Head-to-head comparison of SARS-CoV-2 antigen-detecting rapid test with professional-collected anterior nasal versus nasopharyngeal swab

AbstractBackgroundNasopharyngeal (NP) swab samples for antigen-detecting rapid diagnostic tests (Ag-RDTs) require qualified healthcare professionals and are frequently perceived as uncomfortable by patients.MethodsWe performed a manufacturer-independent, prospective diagnostic accuracy study, comparing professional-collected anterior nasal (AN) to nasopharyngeal swab, using the test kits of a WHO-listed SARS-CoV-2 Ag-RDT (STANDARD Q COVID-19 Ag Test, SD Biosensor), which is also being distributed by Roche. Individuals with high suspicion for COVID-19 infection were tested. The reference standard was RT-PCR using a combined oro-/nasopharyngeal swab sample. Percent positive and negative agreement, as well as sensitivity and specificity were calculated.ResultsAmong the 179 participants, 41 (22.9%) tested positive for SARS-CoV-2 by RT-PCR. The positive percent agreement of the two different sampling techniques for the Ag-RDT was 93.5% (CI 79.3-98.2). The negative percent agreement was 95.9% (CI 91.4-98.1). The Ag-RDT with AN-sampling showed a sensitivity of 80.5% (33/41 PCR positives detected; CI 66.0-89.8) and specificity of 98.6% (CI 94.9-99.6) compared to RT-PCR. The sensitivity with NP-sampling was 73.2% (30/41 PCR positives detected; CI 58.1-84.3) and specificity was 99.3% (CI 96.0-100). In patients with high viral load (>7.0 log10 RNA SARS-CoV2/swab), the sensitivity of the Ag-RDT with AN-sampling was 100% and 94.7% with NP-sampling.ConclusionThis study demonstrates that sensitivity of a WHO-listed SARS-CoV-2 Ag-RDT using a professional AN-sampling kit is at least equal to that of the NP-sampling kit, although confidence intervals overlap. Of note, differences in the IFUs of the test procedures could have contributed to different sensitivities. AN-sampling can be performed with less training, reduces patient discomfort, and it enables scaling of antigen testing strategies. Additional studies of patient self-sampling should be considered to further facilitate the scaling-up of Ag-RDT testing.

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Head-to-head comparison of SARS-CoV-2 antigen-detecting rapid test with self-collected anterior nasal swab versus professional-collected nasopharyngeal swab

10.1101/2020.10.26.20219600 ◽

2020 ◽

Cited By ~ 11

Author(s):

Andreas K. Lindner ◽

Olga Nikolai ◽

Franka Kausch ◽

Mia Wintel ◽

Franziska Hommes ◽

...

Keyword(s):

Point Of Care ◽

Rapid Test ◽

High Viral Load ◽

Ease Of Use ◽

Healthcare Personnel ◽

Nasopharyngeal Swab ◽

Swab Sample ◽

Rt Pcr ◽

Percent Agreement ◽

Accuracy Study

AbstractBackgroundTwo antigen-detecting rapid diagnostic tests (Ag-RDTs) are now approved through the WHO Emergency Use Listing procedure and can be performed at the point-of-care. However, both tests use nasopharyngeal (NP) swab samples. NP swab samples must be collected by trained healthcare personnel with protective equipment and are frequently perceived as uncomfortable by patients.MethodsThis was a manufacturer-independent, prospective diagnostic accuracy study with comparison of a supervised, self-collected anterior nose (AN) swab sample with a professional-collected NP swab sample, using a WHO-listed SARS-CoV-2 Ag-RDT, STANDARD Q COVID-19 Ag Test (SD Biosensor), which is also being distributed by Roche. The reference standard was RT-PCR from an oro-/nasopharyngeal swab sample. Percent positive and negative agreement as well as sensitivity and specificity were calculated.ResultsAmong the 289 participants, 39 (13.5%) tested positive for SARS-CoV-2 by RT-PCR. The positive percent agreement of the two different sampling techniques for the Ag-RDT was 90.6% (CI 75.8-96.8). The negative percent agreement was 99.2% (CI 97.2-99.8). The Ag-RDT with AN sampling showed a sensitivity of 74.4% (29/39 PCR positives detected; CI 58.9-85.4) and specificity of 99.2% (CI 97.1-99.8) compared to RT-PCR. The sensitivity with NP sampling was 79.5% (31/39 PCR positives detected; CI 64.5-89.2) and specificity was 99.6% (CI 97.8-100). In patients with high viral load (>7.0 log 10 RNA SARS-CoV2/swab), the sensitivity of the Ag-RDT with AN sampling was 96% and 100% with NP sampling.ConclusionSupervised self-sampling from the anterior nose is a reliable alternative to professional nasopharyngeal sampling using a WHO-listed SARS-CoV-2 Ag-RDT. Considering the ease-of-use of Ag-RDTs, self-sampling and potentially patient self-testing at home may be a future use case.

