Fig. 1.

Dilutions and thermal lysis mimic RNA extraction values. 60 known positive samples in UTM (n = 30) and in RNase-free water (n = 30) were divided in 3 equal groups and analysed in 3 independent experiments by rRT-PCR on E, RdRP and N viral genes. Undiluted extracted samples were used as reference values. Red numbers indicate the percentage of detected samples. a, b samples were directly used without any dilution, with or without thermal lysis treatment. c–f Samples were diluted in 1/2 and 1/5; with or without thermal lysis treatment