Fusion of flagellin 2 with bivalent white spot syndrome virus vaccine increases survival in freshwater shrimp

•Here, baculovirus-based WSSV vaccine fused with Salmonella typhimurium flagellin 2 (FL2) was constructed.•Oral administration of Macrobrachium nipponense with the resulting vaccine (Ac-VP28-ie1VP19FL2) efficiently protected against WSSV challenge, and FL2-fused WSSV envelope gene effectively induced protective responses.