If someone has a stomach bug, drinking water that is not sterile can add to the problems. I am thinking of the idea of finding pedialyte for a sick infant or child. My daughter drinks it when she has been gluten poisoned. Sterile water with hydrating additives can help a person who is vomiting and has diarrhea. This would be better than drinking water out of a stream, lake or pond if there is a stomach bug. In my genealogical research, I saw many infants and young children who died of something like a stomach bug. Would this be 100%? Probably not, but it could help.