Genes in SARS-CoV-2_hepatitis were related primarily to COVID-19, measles, human cytomegalovirus (HCV) infection, neurodegeneration multiple diseases, PD-L1 expression, and the PD-1 checkpoint pathway in cancer, legionellosis, cytokine-cytokine receptor interaction, antigen processing and presentation, and C-type lectin receptor pathway (Figure 3B). Here, CLEC4D is linked to COVID-19.