Head-to-Head Comparison of Nasopharyngeal, Oropharyngeal and Nasal Swabs for SARS-CoV-2 Molecular Testing

Larsen, Kasper Daugaard; Jensen, Mads Mose; Homøe, Anne-Sophie; Arndal, Elisabeth; Samuelsen, Grethe Badsberg; Koch, Anders; Nielsen, Xiaohui Chen; Homøe, Preben; Todsen, Tobias

doi:10.3390/diagnostics13020283

Cited by 4 publications

(4 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The nasal swab was inserted about 4 cm in both nostrils or until resistance was met and rotated 3 times (eAppendix 2 in Supplement 2). The throat swab collected a specimen from the posterior oropharyngeal wall and palatine tonsils, avoiding the tongue and cheeks . The throat and nose swabs were placed in separate inactivation transport media (Wuxi NEST Biotechnology Co, Ltd) and stored at 4 °C until transported to the laboratory for separate RT-PCR testing (reference standard).…”

Section: Methodsmentioning

confidence: 99%

“…The throat swab collected a specimen from the posterior oropharyngeal wall and palatine tonsils, avoiding the tongue and cheeks. 14,15 The throat and nose swabs were placed in separate inactivation transport media (Wuxi NEST Biotechnology Co, Ltd) and stored at 4 °C until transported to the laboratory for separate RT-PCR testing (reference standard). The RT-PCR analyses were performed at the Technical University of Denmark (DTU), Lyngby, or at the Department of Clinical Microbiology, Rigshospitalet (eAppendix 3 in Supplement 2).…”

Section: Molecular and Rapid Antigen Testing For Sars-cov-2mentioning

confidence: 99%

See 1 more Smart Citation

COVID-19 Rapid Antigen Tests With Self-Collected vs Health Care Worker–Collected Nasal and Throat Swab Specimens

Todsen,

Jakobsen,

Grønlund

et al. 2023

JAMA Netw Open

Self Cite

View full text Add to dashboard Cite

ImportanceSelf- or health care worker (HCW)–collected nasal swab specimens are the preferred sampling method to perform rapid antigen testing for COVID-19, but it is debated whether throat specimens can improve test sensitivity.ObjectiveTo compare the diagnostic accuracy of self- and HCW-collected nasal vs throat swab specimens for COVID-19 rapid antigen testing.Design, Setting, and ParticipantsThis per-protocol multicenter randomized clinical trial was conducted from February 15 through March 25, 2022. The participants, individuals aged 16 years or older requesting a COVID-19 test for diagnostic or screening purposes, had 4 specimens collected for individual testing at 1 of 2 urban COVID-19 outpatient test centers in Copenhagen, Denmark.InterventionsParticipants were randomized 1:1 to self-collected or HCW-collected nasal and throat swab specimens for rapid antigen testing. Additional HCW-collected nasal and throat swab specimens for reverse transcriptase–polymerase chain reaction (RT-PCR) were used as the reference standard.Main Outcomes and MeasuresThe primary outcome was sensitivity to diagnose COVID-19 of a self- vs HCW-collected nasal and throat specimen for rapid antigen testing compared with RT-PCR.ResultsOf 2941 participants enrolled, 2674 (90.9%) had complete test results and were included in the final analysis (1535 [57.4%] women; median age, 40 years [IQR, 28-55 years]); 1074 (40.2%) had COVID-19 symptoms, and 827 (30.9%) were positive for SARS-CoV-2 by RT-PCR. Health care worker–collected throat specimens had higher mean sensitivity than HCW-collected nasal specimens for rapid antigen testing (69.4% [95% CI, 65.1%-73.6%] vs 60.0% [95% CI, 55.4%-64.5%]). However, a subgroup analysis of symptomatic participants found that self-collected nasal specimens were more sensitive than self-collected throat specimens for rapid antigen testing (mean sensitivity, 71.5% [95% CI, 65.3%-77.6%] vs 58.0% [95% CI, 51.2%-64.7%]; P &lt; .001). Combining nasal and throat specimens increased sensitivity for HCW- and self-collected specimens by 21.4 and 15.5 percentage points, respectively, compared with a single nasal specimen (both P &lt; .001).Conclusions and RelevanceThis randomized clinical trial found that a single HCW-collected throat specimen had higher sensitivity for rapid antigen testing for SARS-CoV-2 than a nasal specimen. In contrast, the self-collected nasal specimens had higher sensitivity than throat specimens for symptomatic participants. Adding a throat specimen to the standard practice of collecting a single nasal specimen could improve sensitivity for rapid antigen testing in health care and home-based settings.Trial RegistrationClinicalTrials.gov Identifier: NCT05209178

