The present disclosure relates to a composition for preventing, alleviating, or treating an inflammatory disease of the digestive system, particularly, colitis, comprising a reovirus or a variant thereof as an active ingredient.

Provided herein are diagnostics and vaccines to identify control and prevent novel porcine orthoreovirus type 3 (POV3) isolated from diarrheic feces of piglets from outbreaks in three states and ring-dried swine blood meal from multiple sources.