Establishment and evaluation of a quadruple quantitative real-time PCR assay for simultaneous detection of human coronavirus subtypes

Table 2 Interpretation criteria for the results of the qq-PCR assay

Ct value				Result
FAM channel	ROX channel	Cy5 channel	VIC channel	Result
≥ 38.5/undetermined/no Ct	≥ 38.5/undetermined/no Ct	≥ 38.5/undetermined/no Ct	≤ 38.5	Negative
≤ 38.5	≤ 38.5	≥ 38.5/undetermined/no Ct	≤ 38.5	SARS-CoV-2
≥ 38.5/undetermined/no Ct	≤ 38.5	≥ 38.5/undetermined/no Ct	≤ 38.5	Severe HCoVs (SARS-CoV-2 or SARS-CoV)
≥ 38.5/undetermined/no Ct	≥ 38.5/undetermined/no Ct	≤ 38.5	≤ 38.5	Seasonal HCoVs

Ct, cycle threshold; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; HCoVs, human coronavirus; SARS-CoV, severe acute respiratory syndrome coronavirus

ISSN: 1743-422X