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Molecular and Rapid Antigen Testing For Sars-cov-2mentioning

confidence: 99%

COVID-19 Rapid Antigen Tests With Self-Collected vs Health Care Worker–Collected Nasal and Throat Swab Specimens

Todsen,

Jakobsen,

Grønlund

et al. 2023

JAMA Netw Open

Self Cite

View full text Add to dashboard Cite

show abstract

“…Compared with the widely used RT-qPCR, MAG-CLIA offers cost reduction (1/3 of RT-qPCR costs) and enhanced e ciency (up to 600 tests in 60 min). Additionally, the standardized plasma sample collection process minimizes errors compared to nasopharyngeal swabs [32] and reduces discomfort associated with swabbing the nasal cavity [25]. However, our results indicate that plasma N protein may not be the optimal biomarker for assessing severe patients compared to other laboratory tests.…”

Section: Discussionmentioning

confidence: 92%

Plasma Nucleocapsid Protein: A Potential Beacon for COVID-19 Severity Prediction and Prognostic Insight in Severe Patients with Comorbidities

Wang,

Shen,

et al. 2024

Preprint

View full text Add to dashboard Cite

Objectives: The COVID-19 pandemic poses ongoing challenges to global public health systems, emphasizing the critical necessity for efficient diagnostic and prognostic markers. This study evaluates the MAGLUMI® SARS-CoV-2 Ag N protein chemiluminescent immunoassay (MAG-CLIA) for its analytical performance and its role in predicting disease severity and prognosis among severe COVID-19 patients with comorbidities. Methods: Analytical validation of plasma MAG-CLIA SARS-CoV-2 Ag N protein encompassed precision, interference, LoQ and linearity. Plasma N protein concentrations and other biomarkers were measured within 48 hours of admission, tracked until discharge or death. The Mann-Whitney U test explored the association between plasma N protein and COVID-19 severity or prognosis. Longitudinal monitoring of plasma N protein dynamics was conducted in representative patients. Results: MAG-CLIA demonstrated precise quantification of plasma N protein with a CV below 10% and minimal interference. The LoQ was 0.88 ng/L, with a broad linear range. Plasma N protein showed high diagnostic accuracy for COVID-19, achieving 95.42% sensitivity and 78.32% specificity at 2.388 ng/L. Plasma N protein emerged as a valuable prognostic indicator, correlating with mechanical ventilation need and patient survival. Plasma N protein concentrations ≥ 424.3 ng/L (AUC 0.8102, sensitivity 78.38%, specificity 85.48%) were associated with poor prognosis in severe COVID-19 patients with comorbidities. Conclusions: MAG-CLIA's SARS-CoV-2 N protein detection in plasma demonstrates both analytical reliability and clinical relevance in our inaugural evaluation. As a promising prognostic biomarker for severe COVID-19 patients, it offers crucial insights into disease severity and progression, emphasizing the significance of early monitoring and intervention, especially for patients with comorbidities.

