Diagnostic performance of a novel digital immunoassay (RapidTesta SARS-CoV-2): A prospective observational study with nasopharyngeal samples.
INTRODUCTION
Digital immunoassays are generally regarded as superior tests for the detection of infectious disease pathogens, but there have been insufficient data concerning SARS-CoV-2 immunoassays.


METHODS
We prospectively evaluated a novel digital immunoassay (RapidTesta SARS-CoV-2). Two nasopharyngeal samples were simultaneously collected for antigen tests and Real-time RT-PCR.


RESULTS
During the study period, 1127 nasopharyngeal samples (symptomatic patients: 802, asymptomatic patients: 325) were evaluated. For digital immunoassay antigen tests, the sensitivity was 78.3% (95% CI: 67.3%-87.1%) and the specificity was 97.6% (95% CI: 96.5%-98.5%). When technicians visually analyzed the antigen test results, the sensitivity was 71.6% (95% CI: 59.9%-81.5%) and the specificity was 99.2% (95% CI: 98.5%-99.7%). Among symptomatic patients, the sensitivity was 89.4% (95% CI; 76.9%-96.5%) with digital immunoassay antigen tests, and 85.1% (95% CI; 71.7%-93.8%) with visually analyzed the antigen test, respectively.


CONCLUSIONS
The sensitivity of digital immunoassay antigen tests was superior to that of visually analyzed antigen tests, but the rate of false-positive results increased with the introduction of a digital immunoassay device.
['Suzuki|Hiromichi|H|', 'Akashi|Yusaku|Y|', 'Ueda|Atsuo|A|', 'Kiyasu|Yoshihiko|Y|', 'Takeuchi|Yuto|Y|', 'Maehara|Yuta|Y|', 'Ochiai|Yasushi|Y|', 'Okuyama|Shinya|S|', 'Notake|Shigeyuki|S|', 'Nakamura|Koji|K|', 'Ishikawa|Hiroichi|H|']
D000956:Antigens, Viral D000086382:COVID-19 D006801:Humans D007118:Immunoassay D000086402:SARS-CoV-2 D012680:Sensitivity and Specificity
Digital immunoassay RapidTesta SARS-CoV-2 SARS-CoV-2 Nasopharyngeal sample Asymptomatic patients COVID-19