Comparison of Four Commercially Available Point-of-Care Tests to Detect Antibodies against Canine Parvovirus in Dogs

Measuring antibodies to evaluate dogs´ immunity against canine parvovirus (CPV) is useful to avoid unnecessary re-vaccinations. The study aimed to evaluate the quality and practicability of four point-of-care (POC) tests for detection of anti-CPV antibodies. The sera of 198 client-owned and 43 specific pathogen-free (SPF) dogs were included; virus neutralization was the reference method. Specificity, sensitivity, positive and negative predictive value (PPV and NPV), and overall accuracy (OA) were calculated. Specificity was considered to be the most important indicator for POC test performance. Differences between specificity and sensitivity of POC tests in the sera of all dogs were determined by McNemar, agreement by Cohen´s kappa. Prevalence of anti-CPV antibodies in all dogs was 80% (192/241); in the subgroup of client-owned dogs, it was 97% (192/198); and in the subgroup of SPF dogs, it was 0% (0/43). FASTest® and CanTiCheck® were easiest to perform. Specificity was highest in the CanTiCheck® (overall dogs, 98%; client-owned dogs, 83%; SPF dogs, 100%) and the TiterCHEK® (overall dogs, 96%; client-owned dogs, 67%; SPF dogs, 100%); no significant differences in specificity were observed between the ImmunoComb®, the TiterCHEK®, and the CanTiCheck®. Sensitivity was highest in the FASTest® (overall dogs, 95%; client-owned dogs, 95%) and the CanTiCheck® (overall dogs, 80%; client-owned dogs, 80%); sensitivity of the FASTest® was significantly higher compared to the one of the other three tests (McNemars p-value in each comparison: <0.001). CanTiCheck® would be the POC test of choice when considering specificity and practicability. However, differences in the number of false positive results between CanTiCheck®, TiterCHEK®, and ImmunoComb® were minimal.

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A rapid and affordable point of care test for antibodies against SARS-CoV-2 based on hemagglutination and artificial intelligence interpretation

Scientific Reports ◽

10.1038/s41598-021-04298-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vanessa Redecke ◽

Kazuki Tawaratsumida ◽

Erin T. Larragoite ◽

Elizabeth S. C. P. Williams ◽

Vicente Planelles ◽

...

Keyword(s):

Test Performance ◽

Learning Algorithm ◽

Point Of Care ◽

Method Comparison ◽

High Specificity ◽

Turnaround Time ◽

Analysis Tool ◽

Point Of Care Test ◽

Specificity And Sensitivity ◽

A Cell

AbstractDiagnostic tests that detect antibodies (AB) against SARS-CoV-2 for evaluation of seroprevalence and guidance of health care measures are important tools for managing the COVID-19 pandemic. Current tests have certain limitations with regard to turnaround time, costs and availability, particularly in point-of-care (POC) settings. We established a hemagglutination-based AB test that is based on bi-specific proteins which contain a dromedary-derived antibody (nanobody) binding red blood cells (RBD) and a SARS-CoV-2-derived antigen, such as the receptor-binding domain of the Spike protein (Spike-RBD). While the nanobody mediates swift binding to RBC, the antigen moiety directs instantaneous, visually apparent hemagglutination in the presence of SARS-CoV-2-specific AB generated in COVID-19 patients or vaccinated individuals. Method comparison studies with assays cleared by emergency use authorization demonstrate high specificity and sensitivity. To further increase objectivity of test interpretation, we developed an image analysis tool based on digital image acquisition (via a cell phone) and a machine learning algorithm based on defined sample-training and -validation datasets. Preliminary data, including a small clinical study, provides proof of principle for test performance in a POC setting. Together, the data support the interpretation that this AB test format, which we refer to as ‘NanoSpot.ai’, is suitable for POC testing, can be manufactured at very low costs and, based on its generic mode of action, can likely be adapted to a variety of other pathogens.

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Risk of bias and limits of reporting in diagnostic accuracy studies for commercial point-of-care tests for respiratory pathogens

Epidemiology and Infection ◽

10.1017/s0950268818000596 ◽

2018 ◽

Vol 146 (6) ◽

pp. 747-756

Author(s):

J.M. Hughes ◽

C. Penney ◽

S. Boyd ◽

P. Daley

Keyword(s):

