TABLE 4.
Additional Stability of SARS-CoV-2 RNA in Saline detected by the Quest EUA and Roche cobas EUAa
| Specimen condition | Platform | Detectorb | Mean CT (SD) of 3 specimens on day: |
||||||
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 5 | 7 | 14 | |||
| Room temp (18 to 26°C) | Quest | N1 | 26.2 (0.1) | 26.3 (0.0) | 26.1 (0.5) | 26.8 (0.1) | 27.2 (0.1) | 26.4 (0.1) | 26.8 (0.4) |
| N3 | 30.2 (0.1) | 30.3 (0.1) | 30.0 (0.4) | 30.7 (0.1) | 31.5 (0.1) | 29.3 (0.1) | 29.3 (0.3) | ||
| cobas | ORF1a/b | 27.9 (0.3) | 28.4 (0.2) | 28.5 (0.1) | 29.1 (0.1) | 29.4 (0.2) | 29.5 (0.0) | 30.0 (0.2)c | |
| E gene | 28.1 (0.3) | 28.6 (0.2) | 28.7 (0.1) | 29.3 (0.2) | 29.7 (0.2) | 29.9 (0.2) | 30.4 (0.2)c | ||
| Refrigerated (2 to 8°C) | Quest | N1 | 26.2 (0.1) | 26.4 (0.1) | 26.0 (0.2) | 26.5 (0.0) | 27.0 (0.1) | 26.3 (0.2) | 26.5 (0.2) |
| N3 | 30.2 (0.1) | 30.2 (0.1) | 29.8 (0.2) | 30.6 (0.0) | 31.3 (0.1) | 29.0 (0.2) | 29.1 (0.1) | ||
| cobas | ORF1a/b | 27.9 (0.3) | 28.5 (0.1) | 28.5 (0.1) | 28.8 (0.1) | 29.2 (0.1) | 29.3 (0.1) | 29.9 (0.1) | |
| E gene | 28.1 (0.3) | 28.8 (0.1) | 28.7 (0.1) | 29.1 (0.1) | 29.5 (0.1) | 29.5 (0.2) | 30.2 (0.2)c | ||
| Frozen (−60 to −90°C) | Quest | N1 | 26.2 (0.1) | 26.3 (0.0) | 26.1 (0.5) | 26.8 (0.1) | 27.2 (0.1) | 26.4 (0.1) | 26.8 (0.4) |
| N3 | 30.2 (0.1) | 30.3 (0.1) | 30.0 (0.4) | 30.7 (0.1) | 31.5 (0.1) | 29.3 (0.1) | 29.3 (0.3) | ||
| cobas | ORF1a/b | 27.9 (0.3) | 28.4 (0.1) | 28.2 (0.2) | 28.7 (0.2) | 28.5 (0.2) | 28.3 (0.1) | 28.4 (0.1) | |
| E gene | 28.1 (0.3) | 28.7 (0.2) | 28.4 (0.3) | 28.7 (0.1) | 28.8 (0.1) | 28.6 (0.1) | 28.7 (0.0) | ||
a
Testing was performed at Quest Diagnostics, Marlborough, MA. Three replicates were assayed by rRT-PCR at each of the indicated conditions.
b
N1 and N3 TaqMan probes were as described in the Quest Diagnostics EUA package insert, and ORF1a and ORF1b (ORF1a/b) and E gene probes were as described in the Roche Diagnostics EUA package insert.
c
Increase of >2 CTs from day 0.