IRF7 and viral infectious disease: Viral infection recognized by innate immune systems triggers two signaling cascades: (a) stimulating the production of pro-inflammatory cytokine (e.g., IL1, IL6, TNF) through NFkB1-mediated pathway; (b) stimulating the production of type I and type III IFNs through interferon regulatory factor (IRF3 and IRF7) mediated pathways (45).