What Are the Symptoms of Tape Worms in Humans?

Adult tapeworms (Diplyidium caninum) live in the small intestines of various animals, including humans. They hook onto the small intestine walls with their rostellum and their six rows of teeth. They absorb the food and nutrients that pass through the small intestine during the normal digestive process. Tapeworms have a large growth range, from 1 mm to over 50 feet. Infection commonly occurs when people eat raw, undercooked, or infected beef, fish or pork.

Asymptomatic

When tapeworms attach to the intestinal walls, they typically cause a mild inflammation where they attach. Therefore, most people infected have no symptoms at all in the early stages of the infection and may never experience any symptoms. These people are usually aware of the infection only after finding tapeworm segments in their stool.

Digestive Symptoms

Some people may never really feel ill when they have a tapeworm, but they feel off or that something isn't "right," or they could have symptoms that can easily be dismissed as another digestive problem. These mild signs or symptoms include nausea, vomiting, weakness, loss of appetite, diarrhea, abdominal pain or cramping and weight loss. Like those with no symptoms, people with these vague symptoms may not conclude they have a tapeworm infection without the visual confirmation in their stool.

Cysticercosis

Occasionally, the larvae will move outside the intestines and form cysts in other areas of the body, which is an infection called cysticercosis. These cysts can cause tissue damage or more severe organ damage. Signs that this may have happened include fever, masses or lumps, bacterial infections, allergic reactions to the larvae and seizures or other neurological symptoms if the larvae migrate to the spinal cord or brain (neurocysticercosis).

Pernicious Anemia

Curiously, the tapeworm from freshwater fish rarely cause symptoms because they cause very little damage to the intestine when they attach. However, this tapeworm often absorbs a great amount of vitamin B12 from the intestine and causes a deficiency in the human host. The deficiency can lead to pernicious anemia, the inability to create new red blood cells due to the lack of B12.

Dwarf Tapeworm Symptoms

Dwarf tapeworms usually infect children since they can be passed from one human to another by the accidental ingestion of the eggs from feces. Symptoms from these tapeworms include nonlocalized abdominal pain, diarrhea with mucus and even bloody diarrhea.

Rodent Tapeworm Symptoms

Humans can contract rodent tapeworms by ingesting insects with the larvae, such as mealworms or grain beetles. This is another asymptomatic infection, but occasionally people have experienced headaches, anorexia, nausea and diarrhea.