Figure 3.
RT-PCR results of respiratory samples with low positivity, SARS-CoV-2 detection, Germany, March 2020 (n = 28 samples)
CDC: Centers for Disease Control and Prevention; Cp: crossing point; E: envelope gene; N: nucleocapsid gene; RdRp: RNA-dependent RNA-polymerase gene; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2.
Nucleic acid eluates of clinical respiratory specimens that initially showed low positive results in the CDC N1 reaction (Cp value > 35) were retested side by side in the CDC N1, the Charité E and original RdRp reaction and using the modified RdRp primers on the Roche LightCycler 480 using the QuantiNova Multiplex RT-PCR kit. Cp values are shown with positive amplifications beyond cycle 40 shown as > 40 (dotted line).
