):  
Matthew Thompson ◽  
Monica L Zigman Suchsland ◽  
Victoria Lyon ◽  
Enos Kline ◽  
ShiChu Huang ◽  
...  
Keyword(s):  
United States ◽  
Nasal Swab ◽  
Rapid Test ◽  
Test Strip ◽  
Lateral Flow ◽  
Reference Standard ◽  
Self Testing ◽  
Flow Test ◽  
Lateral Flow Test ◽  
At Home

Abstract Background Seasonal influenza (flu) occurs annually, causing disease with substantial morbidity and mortality. Currently, flu is suspected from clinical features, but requires a laboratory test to confirm infection. No influenza tests in the United States are approved for use outside of clinical settings. We aimed to determine the accuracy of influenza self-testing using an at-home, app-guided, lateral flow assay compared with a molecular reference standard conducted at a laboratory among adults self-reporting influenza-like illness (ILI). Methods This is an observational study of individuals with self-reported ILI throughout the continental 48 United States recruited from the Flu Near You platform, online marketing, and clinics in the Seattle area. Recruitment took place from March 4 to April 26, 2019. Participants were directed to an iPhone App that determined eligibility, consent, and responses to symptom questions and risk factors. Individuals were mailed a commercially available CLIA-waived influenza lateral flow test to conduct at home, guided by the app, and returned the used test along with a second nasal swab collected in viral transport media to the research team. Influenza testing was performed by RT–PCR on the second nasal swab, as well as the residual fluid from the RDT. Accuracy of home test result (read by the participant), as well as image capture of the lateral flow test strip, were compared with the lab-based reference standard. Results To date, 1127 at-home flu tests were mailed to participants and 711 (63.1%) samples returned to the lab. There were 17 flu-positive results from the rapid diagnostic test for a flu positivity rate of 2.4%. Testing using the reference standard is currently in progress. We will share diagnostic accuracy results once testing of the reference standard is completed. Of the kits returned, 353 (49.7%)had an error recorded, which included errors in return packaging, reference standard, rapid test tube sample, or rapid test strip errors. Conclusion Overall, findings from this study will determine the accuracy of an at-home rapid diagnostic test, and inform more widely research design for evaluating smartphone-enhanced home tests for pathogens. Many samples returned to the lab had a recorded error, suggesting at-home testing requires additional feasibility testing and refinement of the current methods used. Disclosures All authors: No reported disclosures.

scholarly journals Diagnostic Properties of Three SARS-CoV-2 Antibody Tests

Diagnostics ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1441
Author(s):  
Suelen Basgalupp ◽  
Giovana dos Santos ◽  
Marina Bessel ◽  
Lara Garcia ◽  
Ana Carolina de Moura ◽  
...  
Keyword(s):  
Rapid Test ◽  
Epidemiological Studies ◽  
Antibody Detection ◽  
Sample Collection ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Serological Tests ◽  
High Agreement ◽  
High Level ◽  
Antibody Tests

Serological assays emerged as complementary tools to RT-PCR in the diagnosis of SARS-CoV-2 as well as being needed for epidemiological studies. This study aimed to assess the performance of a rapid test (RT) compared to that of serological tests using finger prick blood samples. A total of 183 samples were evaluated, 88 of which were collected from individuals with negative RT-PCR and 95 from positive RT-PCR individuals. The diagnostic performance of RT (WONDFO®) and LUMIT (PROMEGA®) were compared to that of ELISA (EUROIMMUN®) for detecting antibodies against SARS-CoV-2 according to time from symptoms onset. The IgG antibody tests were detected in 77.4% (LUMIT), 77.9% (RT), and 80.0% (ELISA) of individuals. The detection of antibodies against SARS-CoV-2 increases in accordance with increasing time from symptoms onset. Considering only time from symptoms onset >21 days, the positivity rate ranged from 81.8 to 97.0% between the three tests. The RT and LUMIT showed high agreement with ELISA (agreement = 91.5%, k = 0.83, and agreement = 96.3%, k = 0.9, respectively) in individuals who had symptoms 15 to 21 days before sample collection. Compared to that of the ELISA assay, our results show sensitivity ranged from 95% to 100% for IgG antibody detection in individuals with symptoms onset between 15 and 21 days before sample collection. The specificity was 100% in individuals with symptoms onset >15 days before serological tests. This study shows good performance and high level of agreement of three immunoassays for the detection of SARS-CoV-2 antibodies.

