• 17Jul

    Tapeworms in humans -what are the symptoms?

    Tapeworms are flat and long worms that look like a tape. Along their length they are made of multiple segments. They can be found in the intestine of grazing animals. Human infection occurs due to consumption of uncooked meat of these animals. Human tapeworm infections are caused by a variety of tapeworms. Usually infection with these parasites is asymptomatic, but sometimes depending on the site or organ mainly involved, symptoms may occur.

    Types of tapeworms in human

    • Taenia saginata (beef tapeworm): This is the largest tapeworm and can as long as 10 meters.
    • Taenia solium (pork tapeworm)
    • Taenia asiatica (Asian tapeworm)
    • Diphyllobothrium latum (fish tapeworm)
    • Echinococcus granulosus (dog or sheep tapeworm)  

    Mode of human infection

    Tapeworm eggs are ingested during consumption of water, food or soil contaminated with feces. Sewage farming which uses sewage water along sewerage for faster production of vegetables has a great contribution towards spread of these diseases. Tapeworm eggs are also transmitted by the contaminated hands of a food handler, chef or waiter. After ingestion these eggs hatch in the intestine where larvae are released. These larvae migrate to other organs like lungs, liver or brain and form cysts. In the intestine these larvae mature to adult tapeworms which may live up to 20 years. Invasion of other organs is seen in ‘cysticercosis’ caused by pork tapeworm and ‘echinococcosis’ (hydatid cyst) caused by dog or sheep tapeworm.

    Human infection also occurs by eating raw or undercooked beef in case of T. saginata or pork in patients with T. solium and T. asiatica. Diphyllobothrium latum comes from eating fish.

    Vitamin B12 deficiency is a prominent feature of fish tapeworm infection.

    Vitamin B12 deficiency is a prominent feature of fish tapeworm infection.

    What are the symptoms of tapeworm infection?

    Majority of people with tapeworm infection are asymptomatic or have mild symptoms. Since these worms are found in the intestine, they cause abdominal symptoms like loss of appetite, abdominal cramps, bloating, weight loss, anemia and indigestion. Pork tapeworm can cause dimness of vision or seizures due to cyst formation in the eyes or brain. Presence of segments of these worms in digestive tract may cause bile duct stones, obstructive jaundice, appendicitis and pancreatitis. Malabsorption of food resulting in vitamin and mineral deficiency also occurs. Vitamin B12 deficiency is a prominent feature of fish tapeworm infection. In the presence of cysts in brain, intracranial pressure may increase.


    • Tapeworm segments may be noticed in feces. Hence, diagnosis of a particular type of worm may require stool examination under a microscope.
    • Serological tests are done to detect the antibodies against a particular parasite.
    • Imaging by computed tomography (CT) or magnetic resonance imaging (MRI) can detect cysts.


    A physician consult is essential to diagnose the type of tapeworm infection. Appropriate steps are taken based on the diagnosis.

    Oral medications: These include praziquantel, albendazole and niclosamide. These drugs are not absorbed in the intestine but act locally and kill the intestinal tapeworms. The dead worms are passed in stools. Since these drugs do not kill the eggs, hygiene should be maintained even during this treatment. Stool tests are done for one to three months after completion of medical therapy to ensure complete elimination of tapeworm infection.

    Surgery: In the presence of hydatid cyst in organs like liver or lungs, surgery is performed especially in case of pressure effects.

     Prevention of tapeworm infection

    • Well cooked meat should be consumed as heat is a good method of destruction of tapeworm eggs and cysts.
    • Hand hygiene is essential. Wash your hand with soap and water before consuming food and after using a toilet.
    • Vegetables and fruits should be washed with clean water.

    Tapeworms are a big family of parasites which affect us. Their presence is associated with lack of hygiene or incorrect eating habits. Adequate precautions should be taken to prevent a spectrum of disorders. An improvement in the quality of life and basic hygiene are essential for prevention of such diseases.

    Anna L.

    It’s all about health!
    I have academic background in drugs related Chemical Technology, as well as extensive professional experience in pharma and medical companies. My main area of interest is everyday life medicine. The goal of my articles is to give people informative answers to the questions that bother them, to dispel doubts and some common misbeliefs and also to inspire everyone to keep healthy lifestyle.

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