Tapeworms are usually living in the hosts gut and they have three parts to their anatomy: a head (scolex), a neck and the segments (called “proglottids“, see arrows in image). The head has a suction device or a hook with which it attaches to the inside of the gut, typically in the small intestine.
There is one tapeworm, where the host is the dog and man becomes the intermediate host (target of tissue invasion by the larvae stage) and “hydatid cysts” are found in the liver and in the lungs. This is called hydatid disease. With the pork tapeworm the adult tapeworm can occur in the gut of man after eating raw meat with the storage form (called”cysticerci“) of Taenia solium. When eggs of T. solium are ingested, for instance from infestation of water, humans become intermediate hosts and the disease, called cysticercosis, can develop. The table above links you to a rundown of the common tapeworms.
Common Tapeworms (cestodes)
|Type of tapeworm:||Where is it in man?||Comments:|
|Beef tapeworm||small intestine||tapeworm lives for several years|
|Fish tapeworm||small intestine||from eating raw fish; may cause anemia from vitamin B-12 deficiency|
|Pork tapeworm||small intestine, from raw pork with cysticerci of T.solium||ingesting eggs of T.solium leads to man being intermediate host (cysticercosis, see text)|
|Hydatid and Alveolar hydatid disease||liver and other organs||after eggs are ingested from feces of infected dogs man becomes host|
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