. 2021 Aug 16;134(17):2048–2053. doi: 10.1097/CM9.0000000000001687

Table 2.

SARS-CoV-2 rRT-PCR assays limits of detection (viral RNA copies/reaction).

	No. of positive tests/No. of test replicates (%)
Predicted No. of viral copies/reaction	ORF1ab	N	RdRp	N9
20	24/24 (100.0)	24/24 (100.0)	24/24 (100.0)	24/24 (100.0)
10	24/24 (100.0)	24/24 (100.0)^∗	24/24 (100.0)	24/24 (100.0)
5	24/24 (100.0)^∗	23/24 (95.8)	24/24 (100.0)^∗	24/24 (100.0)^∗
2.5	21/24 (87.5)	21/24 (87.5)	20/24 (83.3)	20/24 (83.3)
1.25	18/24 (75.0)	14/24 (58.3)	16/24 (66.7)	17/24 (70.8)

^∗

Limits of detection at which 100% of replicates were positive. ORF: Open reading frames; RdRp: RNA-dependent RNA polymerase; rRT-PCR: Real-time reverse transcription-polymerase chain reaction; SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2.