Table 2.
Confirmation of Analytical Sensitivity of Quidel SARS Antigen FIA test on Sofia 2 analyzer using clinical specimens. Clinical specimens in PBS transport media were spiked onto swabs for antigen test, resulting in a calculated theoretical CT value of how much virus was used as input for the antigen test.
| UW Sample ID | Original Roche cobas CT | Original Copies / mL | Copies / swab | Theoretical Roche cobas CT | Quidel SOFIA 2 Antigen Detection |
|---|---|---|---|---|---|
| PBS 21 | 14.24 | 2.67E+09 | 1.34E+08 | 19.6 | Positive |
| PBS 10 | 14.49 | 2.20E+09 | 1.10E+08 | 19.9 | Positive |
| PBS 2 | 15.12 | 1.36E+09 | 6.80E+07 | 20.5 | Positive |
| PBS 7 | 17.23 | 2.69E+08 | 1.35E+07 | 22.6 | Positive |
| PBS 33 | 17.41 | 2.34E+08 | 1.17E+07 | 22.8 | Positive |
| PBS 35 | 19.18 | 6.02E+07 | 3.01E+06 | 24.5 | Positive |
| PBS 32 | 19.19 | 5.98E+07 | 2.99E+06 | 24.5 | Positive |
| PBS 29 | 19.35 | 5.28E+07 | 2.64E+06 | 24.7 | Positive |
| PBS 38 | 19.8 | 3.74E+07 | 1.87E+06 | 25.2 | Positive |
| PBS 55 | 20.38 | 2.40E+07 | 1.20E+06 | 25.7 | Positive |
| PBS 15 | 20.5 | 2.19E+07 | 1.09E+06 | 25.8 | Positive |
| PBS 37 | 20.52 | 2.15E+07 | 1.08E+06 | 25.9 | Positive |
| PBS 53 | 21.01 | 1.48E+07 | 7.39E+05 | 26.4 | Positive |
| PBS 14 | 21.29 | 1.19E+07 | 5.96E+05 | 26.6 | Positive |
| PBS 45 | 21.3 | 1.18E+07 | 5.91E+05 | 26.6 | Positive |
| PBS 19 | 21.56 | 9.69E+06 | 4.84E+05 | 26.9 | Positive |
| PBS 52 | 21.58 | 9.54E+06 | 4.77E+05 | 26.9 | Positive |
| PBS 22 | 21.63 | 9.18E+06 | 4.59E+05 | 27.0 | Positive |
| PBS 26 | 22.52 | 4.64E+06 | 2.32E+05 | 27.9 | Positive |
| PBS 36 | 22.63 | 4.26E+06 | 2.13E+05 | 28.0 | Negative |
| PBS 34 | 22.66 | 4.16E+06 | 2.08E+05 | 28.0 | Positive |
| PBS 51 | 23.23 | 2.69E+06 | 1.34E+05 | 28.6 | Positive |
| PBS 25 | 24.22 | 1.26E+06 | 6.28E+04 | 29.6 | Positive |
| PBS 47 | 24.48 | 1.03E+06 | 5.15E+04 | 29.8 | Negative |
| PBS 27 | 25.56 | 4.49E+05 | 2.25E+04 | 30.9 | Positive |
| PBS 57 | 26.33 | 2.49E+05 | 1.24E+04 | 31.7 | Negative |
| PBS 28 | 26.35 | 2.45E+05 | 1.23E+04 | 31.7 | Positive |
| PBS 9 | 27.61 | 9.31E+04 | 4.66E+03 | 32.9 | Positive |
| PBS 12 | 28.13 | 6.25E+04 | 3.12E+03 | 33.5 | Negative |
| PBS 43 | 28.56 | 4.49E+04 | 2.25E+03 | 33.9 | Negative |
| PBS 23 | 29.14 | 2.88E+04 | 1.44E+03 | 34.5 | Negative |
| PBS 58 | 29.15 | 2.86E+04 | 1.43E+03 | 34.5 | Negative |
| PBS 30 | 29.3 | 2.54E+04 | 1.27E+03 | 34.6 | Negative |
| PBS 50 | 29.36 | 2.43E+04 | 1.22E+03 | 34.7 | Negative |
| PBS 8 | 29.61 | 2.01E+04 | 1.00E+03 | 34.9 | Negative |
| PBS 1 | 30.21 | 1.27E+04 | 6.33E+02 | 35.5 | Negative |
| PBS 11 | 30.26 | 1.22E+04 | 6.09E+02 | 35.6 | Negative |
| PBS 41 | 30.53 | 9.90E+03 | 4.95E+02 | 35.8 | Negative |
| PBS 31 | 30.79 | 8.11E+03 | 4.05E+02 | 36.1 | Negative |
| PBS 3 | 30.83 | 7.86E+03 | 3.93E+02 | 36.1 | Negative |
| PBS 16 | 31.43 | 4.96E+03 | 2.48E+02 | 36.7 | Negative |
| PBS 48 | 31.74 | 3.91E+03 | 1.95E+02 | 37.1 | Negative |
| PBS 18 | 31.82 | 3.68E+03 | 1.84E+02 | 37.1 | Negative |
| PBS 44 | 31.87 | 3.54E+03 | 1.77E+02 | 37.2 | Negative |
| PBS 5 | 32.55 | 2.10E+03 | 1.05E+02 | 37.9 | Negative |
| PBS 46 | 32.67 | 1.91E+03 | 9.57E+01 | 38.0 | Negative |
| PBS 17 | 32.79 | 1.75E+03 | 8.73E+01 | 38.1 | Negative |
| PBS 42 | 33.2 | 1.27E+03 | 6.37E+01 | 38.5 | Negative |
| PBS 54 | 33.2 | 1.27E+03 | 6.37E+01 | 38.5 | Negative |
| PBS 49 | 33.58 | 9.52E+02 | 4.76E+01 | 38.9 | Negative |
| PBS 39 | 33.66 | 8.95E+02 | 4.48E+01 | 39.0 | Negative |
| PBS 40 | 33.97 | 7.06E+02 | 3.53E+01 | 39.3 | Negative |
| PBS 24 | 34.02 | 6.79E+02 | 3.40E+01 | 39.3 | Negative |
| PBS 56 | 34.14 | 6.19E+02 | 3.10E+01 | 39.4 | Negative |
| PBS 13 | 34.21 | 5.87E+02 | 2.93E+01 | 39.5 | Negative |
| PBS 4 | 36 | 1.49E+02 | 7.43E+00 | 41.3 | Negative |
| PBS 20 | 37.73 | 3.94E+01 | 1.97E+00 | 43.0 | Negative |
| PBS 6 | 37.97 | 3.27E+01 | 1.64E+00 | 43.3 | Negative |