Fig. 1

SFTSV replicates in brain tissue. A Weight changes of newborn mice after infection with SFTSV (n = 4 to 6). B Changes of viral loads in brain tissues of newborn mice infected with SFTSV (n = 4 to 6). qRT-PCR was used to detect the viral loads in brain tissues of newborn mice, and the SFTSV nucleic acid was detected at 3 hpi. The viral loads of the 3 h group were set as the benchmark, while the log2 fold changes of the other groups and the 3 h group were calculated. C Indirect immunofluorescence (IFA) detected the infectious virus particles in the brain tissues. Newborn mice were sacrificed at 3 hpi, 2 day post-infection (dpi), and 7 dpi, respectively. The brain tissues were homogenized, and the infectious SFTSV particles were detected by IFA. SFTSV was probed by SFTSV nucleoprotein (NP) human mAb and a FITC-conjugated goat anti-human IgG (H + L) secondary antibody (green); nuclei were stained with DAPI (blue). Bar = 50 μm