Definition
A bladder worm, also known as a cysticercus, is the larval stage of certain tapeworms (a type of platyhelminth). It consists of a fluid-filled bladder containing the scolex (head) of the future adult tapeworm. This larval stage typically resides in the tissues of an intermediate host. When the intermediate host is eaten by a definitive host, the bladder worm develops into an adult tapeworm. They can cause serious health problems in both animals and humans. Imagine it like a hidden package containing a parasitic surprise.