A prospective evaluation of diagnostic performance of a combo rapid antigen test QuickNavi-Flu+COVID19 Ag
Journal of Infection and Chemotherapy, Available online 7 March 2022
https://www.sciencedirect.com/science/article/pii/S1341321X22000757
https://www.sciencedirect.com/science/article/pii/S1341321X22000757
鼻咽頭検体のリアルタイムRT-PCR（感染研法）を基準検査とし、鼻咽頭検体（1510検体）および鼻腔検体（862検体）を用いてクイックナビ-Flu+COVID19 Agの診断性能を前向きに評価。
クイックナビ-Flu+COVID19 Agはクイックナビ-COVID19 Ag（従来品）の15分から10分に診断時間を短縮。一つのキットでSARS-CoV-2とインフルエンザウイルスA/Bを同時に検査可能。
＜SARS-CoV-2＞
・鼻咽頭検体…感度80.9％、特異度99.8％
・鼻腔検体…感度67.8％、特異度100％
※鼻咽頭検体で抗原陽性・PCR陰性例が3件あったものの、1件は同日に追加した鼻咽頭検体でPCR陽性が確認され、初回のPCR陰性は検体採取不良が考えられた。
＜インフルエンザウイルス＞
・研究期間中にリアルタイムRT-PCRで検出例なし、クイックナビ-Flu+COVID19 Agでも陽性例なし
Abstract
Introduction
Since respiratory sample collection is an uncomfortable experience, simultaneous detection of pathogens with a single swab is preferable. We prospectively evaluated the clinical performance of a newly developed antigen test QuickNavi-Flu+COVID19 Ag (Denka Co., Ltd., Tokyo, Japan) which can detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses at the same time with a single testing device.
Methods
We included those who were suspected of contracting coronavirus disease 2019 (COVID-19) and were referred to a PCR center at Ibaraki prefecture in Japan, between August 2, 2021 to September 13, 2021, when the variant carrying L452R spike mutation of SARS-CoV-2 were prevalent. Additional nasopharyngeal samples and anterior nasal samples were obtained for the antigen test and were compared with a reference real-time reverse transcription PCR (RT-PCR) using nasopharyngeal samples.
We included those who were suspected of contracting coronavirus disease 2019 (COVID-19) and were referred to a PCR center at Ibaraki prefecture in Japan, between August 2, 2021 to September 13, 2021, when the variant carrying L452R spike mutation of SARS-CoV-2 were prevalent. Additional nasopharyngeal samples and anterior nasal samples were obtained for the antigen test and were compared with a reference real-time reverse transcription PCR (RT-PCR) using nasopharyngeal samples.
Results
In total, 1510 nasopharyngeal samples and 862 anterior nasal samples were evaluated. During the study period, influenza viruses were not detected by QuickNavi-Flu+COVID19 Ag and reference real-time RT-PCR. For SARS-CoV-2 detection in nasopharyngeal samples, the sensitivity and specificity of the antigen test were 80.9% and 99.8%, respectively. The sensitivity and specificity using anterior nasal samples were 67.8% and 100%, respectively. In symptomatic cases, the sensitivities increased to 88.3% with nasopharyngeal samples and 73.7% with anterior nasal samples. There were three cases of discrepant results between the antigen test and the real-time RT-PCR. All of them were positive with the antigen test but negative with the real-time RT-PCR in SARS-CoV-2 detection.
In total, 1510 nasopharyngeal samples and 862 anterior nasal samples were evaluated. During the study period, influenza viruses were not detected by QuickNavi-Flu+COVID19 Ag and reference real-time RT-PCR. For SARS-CoV-2 detection in nasopharyngeal samples, the sensitivity and specificity of the antigen test were 80.9% and 99.8%, respectively. The sensitivity and specificity using anterior nasal samples were 67.8% and 100%, respectively. In symptomatic cases, the sensitivities increased to 88.3% with nasopharyngeal samples and 73.7% with anterior nasal samples. There were three cases of discrepant results between the antigen test and the real-time RT-PCR. All of them were positive with the antigen test but negative with the real-time RT-PCR in SARS-CoV-2 detection.
Conclusion
A combo kit, QuickNavi-Flu+COVID19 Ag, showed an acceptable sensitivity and sufficient specificity for SARS-CoV-2 detection, especially using nasopharyngeal sample collected from symptomatic patients.
A combo kit, QuickNavi-Flu+COVID19 Ag, showed an acceptable sensitivity and sufficient specificity for SARS-CoV-2 detection, especially using nasopharyngeal sample collected from symptomatic patients.