Diagnostic Accuracy ◽

Test Performance ◽

Point Of Care ◽

Risk Of Bias ◽

Financial Impact ◽

Test Accuracy ◽

Respiratory Pathogens ◽

Study Results ◽

Group A ◽

Point Of Care Tests

AbstractCommercial point-of-care (POC) diagnostic tests for Group A Streptococcus, Streptococcus pneumoniae, and influenza virus have large potential diagnostic and financial impact. Many published reports on test performance, often funded by diagnostics companies, are prone to bias. The Standards for Reporting of Diagnostic Accuracy (STARD 2015) are a protocol to encourage accurate, transparent reporting. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool evaluates risk of bias and transportability of results. We used these tools to evaluate diagnostic test accuracy studies of POC studies for three respiratory pathogens. For the 96 studies analysed, compliance was <25% for 14/34 STARD 2015 standards, and 3/7 QUADAS-2 domains showed a high risk of bias. All reports lacked reporting of at least one criterion. These biases should be considered in the interpretation of study results.

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SARS-CoV-2 antibody seroprevalence in Lebanon: findings from the first nationwide serosurvey

BMC Infectious Diseases ◽

10.1186/s12879-022-07031-z ◽

2022 ◽

Vol 22 (1) ◽

Author(s):

Abbas Hoballah ◽

Rana El Haidari ◽

Ghina Siblany ◽

Fadi Abdel Sater ◽

Samir Mansour ◽

...

Keyword(s):

Test Performance ◽

Point Of Care ◽

Vaccination Campaign ◽

Herd Immunity ◽

Age Groups ◽

Rapid Test ◽

Population Based ◽

P Value ◽

Cumulative Number ◽

Population Weight

Abstract Background Lebanon, a small country in the Middle East, remains severely affected by the COVID-19 pandemic. Seroprevalence surveys of anti-SARS-CoV-2 antibodies provide accurate estimates of SARS-CoV-2 infection and hence evaluate the extent of the pandemic. The present study aimed to evaluate the prevalence of SARS-CoV-2 antibodies in Lebanon and to compare the estimated cumulative number of COVID-19 cases with the officially registered number of laboratory-confirmed cases up to January 15, 2021. Methods A nationwide population-based serosurvey study was conducted in Lebanon between December 7, 2020, and January 15, 2021, before the initiation of the national vaccination program. The nCOVID-19 IgG & IgM point-of-care (POCT) rapid test was used to detect the presence of anti-SARS-COV-2 immunoglobulin G (IgG) in the blood. Seroprevalence was estimated after weighting for sex, age, and area of residence and adjusting for the test performance. Results Of the 2058 participants, 329 were positive for IgG SARS-COV-2, resulting in a crude seroprevalence of 16.0% (95% CI 14.4–17.6). The weighed seroprevalence was 15.9% (95% CI of 14.4 and 17.4). After adjusting for test performance, the population weight-adjusted seroprevalence was 18.5% (95% CI 16.8–20.2). This estimate implies that 895,770 individuals of the general population were previously infected by COVID-19 up to January 15, 2021 in Lebanon. The overall estimated number of subjects with previous SARS-CoV-2 infection was three times higher than the officially reported cumulative number of confirmed cases. Seroprevalence was similar across age groups and sexes (p-value > 0.05). However, significant differences were revealed across governorates. Conclusions Our results suggest that the Lebanese population is still susceptible to SARS-CoV-2 infection and far from achieving herd immunity. These findings represent an important contribution to the surveillance of the COVID-19 pandemic in Lebanon and to the understanding of how this virus spreads. Continued surveillance for COVID-19 cases and maintaining effective preventive measures are recommended to control the epidemic spread in conjunction with a national vaccination campaign to achieve the desired level of herd immunity against COVID-19.

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Point-of-care tests for bovine clinical mastitis: what do we have and what do we need?

Journal of Dairy Research ◽

10.1017/s002202992000062x ◽

2020 ◽

Vol 87 (S1) ◽

pp. 60-66

Author(s):

Francisco B. Malcata ◽

P. Theo Pepler ◽

Emily L. O'Reilly ◽

Nicola Brady ◽

P. David Eckersall ◽

...

Keyword(s):

Test Performance ◽

Point Of Care ◽

Clinical Mastitis ◽

Antimicrobial Use ◽

Culture Independent ◽

Improved Performance ◽

Point Of Care Tests ◽

On Farm ◽

Mastitis Control

AbstractMastitis, inflammation of the bovine mammary gland, is generally caused by intramammary infection with bacteria, and antimicrobials have long been a corner stone of mastitis control. As societal concern about antimicrobial use in animal agriculture grows, there is pressure to reduce antimicrobial use in dairy farming. Point-of-care tests for on-farm use are increasingly available as tools to support this. In this Research Reflection, we consider available culture-dependent and culture-independent tests in the context of ASSURED criteria for low-resource settings, including convenience criteria, scientific criteria and societal criteria that can be used to evaluate test performance. As tests become more sophisticated and sensitive, we may be generating more data than we need. Special attention is given to the relationship between test outcomes and treatment decisions, including issues of diagnostic refinement, antimicrobial susceptibility testing, and detection of viable organisms. In addition, we explore the role of technology, big data and people in improved performance and uptake of point-of-care tests, recognising that societal barriers may limit uptake of available or future tests. Finally, we propose that the 3Rs of reduction, refinement and replacement, which have been used in an animal welfare context for many years, could be applied to antimicrobial use for mastitis control on dairy farms.

