We have recently shown that hMPV infection of airway epithelial cells induces the expression RIG-I and MDA-5 and that RIG-I, but not MDA-5, plays a fundamental role in hMPV-induced cellular signaling, as inhibition of RIG-I expression significantly decreases activation of IRF and NF-кB transcription factors and production of type I IFN and proinflammatory cytokines and chemokines [17]. Here, IFIH1 is linked to infection.