A hemagglutinin-esterase-expressing salmonid alphavirus replicon protects Atlantic salmon (Salmo salar) against infectious salmon anemia (ISA)

► A replicon vaccine protected against infectious salmon anemia virus challenge. ► The replicon induced an innate immune response locally at the site of vaccination. ► The ISAV HE induced protection, but neither the F nor the M protein were essential. ► The replicon offers new perspectives for the development of viral fish vaccines.