Heterophyes heterophyes – Egg (25 µm X 15 µm) in stools

The egg of Heterophyes heterophyes is light brown, slightly asymmetrical with, sometimes, a rough scar at the abopercular end. H. heterophyes is the causative agent of an intestinal fluke disease. The operculum is not prominent. Man acquires the infection through the ingestion of undercooked fresh or brackish water fishes, that have muscles contaminated by encysted cercariae (2nd intermediate host).