Regarding the real PAMPs in infections by RNA viruses, the cb and id types of DI genomes were identified as the ligands of RIG-I in SeV- and IAV-infected cells, respectively, both of which could form ideal structures as the RIG-I ligands (Baum et al., 2010; Baum and Garcia-Sastre, 2011; Martinez-Gil et al., 2013). The gene discussed is ID1; the disease is infection.