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Anterior nasal versus nasal mid-turbinate sampling for a SARS-CoV-2 antigen-detecting rapid test: does localisation or professional collection matter?

10.1101/2021.02.09.21251274 ◽

2021 ◽

Cited By ~ 2

Author(s):

Olga Nikolai ◽

Chiara Rohardt ◽

Frank Tobian ◽

Andrea Junge ◽

Victor M. Corman ◽

...

Keyword(s):

Diagnostic Accuracy ◽

Rapid Test ◽

Nasopharyngeal Swab ◽

Diagnostic Accuracy Study ◽

Rt Pcr ◽

Percent Agreement ◽

Accuracy Study ◽

Polymerase Chain ◽

Sensitivity Specificity ◽

Antigen Testing

AbstractObjectivesThe aim of this diagnostic accuracy study was direct comparison of two different nasal sampling methods for an antigen-based rapid diagnostic test (Ag-RDT) that detects severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Furthermore, the accuracy and feasibility of self-sampling was evaluated.MethodsThis manufacturer-independent, prospective diagnostic accuracy study, compared professional anterior nasal (AN) and nasal mid-turbinate (NMT) sampling for a WHO-listed SARS-CoV-2 Ag-RDT. A second group of participants collected a NMT sample themselves and underwent a professional nasopharyngeal swab for comparison. The reference standard was real-time polymerase chain reaction (RT-PCR) using combined oro-/nasopharyngeal sampling. Individuals with high suspicion of SARS-CoV-2 infection were tested. Sensitivity, specificity, and percent agreement were calculated. Self-sampling was observed without intervention. Feasibility was evaluated by observer and participant questionnaires.ResultsAmong 132 symptomatic adults, both professional AN- and NMT-sampling yielded a sensitivity of 86.1% (31/36 RT-PCR positives detected; 95%CI: 71.3-93.9) and a specificity of 100.0% (95%CI: 95.7-100). The positive percent agreement (PPA) was 100% (95%CI: 89.0-100). Among 96 additional adults, self NMT- and professional NP-sampling yielded an identical sensitivity of 91.2% (31/34; 95%CI 77.0-97.0). Specificity was 98.4% (95%CI: 91.4-99.9) with NMT- and 100.0% (95%CI: 94.2-100) with NP-sampling. The PPA was 96.8% (95%CI: 83.8-99.8). Most participants (85.3%) considered self-sampling as easy to perform.ConclusionProfessional AN- and NMT-sampling are of equivalent accuracy for an Ag-RDT in ambulatory symptomatic adults. Participants were able to reliably perform the NMT-sampling themselves, following written and illustrated instructions. Nasal self-sampling will likely facilitate scaling of SARS-CoV-2 antigen testing.

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SARS-CoV-2 patient self-testing with an antigen-detecting rapid test: a head-to-head comparison with professional testing

10.1101/2021.01.06.20249009 ◽

2021 ◽

Author(s):

Andreas K. Lindner ◽

Olga Nikolai ◽

Chiara Rohardt ◽

Franka Kausch ◽

Mia Wintel ◽

...

