cysticercus

biology

Also known as: bladder worm

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Last updated

June 25, 2026

Quick Summary

A cysticercus is the larval stage of a tapeworm, specifically a tapeworm larva that consists of a fluid-filled sac containing an invaginated scolex (head). This stage is found within the tissues of an intermediate host. The term "bladder worm" is also used to describe this larval tapeworm.12

Tapeworms are parasitic flatworms that can affect various animals, including humans. Their life cycles are often complex, involving intermediate hosts where larval stages develop. For example, the pork tapeworm (Taenia solium) can form a cysticercus in the muscle tissue of an intermediate host. If this cysticercus is ingested by a definitive host, it develops into an adult tapeworm. Diseases caused by tapeworms are known as cestodiasis. Echinococcosis is a disease caused by the larval stage of Echinococcus tapeworms, forming cysts in organs like the liver and lungs.345

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tapeworm
…(encysts) and is called a cysticercus, or bladder worm. If the cysticercus is eaten alive in raw meat, it attaches itself to the host’s intestine and develops directly into a mature adult.
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…(encysts) and is called a cysticercus, or bladder worm. If the cysticercus is eaten alive in raw meat, it attaches itself to the host’s intestine and develops directly into a mature adult.
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myositis
…is the pork tapeworm larva, Cysticercus, which causes nodules in the muscle tissue and brain. The organism grows, lays its eggs, and then dies. The nodes become calcified and may be seen on X rays.
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…is the pork tapeworm larva, Cysticercus, which causes nodules in the muscle tissue and brain. The organism grows, lays its eggs, and then dies. The nodes become calcified and may be seen on X rays.
Read More