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Point of care testing using rapid automated antigen testing for SARS-COV-2 in care homes – an exploratory safety, usability and diagnostic agreement evaluation

Journal of Patient Safety and Risk Management ◽

10.1177/25160435211054207 ◽

2021 ◽

pp. 251604352110542

Author(s):

Massimo Micocci ◽

Peter Buckle ◽

Gail Hayward ◽

A Joy Allen ◽

Kerrie Davies ◽

...

Keyword(s):

Test Performance ◽

Point Of Care ◽

Care Home ◽

Immunofluorescence Assay ◽

Careful Consideration ◽

Care Homes ◽

Performance Study ◽

Post Modification ◽

Point Of Care Tests ◽

Positive Agreement

Introduction Successful adoption of POCTs (Point-of-Care tests) for COVID-19 in care homes requires the identification of ideal use cases and a full understanding of the contextual and usability factors that affect test results and minimise biosafety risks. This paper presents a scoping-usability and test performance study of a microfluidic immunofluorescence assay for COVID-19 in care homes. Methods A mixed-methods evaluation was conducted in four UK care homes to scope usability and to assess the agreement with qRT-PCR. A dry run with luminescent dye was conducted to explore biosafety issues. Results The agreement analysis was conducted on 227 asymptomatic participants (159 staff and 68 residents) and 14 symptomatic participants (5 staff and 9 residents). Asymptomatic specimens showed 50% (95% CI:1.3%−98.7%) positive agreement and 96% (95% CI: 92.5%−98.1%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.911 (95% CI: 0.857−0.965). Symptomatic specimens showed 83.3% (95% CI: 35.9%−99.6%) positive agreement and 100% (95% CI: 63.1%−100%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.857 (95% CI: 0.549−1). The dry run highlighted four main sources of contamination that led to the modification of the standard operating procedures. Simulation post-modification showed no further evidence of contamination. Conclusion Careful consideration of biosafety issues and contextual factors associated with care home are mandatory for safe use the POCT. Whilst POCT may have some utility for ruling out COVID-19, further diagnostic accuracy evaluations are needed to promote effective adoption.

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Point of Care Testing using rapid automated Antigen Testing for SARS-COV-2 in Care Homes – an exploratory safety, usability and diagnostic agreement evaluation

10.1101/2021.04.22.21255948 ◽

2021 ◽

Author(s):

Massimo Micocci ◽

Peter Buckle ◽

Gail Hayward ◽

A. Joy Allen ◽

Kerrie Davies ◽

...

Keyword(s):

Test Performance ◽

Point Of Care ◽

Care Home ◽

Immunofluorescence Assay ◽

Careful Consideration ◽

Care Homes ◽

Performance Study ◽

Mixed Methods Evaluation ◽

Point Of Care Tests ◽

Positive Agreement

AbstractIntroductionSuccessful adoption of POCTs (Point-of-Care tests) for COVID-19 in care homes requires the identification of ideal use cases and a full understanding of contextual and usability factors that affect test results and minimise biosafety risks. This paper presents findings from a scoping-usability and test performance study of a microfluidic immunofluorescence assay for COVID-19 in care homes.MethodsA mixed-methods evaluation was conducted in four UK care homes to scope usability and to assess the agreement with qRT-PCR. A dry run with luminescent dye was carried out to explore biosafety issues.ResultsThe agreement analysis was carried out on 227 asymptomatic participants (159 staff and 68 residents) and 14 symptomatic participants (5 staff and 9 residents). Asymptomatic specimens showed 50% (95% CI: 1.3%-98.7%) positive agreement and 96% (95% CI: 92.5%-98.1%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.911 (95% CI: 0.857-0.965). Symptomatic specimens showed 83.3% (95% CI: 35.9%-99.6%) positive agreement and 100% (95% CI: 63.1%-100%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.857 (95% CI: 0.549-1).The dry run showed four main sources of contamination that led to the modification of the standard operating procedures. Simulation after modification showed no further evidence of contamination.ConclusionCareful consideration of biosafety issues and contextual factors associated with care home are mandatory for safe use the POCT. Whilst POCT may have some utility for ruling out COVID-19, further diagnostic accuracy evaluations are needed to promote effective adoption.

