Life cycle of Fasciolopsis buski

Life cycle of Fasciolopsis buski
Photographer: Centers for Disease Control/Division of Parasitic Diseases and MalariaRights holder: Centers for Disease Control/Division of Parasitic Diseases and Malaria

Immature eggs are discharged into the intestine and stool. Eggs become embryonated in water and release miracidia, which invade a suitable snail intermediate host. In the snail, the parasites undergo several developmental stages: sporocyst, redia, and cercaria. The cercariae are released from the snail and encyst as metacercariae on aquatic plants. The mammalian hosts become infected by ingesting metacercariae on the aquatic plants. After ingestion, the metacercariae excyst in the duodenum and attach to the intestinal wall. There they develop into adult flukes (20 to 75 mm by 8 to 20 mm) in approximately 3 months, attached to the intestinal wall of the mammalian hosts (humans and pigs). The adults have a life span of about one year. (Centers for Disease Control Parasites and Health website)