scholarly journals Comparison of a qualitative canine C-reactive protein test to a quantitative test and traditional markers of inflammation — Short communication

2015 ◽  
Vol 63 (3) ◽  
pp. 317-322 ◽  
Author(s):  
Celia M. Smuts ◽  
Jennifer N. Mills ◽  
Tibor Gaál
Keyword(s):  
Acute Inflammation ◽  
Fibrinogen Concentration ◽  
C Reactive Protein ◽  
Serum Samples ◽  
Traditional Methods ◽  
Reactive Protein ◽  
Markers Of Inflammation ◽  
Flow Test ◽  
Lateral Flow Test ◽  
Positive Results

Qualitative tests for C-reactive protein (CRP) are available for use in dogs, and provide a rapid in-house method of detecting acute inflammation. The aim of this study was to compare results from a qualitative CRP lateral flow test (Teco CRP FASTest) to those obtained from a quantitative CRP ELISA and to traditional methods of detecting inflammation, including total leukocyte and neutrophil numbers, presence of immature neutrophils and a left shift, presence or absence of toxic changes in neutrophils and plasma fibrinogen concentration in whole blood and serum samples collected from 113 client-owned dogs. More dogs had CRP FASTest positive results than had quantitatively increased CRP (ELISA) or increases in traditional methods used for measuring inflammation. Few dogs had increases in markers of inflammation but no elevated CRP. The qualitative CRP FASTest was found to be a sensitive test for detecting increased CRP concentration and was positive more frequently than were traditional markers of inflammation.

scholarly journals Survey of filariasis and Microfilarial periodicity in Musi Rawas District, South Sumatra, Indonesia

2021 ◽  
Author(s):  
Erwin Edyansyah ◽  
Budi Mulyaningsih ◽  
Sitti R. Umniyati ◽  
Suwarno Hadisusanto
Keyword(s):  
Lymphatic Filariasis ◽  
Endemic Area ◽  
Rapid Test ◽  
Wuchereria Bancrofti ◽  
Parasitic Disease ◽  
Clinical Infection ◽  
Cross Sectional ◽  
Lymph System ◽  
High Level ◽  
Positive Results

Background: Lymphatic filariasis is a parasitic disease that is similar to the threads of its habitat in the lymph system that infect humans, namely Wuchereria bancrofti, Brugia malayi, and Brugia timori. Although B. malayi commonly infects humans, recent evidence also suggests that Brugia pahangi, an afilarial nematode naturally found in cats, can cause clinical infection in humans, with clinical features consistent with lymphatic filariasis. Methods: Cross-sectional with an observational and analytic approach. The results of a positive microscopic examination were carried out by Brugia Rapid Test for B. malayi and PCR examination for B. malayi and B. pahangi. Positive microscopic results were then checked for periodicity of microfilariae every 2 hours for 24 hoursResults: From the research, 17 people were positive for B. malayi microfilariae (mf rate 6.34%). The Brugia Rapid Test had 17 positive results. PCR results of 14 people were positive/formed a band at 322 bp. The results of the sample sequencing were B. malayi species. PCR results of B. pahangi were not found to be positive / band formed in all samples. The periodicity results of microfilaria peaked at 00: 00-04: 00 with the nocturnal periodic type. Conclusions: Lubuk Pauh Village, Musi Rawas Regency is still endemic for malayi filariasis with a high level of endemicity and is not an endemic area for filariasis pahangi. The periodicity of microfilariae indicates a nocturnal periodic type.

scholarly journals Updated Clinical Evaluation of the CLUNGENE® Rapid COVID-19 Antibody Test

Healthcare ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1124
Author(s):  
Christopher C. Lamb ◽  
Fadi Haddad ◽  
Christopher Owens ◽  
Alfredo Lopez-Yunez ◽  
Marion Carroll ◽  
...  
Keyword(s):  
False Positive ◽  
Point Of Care ◽  
Rapid Test ◽  
Antibody Test ◽  
Cross Reactivity ◽  
Blood Collection ◽  
Rt Pcr ◽  
Antibody Testing ◽  
Reactivity Study ◽  
Positive Results

