At 96 h after infection, the transcription levels of immune-related factors such as OASL, Mx, and IFN-α in the FadV-4 GY single-infected (group A) and co-infected groups (group G) were maintained at high levels, while the above factors were not significantly upregulated in the aHEV-YT single-infected group (group B). This evidence concerns the gene IFNA1 and infection.