Keyword(s):

Extraction Procedure ◽

Rapid Test ◽

High Viral Load ◽

Ease Of Use ◽

Rt Pcr ◽

Design Procedures ◽

Percent Agreement ◽

Self Testing ◽

Accuracy Study ◽

Instructions For Use

Background Antigen-detecting rapid diagnostic tests (Ag-RDTs) have been widely recommended as a complement to RT-PCR. Considering the possibility of nasal self-sampling and the ease-of-use in performing the test, self-testing may be an option. Methods and Findings We performed a manufacturer-independent, prospective diagnostic accuracy study of nasal mid-turbinate self-sampling and self-testing when using a WHO-listed SARS-CoV-2 Ag-RDT. Symptomatic participants suspected to have COVID-19 received written and illustrated instructions. Procedures were observed without intervention. For comparison, Ag-RDTs with nasopharyngeal sampling were professionally performed. Estimates of agreement, sensitivity, and specificity relative to RT-PCR on a combined oro-/nasopharyngeal sample were calculated. Feasibility was evaluated by observer and participant questionnaires. Among 146 symptomatic adults, 40 (27.4%) were RT-PCR-positive for SARS-CoV-2. Sensitivity with self-testing was 82.5% (33/40 RT-PCR positives detected; 95% CI 68.1-91.3), and 85.0% (34/40; 95% CI 70.9-92.9) with professional testing. The positive percent agreement between self-testing and professional testing on Ag-RDT was 91.4% (95% CI 77.6-97.0), and negative percent agreement 99.1% (95% CI 95.0-100). At high viral load (>7.0 log10 SARS-CoV-2 RNA copies/ml), sensitivity was 96.6% (28/29; 95% CI 82.8-99.8) for both self- and professional testing. Deviations in sampling and testing (incomplete self-sampling or extraction procedure, or imprecise volume applied on the test device) were observed in 25 out of the 40 PCR-positives. Participants were rather young (mean age 35 years) and educated (59.6% with higher education degree). Most participants (80.9%) considered the Ag-RDT as rather easy to perform. Conclusion Ambulatory participants suspected for SARS-CoV-2 infection were able to reliably perform the Ag-RDT and test themselves. Procedural errors might be reduced by refinement of the Ag-RDTs for self-testing, such as modified instructions for use or product design/procedures. Self-testing may result in more wide-spread and more frequent testing. Paired with the appropriate information and education of the general public about the benefits and risks, self-testing may therefore have significant impact on the pandemic.

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Head-to-head performance comparison of self-collected nasal versus professional-collected nasopharyngeal swab for a WHO-listed SARS-CoV-2 antigen-detecting rapid diagnostic test

Medical Microbiology and Immunology ◽

10.1007/s00430-021-00710-9 ◽

2021 ◽

Author(s):

Julian A. F. Klein ◽

◽

Lisa J. Krüger ◽

Frank Tobian ◽

Mary Gaeddert ◽

...

Keyword(s):

High Viral Load ◽

Performance Comparison ◽

World Health ◽

Nasopharyngeal Swab ◽

Rapid Diagnostics ◽

Sample Collection ◽

Rt Pcr ◽

Percent Agreement ◽

Polymerase Chain ◽

Health Organization

AbstractIn 2020, the World Health Organization (WHO) recommended two SARS-CoV-2 lateral flow antigen-detecting rapid diagnostics tests (Ag-RDTs), both initially with nasopharyngeal (NP) sample collection. Independent head-to-head studies are necessary for SARS-CoV-2 Ag-RDT nasal sampling to demonstrate comparability of performance with nasopharyngeal (NP) sampling. We conducted a head-to-head comparison study of a supervised, self-collected nasal mid-turbinate (NMT) swab and a professional-collected NP swab, using the Panbio™ Ag-RDT (distributed by Abbott). We calculated positive and negative percent agreement between the sampling methods as well as sensitivity and specificity for both sampling techniques compared to the reference standard reverse transcription polymerase chain reaction (RT-PCR). A SARS-CoV-2 infection could be diagnosed by RT-PCR in 45 of 290 participants (15.5%). Comparing the NMT and NP sampling the positive percent agreement of the Ag-RDT was 88.1% (37/42 PCR positives detected; CI 75.0–94.8%). The negative percent agreement was 98.8% (245/248; CI 96.5–99.6%). The overall sensitivity of Panbio with NMT sampling was 84.4% (38/45; CI 71.2–92.3%) and 88.9% (40/45; CI 76.5–95.5%) with NP sampling. Specificity was 99.2% (243/245; CI 97.1–99.8%) for both, NP and NMT sampling. The sensitivity of the Panbio test in participants with high viral load (> 7 log10 SARS-CoV-2 RNA copies/mL) was 96.3% (CI 81.7–99.8%) for both, NMT and NP sampling. For the Panbio supervised NMT self-sampling yields comparable results to NP sampling. This suggests that nasal self-sampling could be used for to enable scaled-up population testing.Clinical Trial DRKS00021220.

