Performance analysis of rapid diagnostic tests on atypical bovine spongiform encephalopathy

The preferred method to determine the prevalence of bovine spongiform encephalopathy (BSE) in a country is to use immunology-based rapid-tests. Though these tests are validated to detect C-type BSE disease–associated prion (PrPsc), test-specific properties may influence their ability to detect H- and/or L-type BSE PrPsc, where both are atypical from C-type PrPsc. Molecular characterization shows atypical BSE PrPsc to have a different sensitivity to proteinase activity and different affinities for certain prion-specific antibodies. It is important to understand how atypical BSE PrPsc may affect the performance of rapid-tests, which are typically dependant on the use of specific proteases and antibodies. The current study used experimentally generated C-, H-, and L-type BSE PrPsc to evaluate 3 tests used in various national BSE surveillance programs: an immunochromatographic assay, a standard sandwich enzyme-linked immunosorbent assay (stndELISA), and a PrPsc-conformation–specific ELISA (confELISA). Although BSE PrPsc type had some effects on rapid-test performance, analytical sensitivity for atypical BSE PrPsc on all 3 platforms was not significantly compromised. When testing for atypical BSE PrPsc, the 3 tests were able to meet the same requirements that the European Food Safety Authority set when evaluating the tests for C-type BSE PrPsc.

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Continuous monitoring of bovine spongiform encephalopathy rapid test performance by weak positive tissue controls and quality control charts

Veterinary Microbiology ◽

10.1016/j.vetmic.2008.08.010 ◽

2009 ◽

Vol 134 (3-4) ◽

pp. 218-226 ◽

Cited By ~ 1

Author(s):

T SEUBERLICH ◽

M HOFMANN ◽

V JUILLERAT ◽

P BOUJON ◽

A ZURBRIGGEN ◽

...

Keyword(s):

Quality Control ◽

Bovine Spongiform Encephalopathy ◽

Test Performance ◽

Control Charts ◽

Continuous Monitoring ◽

Rapid Test ◽

Spongiform Encephalopathy ◽

Quality Control Charts

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Comparative Analysis of the Analytical Sensitivity of ELISA Test System DIA®-SARS-CoV-2-Ag-R with Rapid Tests for Viral Antigen SARS-CoV-2 Detection

Mikrobiolohichnyi Zhurnal ◽

10.15407/microbiolj83.03.066 ◽

2021 ◽

Vol 83 (3) ◽

pp. 66-71

Author(s):

А.Y. Horlov ◽

◽

V.H. Serdiuk ◽

О.K. Kiselova ◽

A.O. Shevchuk ◽

...

Keyword(s):

Viral Antigen ◽

False Negative ◽

Medical Science ◽

Rapid Test ◽

Test System ◽

Elisa Test ◽

Enzyme Linked Immunosorbent Assay ◽

Analytical Sensitivity ◽

Rapid Tests ◽

Positive Results

A novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease (COVID)-19, that emerged as a major pandemic. SARS-CoV-2 was identified as a betacoronavirus. Nucleocapsid protein (NP) is evolutionary high protein homologies and solid structure protein for SARS-CoV-2 detection as opposed to other proteins, that aren`t reliable as a single viral antigen during diagnostics methods. The viral RNA can be detected from nasal and pharyngeal swabs and bronchoalveolar lavage samples by PCR assay. However, the wrong collection of samples can lead to false-negative diagnosis and have dangerous consequences at this stage of pandemic. One of efficient and accurate methodological approaches for the screening of pathogens are serological assays. Aim. Evaluation and comparison of the sensitivity of invented DIA®-SARS-CoV-2-Ag-R enzyme-linked immunosorbent assay (ELISA)-based test system and commercial rapid tests, which detect the viral antigen of SARS-CoV-2. Methods. We carried out a comparison of DIA®-SARS-CoV-2-Ag-R and existed commercial test systems, which are used to detect the antigen of SARS-CoV-2 virus. Rapid tests are intended for nasopharyngeal swabs, but we proposed a protein of our own manufacture – recombinant NP as a calibrator. The detection limit was calibrated by standard CFAR #100982 NIBSC, UK. We had determined levels of NP (1400, 900, 750, 640 and 280 pg/mL) that we used as a sample for the rapid tests. The COVID-19 Ag Rapid Tests were performed according to the manufactures instructions at room temperature. Results. DIA®-SARS-CoV-2-Ag-R detected 10 pg/mL of in-house standard of recombinant SARS-CoV-2 NP. The positive results were observed using 1400, 900, 750 pg/mL, while 640 and 280 pg/mL samples were performed as negative in ABBOTT-PanBio test. The rapid tests manufactured by МBU, BIOTIME, Core Technology, SD BIOSENSOR and Turklab showed positive results only in 1400 pg/mL concentration. NP of lower levels was detected as a negative sample. The LEPU MEDICAL test was evaluated as positive sample using 900 pg/mL. The rapid test manufactured by Green Cross Medical Science Corp. showed negative results for all levels of NP. It can mean that the sensitivity of test is lower and demands higher level of antigen to detect the presence of SARS-CoV-2. Conclusions. The study presented an excellent analytical sensitivity of DIA®-SARS-CoV-2-Ag-R against commercial Antigen rapid tests. Thus, invented ELISA test system can be recommended for widespread usage for detection and confirmation of acute stage of SARS-CoV-2 infection.

