ACTB and infection: As shown in Figure 5c, expression of the β-actin gene was detected in all of the samples, but none of the genes’ expression (ICP18, dUTPase, and MCP, which are representative genes of different transcription stages of RGV and ADRV, and N for SMRV) can be detected in different time points after infection, indicating the three viruses cannot be replicated in BHK-21 cells at 37 °C.