Assigning variants with CT>36 RTPCR010
Generally, if any of the Ct values for the virus targets (FAM, HEX or Texas/ROX) is above 36, the result should not be considered for lineage assignment. If the N target is in the range of >36 Ct <40 the results should be “SARS CoV2 POSITIVE, LINEAGE NOT DETERMINED”.
Below Ct 36 results should be considered for lineage assignment either by the Vircom result interpretation software or manual interpretation but not above Ct 36.
The reason for setting this threshold is that above Ct 36 the lineage assignment is not precise as the amount of RNA in the sample is very low, and the lineage could not be confirmed by sequencing due to scarce RNA.
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In attached files.
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