Oh hun I don't know When you talk to him does he understand? Does he just sort of nod or do you think he understands when you explain about the germs?

Maybe tell him to come and see you everytime he has poo on his hands and every time he does he gets a star in a star chart or something? And then when he gets x amount of stars he gets a prize?? That way you are praising him for doing the right thing not the other way around iykwim??

It must be really hard for you...is it something that can be fixed? Poor little bugger