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Validation of the Panbio™ COVID-19 Antigen Rapid Test (Abbott) to screen for SARS-CoV-2 infection in Sint Maarten: a diagnostic accuracy study

10.1101/2021.09.23.21260526 ◽

2021 ◽

Author(s):

Colin King ◽

Eva Lista-de Weever ◽

Maria Henry ◽

Radjin Steingrover ◽

Chérina Fleming ◽

...

Keyword(s):

Diagnostic Accuracy ◽

Close Contact ◽

Rapid Test ◽

Nasopharyngeal Swab ◽

Rt Pcr ◽

The Public ◽

Negative Results ◽

Accuracy Study ◽

Antigen Tests ◽

Dutch Caribbean

AbstractObjectivesControl of the pandemic has required countries to look for other forms of tests besides the gold standard real-time polymerase chain reaction (RT-PCR). Rapid antigen tests (RAT), though less sensitive than RT-PCR, offer the possibility of rapid, inexpensive and early detection of the most infectious COVID-19 cases. Only very few studies have assessed the performance of the Abbott Panbio COVID-19 RAT among asymptomatic people or in Latin America. This study set out to validate this test among people attending the public test street in Sint Maarten, Dutch Caribbean.MethodsPeople of all ages were recruited from the public COVID-19 test street regardless of COVID-19 symptoms. They received a nasopharyngeal swab for the Abbott Panbio COVID-19 RAT and the RT-PCR Qtower. Diagnostic accuracy of the RAT was compared to the RT-PCR among the overall study population and for subgroups with/without symptoms, with/without close contact and different Ct values.ResultsUsing a RT-PCR Ct cut-off value of <33, 119 out of 1,411 people (8.4%) tested positive for SARS-CoV-2. Most were asymptomatic (59%). The overall sensitivity and specificity of the RAT was 84% (95% CI 76.2-90.1) and 99.9% (95% CI 99.6-100) respectively. The sensitivity reduced to 67.6% (95% CI: 49.5%, 82.6%) among people without symptoms, regardless of whether they were in close contact with a known COVID-19 case. Sensitivity reduced considerably with a Ct cut-off value of <35.ConclusionsThe Abbott Panbio RAT is a valid and cheaper alternative to RT-PCR when used on symptomatic individuals among the general population. However, among asymptomatic people it should not be used as a stand-alone test and negative results should be confirmed with RT-PCR.

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Head-to-head performance comparison of self-collected nasal versus professional-collected nasopharyngeal swab for a WHO-listed SARS-CoV-2 antigen-detecting rapid diagnostic test

10.1101/2021.03.17.21253076 ◽

2021 ◽

Author(s):

Julian A.F. Klein ◽

Lisa J. Kr&uumlger ◽

Frank Tobian ◽

Mary Gaeddert ◽

Federica Lainati ◽

...

Keyword(s):