Background: COVID-19 antibody testing has been shown to be predictive of prior COVID-19 infection and an effective testing tool. The CLUNGENE® SARS-COV-2 VIRUS (COVID-19) IgG/IgM Rapid Test Cassette was evaluated for its utility to aide healthcare professionals. Method: Two studies were performed by using the CLUNGENE® Rapid Test. (1) An expanded Point-of-Care (POC) study at two clinical sites was conducted to evaluate 99 clinical subjects: 62 positive subjects and 37 negative subjects were compared to RT-PCR, PPA, and NPA (95% CI). Sensitivity was calculated from blood-collection time following symptom onset. (2) A cross-reactivity study was performed to determine the potential for false-positive results from other common infections. Results: The specificity of subjects with confirmed negative COVID-19 by RT-PCR was 100% (95% CI, 88.4–100.0%). The sensitivity of subjects with confirmed positive COVID-19 by RT-PCR was 96.77% (95% CI, 88.98–99.11%). In the cross-reactivity study, there were no false-positive results due to past infections or vaccinations unrelated to the SARS-CoV-2 virus. Conclusion: There is a need for a rapid, user-friendly, and inexpensive on-site monitoring system for diagnosis. The CLUNGENE® Rapid Test is a useful diagnostic test that provides results within 15 min, without high-complexity laboratory instrumentation.

scholarly journals Diagnostic Accuracy of a New Antigen Test for SARS-CoV-2 Detection

2021 ◽  
Vol 18 (12) ◽  
pp. 6310
Author(s):  
Marina Di Domenico ◽  
Alfredo De Rosa ◽  
Francesca Di Gaudio ◽  
Pietro Internicola ◽  
Cinzia Bettini ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Test Methods ◽  
Lateral Flow ◽  
Diagnostic Tools ◽  
Nasopharyngeal Swab ◽  
Antigen Test ◽  
Rt Pcr ◽  
Promising Tool ◽  
Flow Test ◽  
Lateral Flow Test

Background and aims: Quick and reliable diagnostic tools play an important role in controlling the spread of the SARS-Cov-2 pandemic. The aim of this study was to evaluate the diagnostic accuracy of a new cyto-salivary antigen test aimed at detecting the presence of antigens for SARS-CoV-2, as compared by the gold standard RT-PCR and a lateral flow test. Methods: A total of 433 healthy volunteers were enrolled in the study and the sensitivity and specificity of the new cyto-salivary antigen test were calculated, as compared to the RT-PCR nasopharyngeal swab and to the lateral flow test. Results: A total of 433 samples were collected and tested at the Mediterranean Fair in Palermo from February 2021 until April 2021. The new cyto-salivary antigen had a sensitivity of 100% and a specificity of 94.2%. The sensitivity and the specificity of the lateral flow test were 55% and 100%, respectively. Conclusions: The new cyto-salivary antigen test detected more positive cases than the RT-PCR in a sample of asymptomatic subjects, demonstrating to be a promising tool for a more sensitive diagnosis of COVID-19. Further studies are warranted to better characterize its diagnostic accuracy.

Easy-to-Use Rapid Test for Direct Detection of Campylobacter spp. in Chicken Feces

2009 ◽  
Vol 72 (12) ◽  
pp. 2483-2488 ◽  
Author(s):  
M. WADL ◽  
T. PÖLZLER ◽  
G. FLEKNA ◽  
L. THOMPSON ◽  
J. SLAGHUIS ◽  
...  
Keyword(s):  
Direct Detection ◽  
Rapid Test ◽  
Developed Countries ◽  
Lateral Flow ◽  
Test Method ◽  
Campylobacter Coli ◽  
Flow Test ◽  
Chicken Feces ◽  
Lateral Flow Test ◽  
Campylobacter Spp

