Volume 26, Number 8—August 2020
Synopsis
US CDC Real-Time Reverse Transcription PCR Panel for Detection of Severe Acute Respiratory Syndrome Coronavirus 2
Table 5
Reproducibility of the US CDC rRT-PCR panel for detection of SARS-CoV-2 with respiratory specimen matrix spiked with SARS-CoV-2*
Virus titer, TCID50 | N1 Ct |
N2 Ct |
N3 Ct |
RP Ct |
|||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Test 1 | Test 2 | Test 3 | Test 1 | Test 2 | Test 3 | Test 1 | Test 2 | Test 3 | Test 1 | Test 2 | Test 3 | ||||
Day 1 | |||||||||||||||
1.0 × 103 | 21.1 | 21.1 | 21.0 | 21.5 | 21.2 | 21.5 | 21.0 | 21.1 | 21.1 | 26.0 | 25.9 | 26.1 | |||
1.0 × 101 | 27.8 | 27.6 | 27.5 | 28.6 | 28.6 | 28.9 | 27.6 | 27.3 | 27.7 | 26.0 | 25.8 | 26.1 | |||
1.0 × 10−1 |
35.6 |
33.8 |
33.8 |
34.7 |
34.2 |
34.5 |
34.0 |
34.5 |
33.7 |
26.4 |
26.4 |
26.4 |
|||
Day 2 | |||||||||||||||
1.0 × 103 | 21.8 | 21.8 | 21.8 | 21.6 | 21.5 | 21.6 | 21.2 | 21.1 | 21.2 | 26.5 | 26.3 | 26.3 | |||
1.0 × 101 | 28.4 | 28.3 | 28.5 | 29.4 | 29.3 | 29.0 | 28.1 | 28.0 | 28.1 | 26.7 | 26.7 | 26.67 | |||
1.0 × 10−1 |
37.6 |
35.7 |
34.0 |
36.0 |
34.7 |
34.9 |
34.1 |
33.8 |
34.5 |
26.8 |
26.3 |
26.2 |
|||
Day 3 | |||||||||||||||
1.0 × 103 | 20.8 | 20.7 | 20.8 | 20.6 | 20.4 | 20.6 | 20.7 | 20.6 | 20.7 | 26.8 | 26.7 | 26.9 | |||
1.0 × 101 | 27.1 | 27.6 | 27.3 | 27.5 | 27.6 | 27.4 | 27.2 | 27.3 | 27.3 | 26.6 | 26.8 | 26.8 | |||
1.0 × 10−1 |
34.2 |
33.9 |
34.1 |
33.1 |
33.5 |
34.9 |
33.2 |
34.2 |
33.5 |
26.6 |
26.9 |
26.7 |
|||
Summary results | Mean | SD | CV | Mean | SD | CV | Mean | SD | CV | Mean | SD | CV | |||
1.0 × 103 | 21.2 | 0.5 | 2.2% | 21.2 | 0.5 | 2.3% | 21.0 | 0.2 | 1.1% | 26.4 | 0.4 | 1.4% | |||
1.0 × 101 | 27.8 | 0.5 | 1.8% | 28.5 | 0.8 | 2.8% | 27.6 | 0.4 | 1.3% | 26.5 | 0.4 | 1.5% | |||
1.0 × 10−1 | 34.7 | 1.3 | 3.7% | 34.5 | 0.8 | 2.5% | 33.9 | 0.4 | 1.2% | 26.5 | 0.2 | 0.9% |
*Specimen matrix constructed from combined nasopharyngeal swabs obtained from 10 persons. CDC, Centers for Disease Control and Prevention; Ct, cycle threshold; neg, negative; CV, coefficient of variation; N, nucleocapsid protein gene; RP, ribonuclease P gene; rRT-PCR, real-time reverse transcription PCR; SARS-CoV-2, severe acute respiratory coronavirus 2; TCID50, 50% tissue culture infectious dose.
†50% tissue culture infectious dose/mL.