Before bite-sized crustaceans like crayfish, shrimp and prawns land on our dinner plates, they first have to get fat themselves—and it turns out they relish the freshwater snails that transmit the parasite that causes schistosomiasis, the second most devastating parasitic disease worldwide, after malaria.
source https://www.lifetechnology.com/blogs/life-technology-news-blog/how-fat-prawns-can-save-lives