CCL20 and infection: In an earlier study of the gill transcriptome of salmon presmolts infected with SGPV during a natural outbreak of SGPVD (7), we could not observe any obvious recruitment of T-cells to gills after infection, and observed an early suppression of transcript markers of innate T-cell recruitment and activity, including interleukin (IL)-22, the chemokine CCL20 and T-cell receptor (TCR) Fcγ (7, 13).