White Spot Disease (WSD), caused by the White Spot Syndrome Virus (WSSV) is a threat to crustacean (e.g., shrimp & crawfish) farming in the US and globally. There is no measure to control WSD except prevention. RNA interference (RNAi)-based therapeutics delivered via injection to live shrimp has shown promise. However, due to the lack of an oral delivery method, there is no RNAi-based therapeutic for a commercial application, because injection of shrimp is not feasible.We propose to use a freshwater prawn, Macrobrachium rosenbergii Nodavirus (MrNV)-based viral vector to deliver RNAi molecules via oral route to control WSD.The objectives of the project are:Construction of a shrimp viral vector containing hairpin-RNA (hRNA) targeted against WSSV structural and non-structural genes. Confirm expression of hRNA molecules delivered using a shrimp viral vector in vitro (using Sf9 cells and shrimp primary hemocytes) and in vivo (live shrimp).Determine the efficacy of shrimp viral vector in delivering hRNA via diet and protecting shrimp against WSD.