IRF3 and viral infectious disease: In response to viral infection, these RLRs associate with the mitochondrial antiviral signaling (MAVS) adaptor (also named IPS-1, Cardif and VISA) [2]–[5], leading to the activation of key transcriptional factors such as interferon regulatory factor 3 (IRF3) and nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-κB), induction of type I IFN, and ultimately production of hundreds of ISGs.