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Diagnostic Accuracy and User-Friendliness of 5 Point-of-Care D-Dimer Tests for the Exclusion of Deep Vein Thrombosis

Clinical Chemistry ◽

10.1373/clinchem.2010.147892 ◽

2010 ◽

Vol 56 (11) ◽

pp. 1758-1766 ◽

Cited By ~ 25

Author(s):

Geert-Jan Geersing ◽

Diane B Toll ◽

Kristel JM Janssen ◽

Ruud Oudega ◽

Marloes JC Blikman ◽

...

Keyword(s):

Primary Care ◽

Diagnostic Accuracy ◽

Point Of Care ◽

Reference Method ◽

Roc Curves ◽

Color Contrast ◽

User Friendliness ◽

Predictive Values ◽

Point Of Care Tests ◽

D Dimer

BACKGROUND Point-of-care D-dimer tests have recently been introduced to enable rapid exclusion of deep venous thrombosis (DVT) without the need to refer a patient for conventional laboratory-based D-dimer testing. Before implementation in practice, however, the diagnostic accuracy of each test should be validated. METHODS We analyzed data of 577 prospectively identified consecutive primary care patients suspected to have DVT, who underwent 5 point-of-care D-dimer tests—4 quantitative (Vidas®, Pathfast™, Cardiac®, and Triage®) and 1 qualitative (Clearview Simplify®)—and ultrasonography as the reference method. We evaluated the tests for the accuracy of their measurements and submitted a questionnaire to 20 users to assess the user-friendliness of each test. RESULTS All D-dimer tests showed negative predictive values higher than 98%. Sensitivity was high for all point-of-care tests, with a range of 0.91 (Clearview Simplify) to 0.99 (Vidas). Specificity varied between 0.39 (Pathfast) and 0.64 (Clearview Simplify). The quantitative point-of-care tests showed similar and high discriminative power for DVT, according to calculated areas under the ROC curves (range 0.88–0.89). The quantitative Vidas and Pathfast devices showed limited user-friendliness for primary care, owing to a laborious calibration process and long analyzer warm-up time compared to the Cardiac and Triage. For the qualitative Clearview Simplify assay, no analyzer or calibration was needed, but interpretation of a test result was sometimes difficult because of poor color contrast. CONCLUSIONS Point-of-care D-dimer assays show good and similar diagnostic accuracy. The quantitative Cardiac and Triage and the qualitative Clearview Simplify D-dimer seem most user-friendly for excluding DVT in the doctor's office.

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Multicentre post-implementation assessment of the positive-predictive value of SARS-CoV-2 antigen-based point-of-care tests used for asymptomatic screening of continuing care staff

Journal of Clinical Microbiology ◽

10.1128/jcm.01411-21 ◽

2021 ◽

Author(s):

Jamil N Kanji ◽

Dustin T Proctor ◽

William Stokes ◽

Byron M Berenger ◽

James Silvius ◽

...

Keyword(s):

Positive Predictive Value ◽

Predictive Value ◽

Clinical Performance ◽

Point Of Care ◽

Reference Method ◽

Care Staff ◽

Continuing Care ◽

False Positive Detection ◽

Polymerase Chain ◽

Point Of Care Tests

Frequent screening of SARS-CoV-2 among asymptomatic populations using antigen-based point of care tests (APOCT) is occurring globally with limited clinical performance data. The positive predictive value (PPV) of two APOCT used in the asymptomatic screening of SARS-CoV-2 among healthcare workers (HCW) at continuing care (CC) sites across Alberta, Canada was evaluated. Between February 22 and May 2, 2021, CC sites implemented SARS-CoV-2 voluntary screening of their asymptomatic HCW. Onsite testing with Abbott Panbio or BD Veritor occurred on a weekly or twice weekly basis. Positive APOCT were confirmed with a real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) reference method. A total of 71,847 APOCT (17,689 Veritor and 54,158 Panbio) were performed among 369 CC sites. Eighty-seven (0.12%) APOCT were positive, of which 39 (0.05%) confirmed as true positives using rRT-PCR. Use of the Veritor and Panbio resulted in a 76.6% and 30.0% false positive detection, respectively (p<0.001). This corresponded to a 23.4% and 70.0% PPV for the Veritor and Panbio, respectively. Frequent screening of SARS-CoV-2 among asymptomatic HCW in CC, using APOCT, resulted in a very low detection rate and a high detection of false positives. Careful assessment between the risks vs benefits of APOCT programs and prevalence of infection in this population needs to be thoroughly considered before implementation.

