The transcription level of IRF-7 continued to decrease after infection, and we hypothesized that the transcription of IRF-7 might be inhibited by TIBOV, eventually reducing the production of IFNs. However, the significant increase of the transcriptional levels of IL-6 was detected in the early stage of TIBOV infection (2, 4, and 6 dpi). This evidence concerns the gene IL6 and infection.