The virus infection pathways including human papillomavirus infection, Epstein-Barr virus infection, Hepatitis B, Kaposi sarcoma-associated herpesvirus infection, human immunodeficiency virus 1 infection, and immune-related pathways such as downstream signaling in naïve CD8+ T cells and signaling by interleukins were significantly enriched by these target genes (Figure 4(a)). Here, CD8A is linked to viral infectious disease.