IFIH1 and viral infectious disease: For example, RIG-I seems to be essential for IFNs production in response to paramyxoviruses (244), influenza A virus (245) and Japanese encephalitis virus (246, 247), whereas MDA5 is critical for picornavirus detection (248) which is confirmed by high susceptibility of RIG-I-/- and MDA5-/- mice to these viral infections (249).