IRF7 and coinfection: The results regarding an earlier modulatory effect observed during PDCoV/PEDV co-infection as compared with single-PDCoV or -PEDV infection suggest that viral co-infection induced the TRAF6-mediated canonical NF-κB and IRF7 signaling pathways, adding to the potential synergistic effects that result in enhanced PDCoV replication during PEDV co-infection18,44.