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A Comparison of Rapid Bovine Spongiform Encephalopathy Testing Methods on Autolyzed Bovine Brain Tissue

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870501700201 ◽

2005 ◽

Vol 17 (2) ◽

pp. 99-102 ◽

Cited By ~ 9

Author(s):

Angus Wear ◽

Kirstine Henderson ◽

Kath Webster ◽

Indu Patel

Keyword(s):

Western Blot ◽

Bovine Spongiform Encephalopathy ◽

Bovine Brain ◽

Spongiform Encephalopathy ◽

The European Union ◽

Routine Testing ◽

New Methods ◽

Surveillance Programs ◽

The Eu ◽

Do So

In 1999, the European Union (EU) approved 3 rapid methods for the testing of bovine brain samples for the presence of bovine spongiform encephalopathy (BSE). The evaluation that led to the approval did not include an analysis of autolyzed material. Member states of the EU have active surveillance programs for BSE, which target fallen stock as well as other categories of cattle. Autolysis is a common feature of fallen stock samples because there can be a considerable delay between death and collection of samples. Therefore, it is important to know whether these tests perform optimally on autolyzed samples. The Veterinary Laboratories Agency (VLA) selected 250 positive fallen stock samples. These had been detected during routine testing using the Prionics®-Check Western blot and confirmed as BSE cases by immunohistochemistry or electron microscopy. Samples were graded according to the degree of autolysis and then tested by the 3 methods: Prionics®-Check Western blot, Platelia test, and Enfer test. All 3 methods correctly classified the samples as positive BSE cases, therefore alleviating doubt about their ability to do so. Subsequent EU validation exercises, such as those conducted in 2002–2003, have included the testing of autolyzed material. It is important that all new methods be evaluated on autolyzed tissue before approval for official use.

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PRNP and SPRN genes polymorphism in atypical bovine spongiform encephalopathy cases diagnosed in Polish cattle

Journal of Applied Genetics ◽

10.1007/s13353-012-0102-4 ◽

2012 ◽

Vol 53 (3) ◽

pp. 337-342 ◽

Cited By ~ 12

Author(s):

Artur Gurgul ◽

Mirosław Paweł Polak ◽

Magdalena Larska ◽

Ewa Słota

Keyword(s):

Bovine Spongiform Encephalopathy ◽

Spongiform Encephalopathy ◽

Atypical Bovine Spongiform Encephalopathy

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Transmissible spongiform encephalopathy in goats: is PrP rapid test sensitivity affected by genotype?

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638719896327 ◽

2020 ◽

Vol 32 (1) ◽

pp. 87-93 ◽

Cited By ~ 2

Author(s):

Marion M. Simmons ◽

Leigh Thorne ◽

Angel Ortiz-Pelaez ◽

John Spiropoulos ◽

Soteria Georgiadou ◽

...

Keyword(s):

Transmissible Spongiform Encephalopathy ◽

Small Ruminants ◽

Rapid Test ◽

Prnp Gene ◽

Spongiform Encephalopathy ◽

Sheep Population ◽

Test Sensitivity ◽

Goat Population ◽

Clinical Stages ◽

Rapid Tests

Transmissible spongiform encephalopathy (TSE) surveillance in goats relies on tests initially approved for cattle, subsequently assessed for sheep, and approval extrapolated for use in “small ruminants.” The current EU-approved immunodetection tests employ antibodies against various epitopes of the prion protein PrPSc, which is encoded by the host PRNP gene. The caprine PRNP gene is polymorphic, mostly at codons different from the ovine PRNP. The EU goat population is much more heterogeneous than the sheep population, with more PRNP-related polymorphisms, and with marked breed-related differences. The ability of the current tests to detect disease-specific PrPSc generated against these different genetic backgrounds is currently assumed, rather than proven. We examined whether common polymorphisms within the goat PRNP gene might have any adverse effect on the relative performance of EU-approved rapid tests. The sample panel comprised goats from the UK, Cyprus, France, and Italy, with either experimental or naturally acquired scrapie at both the preclinical and/or unknown and clinical stages of disease. Test sensitivity was significantly lower and more variable when compared using samples from animals that were preclinical or of unknown status. However, all of the rapid tests included in our study were able to correctly identify all samples from animals in the clinical stages of disease, apart from samples from animals polymorphic for serine or aspartic acid at codon 146, in which the performance of the Bio-Rad tests was profoundly affected. Our data show that some polymorphisms may adversely affect one test and not another, as well as underline the dangers of extrapolating from other species.

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Does the Presence of Scrapie Affect the Ability of Current Statutory Discriminatory Tests To Detect the Presence of Bovine Spongiform Encephalopathy?

Journal of Clinical Microbiology ◽

10.1128/jcm.00508-15 ◽

2015 ◽

Vol 53 (8) ◽

pp. 2593-2604 ◽

Cited By ~ 4

Author(s):

M. M. Simmons ◽

M. J. Chaplin ◽

C. M. Vickery ◽

S. Simon ◽

L. Davis ◽

...

