CD40LG and infection: In general, acute C. shasta infections with the virulent genotypes GIIR in steelhead and chinook salmon (Hurst et al., 2019; Barrett and Bartholomew, 2021) or GI in chinook salmon (Bjork et al., 2014) induce igm and igt expression, although susceptible ALLO fish were not able to resolve infection or parasite proliferation and the inflammatory process continued.