FWIW - it isn't entirely wrong, the wiki says: "Ringworm is a disease caused by infection of the skin by fungus, appearing as scaly, ring-shaped patches." then

FWIW - it isn't entirely wrong, the wiki says: "Ringworm is a disease caused by infection of the skin by fungus, appearing as scaly, ring-shaped patches." then it goes on to describe it in Harry Potter But yeah should be looked at!