Scale Up ◽

High Viral Load ◽

Performance Comparison ◽

World Health ◽

Nasopharyngeal Swab ◽

Rapid Diagnostics ◽

Sample Collection ◽

Rt Pcr ◽

Percent Agreement ◽

Health Organization

Background: In 2020, the World Health Organization (WHO) recommended two SARS-CoV-2 lateral flow antigen detecting rapid diagnostics tests (Ag-RDTs), both initially with nasopharyngeal (NP) sample collection. Independent head-to-head studies demonstrated for SARS-CoV-2 Ag-RDTs nasal sampling to be a comparable and reliable alternative for nasopharyngeal (NP) sampling. Methods: We conducted a head-to-head comparison study of a supervised, self-collected nasal mid-turbinate (NMT) swab and a professional-collected NP swab, using the Panbio Ag-RDT (the second WHO-listed SARS-CoV-2 Ag-RDT, distributed by Abbott). We calculated positive and negative percent agreement and, compared to the reference standard reverse transcription polymerase chain reaction (RT-PCR), sensitivity and specificity for both sampling techniques. Results: A SARS-CoV-2 infection could be diagnosed by RT-PCR in 45 of 290 participants (15.5%). Comparing the NMT and NP sampling the positive percent agreement of the Ag-RDT was 88.1% (37/42 PCR positives detected; CI 75.0% - 94.8%). The negative percent agreement was 98.8% (245/248; CI 96.5% - 99.6%). The overall sensitivity of Panbio with NMT sampling was 84.4% (38/45; CI 71.2% - 92.3%) and 88.9% (40/45; CI 76.5% - 95.5%) with NP sampling. Specificity was 99.2% (243/245; CI 97.1% - 99.8%) for both, NP and NMT sampling. The sensitivity of the Panbio test in participants with high viral load (> 7 log10 SARS-CoV-2 RNA copies/mL) was 96.3% (CI 81.7% - 99.8%) for both, NMT and NP sampling. Conclusion: For the Panbio Ag-RDT supervised NMT self-sampling yields to results comparable to NP sampling. This suggests that nasal self-sampling could be used for scale-up population testing.

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SARS-CoV-2 in peritoneal swabs from asymptomatic patients undergoing emergency abdominal surgery

Journal of Surgical Case Reports ◽

10.1093/jscr/rjab116 ◽

2021 ◽

Vol 2021 (4) ◽

Author(s):

Jasim AlAradi ◽

Rawan A Rahman AlHarmi ◽

Mariam AlKooheji ◽

Sayed Ali Almahari ◽

Mohamed Abdulla Isa ◽

...

Keyword(s):

Peritoneal Fluid ◽

Case Series ◽

Rapid Test ◽

Nasopharyngeal Swab ◽

Rt Pcr ◽

Protective Measures ◽

The Public ◽

Asymptomatic Patients ◽

Number Of Patients ◽

Viral Transfer

Abstract This is a case series of five patients with acute abdomen requiring surgery who tested positive for coronavirus disease 2019 (COVID-19) and were asymptomatic, with the purpose of detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in peritoneal fluid. Nasopharyngeal swab was done as a prerequisite for admission or prior to admission as part of random testing. Two methods of viral testing were employed: Xpert® Xpress SARS-CoV-2 (rapid test) and real-time reverse transcription polymerase chain reaction (RT-PCR). Either or both tests were done, with the former performed for patients requiring surgery immediately. Surgery was performed within 24–36 h from admission. Peritoneal fluid swabs were obtained for the detection of SARS-CoV-2 using RT-PCR test. Swabs were immediately placed in viral transfer media and delivered to the public health laboratory in an ice bag. SARS-CoV-2 was not detected in peritoneal swabs. Due to the limited number of patients, further studies are required; yet, protective measures should still be taken by surgeons when dealing with COVID-19 cases.

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Clinical Evaluation of a New Antigen-Based COVID-19 Rapid Diagnostic Test from Symptomatic Patients

Diagnostics ◽

10.3390/diagnostics11122300 ◽

2021 ◽

Vol 11 (12) ◽

pp. 2300

Author(s):

Saiful Arefeen Sazed ◽

Mohammad Golam Kibria ◽

Mohammad Sharif Hossain ◽

Md Fahad Zamil ◽

Pranob Chandra Adhikary ◽

...

Keyword(s):

