cestodë

Cestodes, commonly known as tapeworms, are parasitic flatworms belonging to the class Cestoda, subclass Eucestoda. They are endoparasites of vertebrates, meaning they live inside the bodies of animals, including humans. Cestodes are characterized by their elongated, flattened bodies, which are segmented into units called proglottids. They lack a digestive system, absorbing nutrients directly through their body surface from their host.

The life cycle of a cestode is typically complex, often involving one or more intermediate hosts before reaching the definitive host, where the adult worm resides and reproduces. The anterior end of a tapeworm is called the scolex, which is equipped with hooks or suckers used for attachment to the host's intestinal wall. Behind the scolex are the reproductive units, the proglottids. Each mature proglottid contains both male and female reproductive organs and can produce eggs.

Tapeworm infections in humans can result from consuming undercooked meat containing larval cysts, or through accidental ingestion of eggs found in contaminated food or water. Symptoms of infection vary depending on the tapeworm species and the location and number of worms in the host. Some infections are asymptomatic, while others can cause digestive upset, weight loss, and nutritional deficiencies. Diagnosis is usually made by identifying tapeworm eggs or proglottids in stool samples. Treatment typically involves antiparasitic medication.