show abstract

“…Many of the previous studies performing throat swabs also lack a detailed description of the sampling technique, which makes it difficult to compare the different diagnostic accuracy results. Some studies perform a throat swab by only collecting specimens from the posterior oropharyngeal wall [ 12 , 13 ], while others also include a swab of the palatine tonsils for SARS-CoV-2 testing [ 14 , 15 ]. However, recent studies suggest that throat swabs, including the palatine tonsils, have a higher sensitivity for SARS-CoV-2 detection than nasal and nasopharyngeal swabs in asymptomatic and early infectious stages [ 16 , 17 ].…”

Section: Introductionmentioning

confidence: 99%

Molecular Detection of SARS-CoV-2 From Throat Swabs Performed With or Without Specimen Collection From the Tonsils: Protocol for a Multicenter Randomized Controlled Trial

Hartvigsen,

Jakobsen,

Benfield

et al. 2024

JMIR Res Protoc

Self Cite

View full text Add to dashboard Cite

Background Testing for SARS-CoV-2 is essential to provide early COVID-19 treatment for people at high risk of severe illness and to limit the spread of infection in society. Proper upper respiratory specimen collection is the most critical step in the diagnosis of the SARS-CoV-2 virus in public settings, and throat swabs were the preferred specimens used for mass testing in many countries during the COVID-19 pandemic. However, there is still a discussion about whether throat swabs have a high enough sensitivity for SARS-CoV-2 diagnostic testing, as previous studies have reported a large variability in the sensitivity from 52% to 100%. Many previous studies exploring the diagnostic accuracy of throat swabs lack a detailed description of the sampling technique, which makes it difficult to compare the different diagnostic accuracy results. Some studies perform a throat swab by only collecting specimens from the posterior oropharyngeal wall, while others also include a swab of the palatine tonsils for SARS-CoV-2 testing. However, studies suggest that the palatine tonsils could have a tissue tropism for SARS-CoV-2 that may improve the SARS-CoV-2 detection during sampling. This may explain the variation of sensitivity reported, but no clinical studies have yet explored the differences in sensitivity and patient discomfort whether the palatine tonsils are included during the throat swab or not. Objective The objective of this study is to examine the sensitivity and patient discomfort of a throat swab including the palatine tonsils compared to only swabbing the posterior oropharyngeal wall in molecular testing for SARS-CoV-2. Methods We will conduct a randomized controlled study to compare the molecular detection rate of SARS-CoV-2 by a throat swab performed from the posterior oropharyngeal wall and the palatine tonsils (intervention group) or the posterior oropharyngeal wall only (control group). Participants will be randomized in a 1:1 ratio. All participants fill out a baseline questionnaire upon enrollment in the trial, examining their reason for being tested, symptoms, and previous tonsillectomy. A follow-up questionnaire will be sent to participants to explore the development of symptoms after testing. Results A total of 2315 participants were enrolled in this study between November 10, 2022, and December 22, 2022. The results from the follow-up questionnaire are expected to be completed at the beginning of 2024. Conclusions This randomized clinical trial will provide us with information about whether throat swabs including specimens from the palatine tonsils will improve the diagnostic sensitivity for SARS-CoV-2 molecular detection. These results can, therefore, be used to improve future testing recommendations and provide additional information about tissue tropism for SARS-CoV-2. Trial Registration ClinicalTrials.gov NCT05611203; https://clinicaltrials.g...

show abstract

Head-to-Head Comparison of Nasopharyngeal, Oropharyngeal and Nasal Swabs for SARS-CoV-2 Molecular Testing

Cited by 4 publications

References 23 publications

COVID-19 Rapid Antigen Tests With Self-Collected vs Health Care Worker–Collected Nasal and Throat Swab Specimens

COVID-19 Rapid Antigen Tests With Self-Collected vs Health Care Worker–Collected Nasal and Throat Swab Specimens

Plasma Nucleocapsid Protein: A Potential Beacon for COVID-19 Severity Prediction and Prognostic Insight in Severe Patients with Comorbidities

Molecular Detection of SARS-CoV-2 From Throat Swabs Performed With or Without Specimen Collection From the Tonsils: Protocol for a Multicenter Randomized Controlled Trial

Contact Info

Product

Resources

About