IFIH1 and infection: Thus, while RIG-I is activated during infection with flaviviruses, paramyxoviruses, influenza, and others, MDA5 is responsible for detection of picornaviruses (Gitlin et al., 2006; Kato et al., 2006; Pichlmair et al., 2009; Wang et al., 2010; Feng et al., 2012).