FIG 3.

Limits of detection of the singleplex or multiplex qPCR to detect either the Chinese or the Japanese strain of SFTSV. Isolated strains HB29, YG1, and SPL005 were diluted with serum as described in Fig. 1, and purified RNA was amplified. The singleplex (A to C) or multiplex (D to F) qPCR copy numbers at each dilution of HB29 (A and D), YG1 (B and E), or SPL005 (C and F) that were detected by NP (square), GPC (triangle), or RdRp (diamond) are shown as dots and lines. The theoretical copy number of each strain estimated by undiluted viruses whose viral titers (TCID₅₀/ml) were known are shown in orange.