Gold Standard ◽

Clinical Performance ◽

Detection System ◽

Rapid Test ◽

Test Results ◽

Rt Pcr ◽

Test Procedures ◽

Healthcare Facilities ◽

The Right ◽

Current Detection

Accurate diagnosis at the right moment is the prerequisite for treatment of any disease. Failure to correctly diagnose a disease can result in highly detrimental effects, unmistakably a crucial factor during the COVID-19 pandemic. RT-PCR is the gold standard for COVID-19 detection while there are other test procedures available, such as LAMP, X-Ray, and ELISA. However, these tests are expensive, require sophisticated equipment and a highly trained workforce, and multiple hours or even days are often required to obtain the test results. A rapid and cheap detection system can thus render a solution to the screening system on a larger scale and be added as an aid to the current detection processes. Recently, some rapid antigen-based COVID-19 tests devices have been developed and commercialized. In this study, we evaluated the clinical performance of a new rapid detection device (OnSite® COVID-19 Ag Rapid Test by CTK Biotech Inc., Poway, CA, USA) on COVID-19 symptomatic patients (n = 380). The overall sensitivity and specificity were 91.0% (95% CI: 84.8–95.3%) and 99.2% (95% CI: 97.1–99.9), against gold standard RT-PCR. The kit was capable of detecting patients even after 06 days of onset of symptoms and the sensitivity can be maximized to 98% in samples with an average RT-PCR Ct ≤ 26.48, demonstrating a high potential of the kit for clinical diagnosis of symptomatic patients in healthcare facilities.

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Direct Comparison of SARS Co-V-2 Nasal RT- PCR and Rapid Antigen Test (BinaxNOWTM) at a Community Testing Site During an Omicron Surge

10.1101/2022.01.08.22268954 ◽

2022 ◽

Author(s):

John Schrom ◽

Carina Marquez ◽

Genay Pilarowski ◽

Grace Wang ◽

Anthea Mitchell ◽

...

Keyword(s):

San Francisco ◽

High Viral Load ◽

Antigen Test ◽

Rt Pcr ◽

Repeat Testing ◽

Single Antigen ◽

Testing Site ◽

Antigen Testing ◽

Test Result ◽

Community Site

In 731 persons seeking COVID-19 testing at a walk-up San Francisco community site in January 2022, simultaneous nasal rapid antigen testing (BinaxNOWTM) and RT-PCR testing was performed. There were 296 (40.5%) positive tests by RT-PCR; 97% of a random sample were the omicron variant. Sensitivity of a single antigen test was 95.2% (95% CI 92-98%); 82.1% (95% CI 77-87%) and 65.2% (95% CI 60-70%) for Ct threshold of < 30, < 35 and no threshold, respectively. A single BinaxNowTM rapid antigen test detected 95% of high viral load omicron cases from nasal specimens. As currently recommended, repeat testing should be done for high- risk persons with an initial negative antigen test result.

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Clinical performance of the point-of-care cobas Liat for detection of SARS-CoV-2 in 20 minutes: A multicenter study

Journal of Clinical Microbiology ◽

10.1128/jcm.02811-20 ◽

2020 ◽

Author(s):

Glen Hansen ◽

Jamie Marino ◽

Zi-Xuan Wang ◽

Kathleen G. Beavis ◽

John Rodrigo ◽

...

Keyword(s):

Influenza A ◽

Clinical Performance ◽

Point Of Care ◽

Nasopharyngeal Swab ◽

Molecular Testing ◽

Rt Pcr ◽

Percent Agreement ◽

Individual Care ◽

Pcr Technology ◽

Acid Test

Background: Highly accurate testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the point of care (POC) is an unmet diagnostic need in emergency care and time-sensitive outpatient care settings. Reverse transcription-polymerase chain reaction (RT-PCR) technology is the gold-standard for SARS-CoV-2 diagnostics. Methods: We performed a multi-site United States (US) study comparing the clinical performance of the first US Food and Drug Administration (FDA) authorized POC RT-PCR test for detection of SARS-CoV-2 in 20 minutes, the cobas® Liat SARS-CoV-2 & Influenza A/B nucleic acid test, to the most widely used RT-PCR laboratory test, the cobas® 68/8800 SARS-CoV-2 test. Results: Clinical nasopharyngeal swab specimens from 444 patients with 357 evaluable specimens at five US clinical laboratories were enrolled from September 21, 2020 to October 23, 2020. The overall agreement between the Liat and 68/8800 systems for SARS-CoV-2 diagnostics was 98.6% (352/357). Using Liat, positive percent agreement for SARS-CoV-2 was 100% (162/162) and the negative percent agreement was 97.4% (190/195). Conclusion: The Liat is an RT-PCR POC test that provides highly accurate SARS-CoV-2 results in 20 minutes with equivalent performance to high-throughput laboratory molecular testing. Rapid RT-PCR testing at the POC can enable more timely infection control and individual care decisions for Coronavirus Disease 2019.

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