Keyword(s):

Bovine Spongiform Encephalopathy ◽

Protein Misfolding ◽

Transmissible Spongiform Encephalopathy ◽

Cost Effective ◽

Phenotypic Characterization ◽

Enzyme Linked Immunosorbent Assay ◽

Spongiform Encephalopathy ◽

Cost Effective Alternative ◽

Variable Success

Current European Commission (EC) surveillance regulations require discriminatory testing of all transmissible spongiform encephalopathy (TSE)-positive small ruminant (SR) samples in order to classify them as bovine spongiform encephalopathy (BSE) or non-BSE. This requires a range of tests, including characterization by bioassay in mouse models. Since 2005, naturally occurring BSE has been identified in two goats. It has also been demonstrated that more than one distinct TSE strain can coinfect a single animal in natural field situations. This study assesses the ability of the statutory methods as listed in the regulation to identify BSE in a blinded series of brain samples, in which ovine BSE and distinct isolates of scrapie are mixed at various ratios ranging from 99% to 1%. Additionally, these current statutory tests were compared with a newin vitrodiscriminatory method, which uses serial protein misfolding cyclic amplification (sPMCA). Western blotting consistently detected 50% BSE within a mixture, but at higher dilutions it had variable success. The enzyme-linked immunosorbent assay (ELISA) method consistently detected BSE only when it was present as 99% of the mixture, with variable success at higher dilutions. Bioassay and sPMCA reported BSE in all samples where it was present, down to 1%. sPMCA also consistently detected the presence of BSE in mixtures at 0.1%. While bioassay is the only validated method that allows comprehensive phenotypic characterization of an unknown TSE isolate, the sPMCA assay appears to offer a fast and cost-effective alternative for the screening of unknown isolates when the purpose of the investigation was solely to determine the presence or absence of BSE.

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Infectivity in Skeletal Muscle of Cattle with Atypical Bovine Spongiform Encephalopathy

PLoS ONE ◽

10.1371/journal.pone.0031449 ◽

2012 ◽

Vol 7 (2) ◽

pp. e31449 ◽

Cited By ~ 19

Author(s):

Silvia Suardi ◽

Chiara Vimercati ◽

Cristina Casalone ◽

Daniela Gelmetti ◽

Cristiano Corona ◽

...

Keyword(s):

Skeletal Muscle ◽

Bovine Spongiform Encephalopathy ◽

Spongiform Encephalopathy ◽

Atypical Bovine Spongiform Encephalopathy

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Diagnostic accuracy of two commercial SARS-CoV-2 Antigen-detecting rapid tests at the point of care in community-based testing centers

10.1101/2020.11.20.20235341 ◽

2020 ◽

Cited By ~ 4

Author(s):

Alice Berger ◽

Marie Therese Ngo Nsoga ◽

Francisco Javier Perez-Rodriguez ◽

Yasmine Abi Aad ◽

Pascale Sattonnet-Roche ◽

...

Keyword(s):

Diagnostic Tests ◽

Point Of Care ◽

Rapid Test ◽

Diagnostic Value ◽

Rapid Diagnostic Tests ◽

Ease Of Use ◽

Rt Pcr ◽

Test Device ◽

Community Based ◽

Rapid Tests

AbstractBackgroundAntigen-detecting rapid diagnostic tests for SARS-CoV-2 offer new opportunities for the quick and laboratory-independent identification of infected individuals for control of the SARS-CoV-2 pandemic.MethodsWe performed a prospective, single-center, point of care validation of two antigen-detecting rapid diagnostic tests (Ag-RDT) in comparison to RT-PCR on nasopharyngeal swabs.FindingsBetween October 9th and 23rd, 2020, 1064 participants were enrolled. The Panbio™Covid-19 Ag Rapid Test device (Abbott) was validated in 535 participants, with 106 positive Ag-RDT results out of 124 positive RT-PCR individuals, yielding a sensitivity of 85.5% (95% CI: 78.0–91.2). Specificity was 100.0% (95% CI: 99.1–100) in 411 RT-PCR negative individuals. The Standard Q Ag-RDT (SD Biosensor, Roche) was validated in 529 participants, with 170 positive Ag-RDT results out of 191 positive RT-PCR individuals, yielding a sensitivity of 89.0% (95%CI: 83.7–93.1). One false positive result was obtained in 338 RT-PCR negative individuals, yielding a specificity of 99.7% (95%CI: 98.4–100). For individuals presenting with fever 1-5 days post symptom onset, combined Ag-RDT sensitivity was above 95%.InterpretationWe provide an independent validation of two widely available commercial Ag-RDTs, both meeting WHO criteria of ≥80% sensitivity and ≥97% specificity. Although less sensitive than RT-PCR, these assays could be beneficial due to their rapid results, ease of use, and independence from existing laboratory structures. Testing criteria focusing on patients with typical symptoms in their early symptomatic period onset could further increase diagnostic value.FundingFoundation of Innovative Diagnostics (FIND), Fondation privée des HUG, Pictet Charitable Foundation.

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