CDC publish instructions for use of RT-PCR test

On January 24, 2020 the CDC provided information for laboratories and  publish their instructions for use of Real-Time RT-PCR Panel for Detection 2019-Novel Coronavirus  along with publishing initial PCR “Primers and Probes” sequences [1, 2, 3, 4]

The charts indicated amplifying cycles up to 45, but stated Under Interpreting Test Results tht “RP should be positive at or before 35 cycles for all clinical samples and HSC, thus indicating the presence of sufficient nucleic acid from human RNase P gene and that the specimen is of acceptable quality.”  Their graph indicated the Cycle Threshold (Ct) before the “exponential PCR phase” was between 22 to 28 cycles of amplification.