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Comparison of Eight Commercially Available Faecal Point-of-Care Tests for Detection of Canine Parvovirus Antigen

Viruses ◽

10.3390/v13102080 ◽

2021 ◽

Vol 13 (10) ◽

pp. 2080

Author(s):

Julia Walter-Weingärtner ◽

Michèle Bergmann ◽

Karin Weber ◽

Uwe Truyen ◽

Cosmin Muresan ◽

...

Keyword(s):

Point Of Care ◽

Clinical Signs ◽

Kappa Statistic ◽

Laboratory Diagnosis ◽

Canine Parvovirus ◽

Predictive Values ◽

Shelter Dogs ◽

Low Sensitivity ◽

Sensitivity Specificity ◽

Point Of Care Tests

A real-time polymerase chain reaction (qPCR) is considered the gold standard for the laboratory diagnosis of canine parvovirus (CPV) infection but can only be performed in specialized laboratories. Several point-of-care tests (POCT), detecting CPV antigens in faeces within minutes, are commercially available. The aim of this study was to evaluate eight POCT in comparison with qPCR. Faecal samples of 150 dogs from three groups (H: 50 client-owned, healthy dogs, not vaccinated within the last four weeks; S: 50 shelter dogs, healthy, not vaccinated within the last four weeks; p = 50 dogs with clinical signs of CPV infection) were tested with eight POCT and qPCR. Practicability, sensitivity, specificity, positive (PPV) and negative predictive values (NPV), as well as overall accuracy were determined. To assess the differences between and agreement among POCT, McNemar’s test and Cohen’s Kappa statistic were performed. Specificity and PPV were 100.0% in all POCT. Sensitivity varied from 22.9–34.3% overall and from 32.7–49.0% in group P. VetexpertRapidTestCPVAg® had the highest sensitivity (34.3% overall, 49.0% group P) and differed significantly from the 3 POCT with the lowest sensitivities (Fassisi®Parvo (27.7% overall, 36.7% group P), Primagnost®ParvoH+K (24.3% overall, 34.7% group P), FASTest®PARVOCard (22.9% overall, 32.7% group P)). The agreement among all POCT was at least substantial (kappa >0.80). A positive POCT result confirmed the infection with CPV in unvaccinated dogs, whereas a negative POCT result did not definitely exclude CPV infection due to the low sensitivity of all POCT.

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Comparative Evaluation of cobas Influenza A/B & RSV and Simplexa Flu A/B & RSV for Rapid Detection of Influenza and Respiratory Syncytial Viruses

10.1101/2020.04.15.044099 ◽

2020 ◽

Author(s):

Kyu-Hwa Hur ◽

Heungsup Sung ◽

Mi-Na Kim

Keyword(s):

Influenza A ◽

Point Of Care ◽

False Negative ◽

Reference Method ◽

High Sensitivity ◽

Turnaround Time ◽

Continuous Variables ◽

Negative Results ◽

False Negative Results ◽

Point Of Care Tests

ABSTRACTWe compared two molecular point-of-care tests, the cobas Influenza A/B & RSV (cobas Liat) and the Simplexa Flu A/B & RSV (Simplexa). A total of 236 respiratory specimens from patients referred for respiratory viruses testing were retrospectively evaluated; 53 specimens tested positive for each of Flu A, Flu B, and RSV, and 77 specimens tested negative based on the results of the reference method, i.e. the Seegene Allplex Respiratory Panel 1/2/3 (Seegene, Seoul, Korea). The turnaround time (TAT) was 20 min per specimen for cobas Liat and 78 min per eight specimens for Simplexa. The numbers of invalid results were one (0.4%) in cobas Liat and 10 (4.2%) in Simplexa (p < 0.05). All results were consistent with those of the reference method in cobas Liat. The sensitivity and specificity for Flu A, Flu B and RSV A were 100% with Simplexa. However, the sensitivity for RSV B was 80.0% with Simplexa, which was significantly lower than that of cobas Liat (p < 0.05). Comparison of the cycle threshold (Ct) values for RSV with Simplexa and the reference method showed the correlation as continuous variables (p < 0.001) with a higher propensity for obtaining Ct values with Simplexa, the exception being the six false negative results; their Ct values were more than 30 in the reference method. Cobas Liat showed high sensitivity for the detection of RSV B with rapid TAT, and a good workflow efficiency.

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