The largest tapeworms can reach an amazing size, measuring more than 45 feet long in some cases. The adult beef tapeworm is usually 15 to 30 feet long (4.5 t0 9 meters). An infected person usually has only one or two worms. The tapeworms use their head, called the scolex, to attach themselves to the intestinal wall. They have 1,000 to 2,000 body segments, called proglottids, cach containing 80,000 to 100,000 eggs. The eggs can survive for months or years in the environment outside the human body. If humans eat raw or undercooked beef containing cysts, the cysts develop over a two-month period into adult tapeworms. Adult beef tapeworms can live for more than 30 years.
The adult pork tapeworm is about half as long as the beef tapeworm, usually eight to 11 feet (2.5 to 3.5 meters) long. It also has a scolex for attaching to the intestinal wall and a body of about 1,000 proglottids. Each proglottid contains about 50,000 eggs. Adult pork tapeworms can live up to 25 years.
The adult fish tapeworm is from 3 to 49 feet long (one to 15 meters) and is the longest human tapeworm. They have 3,000 to 4,000 proglottids that are wider than they are long, giving this tapeworm the name broad tapeworm. The fish tapeworm affects freshwater fish as well as some salt-water fish that have a freshwater component to their lifecycle (such as salmon). Fish tapeworm infestations are most common in societies that consume large amounts of raw or pickled fish.
How Is Tapeworm Infestation Diagnosed and Treated?
Eggs and proglottids can be seen in stool samples by microscopic examination. In order to differentiate between a beef, pork, or fish tapeworm, a scolex has to be removed and examined. This is seldom done, as doctors usually can prescribe the same medication for all types of tapeworm infestation. Stool is checked at three and six months after treatment to ensure that the parasite is gone.
Cysticercosis is diagnosed by examining the muscles or brain with а CT scan, which uses x-rays and computers to view structures inside the body that contain cysts. Blood tests for antibodies, which are specific proteins the body makes to fight the tapeworm infestation, can confirm the diagnosis. Tapeworm infestations are treated with one of various types of anti-worm drug called anthelmintics (ant-HEL-min-tics). Some anthelmintics work only in the gastrointestinal tract while others affect body tissues. Cysticercosis can be treated with some types of anthelmintics, but in rare instances cysts may be removed surgically.
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