In wild-type zebrafish, A. salmonicida infection repressed ifn3 but upregulated pro-inflammatory cytokines (il-8, il-1β, il-17, tnfα); GCRV-II infection induced ifn1, ifn3, il-8, and il-17; and co-infection upregulated ifn1, ifn3, il-8, and tnfα. Here, IL17A is linked to coinfection.