Table 2.
Sensitivity of rapid antigen tests for clinical specimens.
| RT-qPCR | Number of Samples a | Standard Q COVID-19 Ag | Espline SARS-CoV-2 | QuickNavi COVID19 Ag | ImmunoAce SARS-CoV-2 | Virus Isolation |
|---|---|---|---|---|---|---|
| (Cq Value) | ||||||
| –20.0 | 4 | 4 b | 4 | 3.5 | 3.5 | 2 c |
| 20.0–22.5 | 7 | 7 | 7 | 4.5 | 6 | 6 |
| 22.5–25.0 | 17 | 10.5 | 12.5 | 5 | 9.5 | 9 |
| 25.0–27.5 | 20 | 2.5 | 3 | 2 | 3.5 | 4 |
| 27.5–30.0 | 17 | 2 | 1 | 0 | 2 | 3 |
| 30.0– | 11 | 0 | 0 | 0 | 0 | 0 |
a A total of 76 clinical specimens including 7 gargle lavages, 27 saliva, 2 T swabs, 1 nasal vestibule swabs, 18 N swabs, 4 sputum, and 17 tracheal aspirates were examined. b Each sample was tested in two independent experiments; when a kit identified a sample as positive in both tests, a value of 1 was assigned. If only one test was positive, a value of 0.5 was assigned. If both tests were negative, a value of 0 was assigned. c Number of samples from which the virus was isolated.