Human campylobacteriosis is the leading cause of acute bacterial gastroenteritis in developed countries. One important source of infection is poultry. Results from the Dutch Campylobacter Risk Management and Assessment project indicate that meat from broiler flocks shedding $7 log CFU Campylobacter per g of feces poses the greatest risk of transmitting campylobacteriosis. The objective of this study was to develop a simple and rapid test that would identify chicken flocks shedding high numbers of Campylobacter. We used lateral flow technology as the alternative test method, and selected the culture method according to International Organization for Standardization guidelines. To evaluate the test under field conditions, we sampled either chicken droppings at farms or cecal contents at the slaughterhouse. PCR was used to confirm presumptive Campylobacter spp. colonies. Under laboratory conditions, chicken feces containing $6.7 log CFU/g Campylobacter jejuni or $7.1 log CFU/g Campylobacter coli were identified by the lateral flow test. Overall, 3 (33%) of 10, and 29 (85%) of 34 C. jejuni–or C. coli–positive chicken flocks were identified at farms and slaughterhouses, respectively, by using the lateral flow test. Fecal samples containing $7.3 log of C. jejuni or C. coli CFU/g as determined by plating were always positive when using the lateral flow test. A single person testing seven flocks at a time could obtain test results within 2 h of sampling. This simple and rapid lateral flow test may contribute significantly to the identification of chicken flocks shedding high numbers of Campylobacter.

Covid-19: A review of its clinical features, effects on gastrointestinal system and possibility of faecal transmission

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 623-627
Author(s):  
Kanishk K Adhit ◽  
Anjankar Ashish P ◽  
Siddhaarth K
Keyword(s):  
Clinical Presentation ◽  
Throat Swab ◽  
Respiratory Illness ◽  
Review Article ◽  
Gastrointestinal System ◽  
Rt Pcr ◽  
Significant Evidence ◽  
Stool Samples ◽  
High Possibility ◽  
Positive Results

In China, Wuhan in the province of China, COVID-19 a patient suffering from pneumonia was tested and to identify the cause, the throat swab of the patient was tested. On 7th January 2020 WHO declared the identification as COVID-19. And then it was proclaimed as a pandemic. It classically causes a respiratory illness presenting as a mild cough, fever and . However, several investigators have advocated the involvement of the gastrointestinal tract and liver in COVID-19 infection similar to other infections. Further research studies have shown results that are expanding the possibility of transmission because RT-PCR assessment has shown significant evidence for the presence of virus not only in samples but also in stool samples. Studies have shown that virus in stool samples have got positive results even after the illness has resolved, and two respiratory tests were done 24 hours after COVID-19 being tested negative. The review article the different findings of the clinical presentation of COVID-19. It sheds light on the effects of COVID-19 in the gastrointestinal system along with the reasons for the high possibility of transmission of COVID-19 through the route.

scholarly journals Analytical Validation and Clinical Application of Rapid Serological Tests for SARS-CoV-2 Suitable for Large-Scale Screening

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 869
Author(s):  
Amedeo De Nicolò ◽  
Valeria Avataneo ◽  
Jessica Cusato ◽  
Alice Palermiti ◽  
Jacopo Mula ◽  
...  
Keyword(s):  
Early Diagnosis ◽  
Real Time Pcr ◽  
Large Scale ◽  
High Sensitivity ◽  
Analytical Validation ◽  
Pcr Assay ◽  
Serological Tests ◽  
Flow Test ◽  
Lateral Flow Test ◽  
Large Scale Screening

Recently, large-scale screening for COVID-19 has presented a major challenge, limiting timely countermeasures. Therefore, the application of suitable rapid serological tests could provide useful information, however, little evidence regarding their robustness is currently available. In this work, we evaluated and compared the analytical performance of a rapid lateral-flow test (LFA) and a fast semiquantitative fluorescent immunoassay (FIA) for anti-nucleocapsid (anti-NC) antibodies, with the reverse transcriptase real-time PCR assay as the reference. In 222 patients, LFA showed poor sensitivity (55.9%) within two weeks from PCR, while later testing was more reliable (sensitivity of 85.7% and specificity of 93.1%). Moreover, in a subset of 100 patients, FIA showed high sensitivity (89.1%) and specificity (94.1%) after two weeks from PCR. The coupled application for the screening of 183 patients showed satisfactory concordance (K = 0.858). In conclusion, rapid serological tests were largely not useful for early diagnosis, but they showed good performance in later stages of infection. These could be useful for back-tracing and/or to identify potentially immune subjects.

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