Cysticercosis (Pork Tapeworm, Taeniasis)
Taeniasis is an intestinal infection with the adult stage of large tapeworms; cysticercosis is a tissue infection with the larval stage of the pork tapeworm, Taenia solium. Other Taenia species can occasionally cause cysticercosis as well. People get pork tapeworm from eating raw or undercooked infected pork. Infected pork may look “measly” because it has larval cysts in the muscle. The larval cysts develop into adult tapeworms in the person’s intestine and produce a large number of eggs. Eggs are passed in the stool and are then spread through food, water, or surfaces contaminated with feces. People develop cysticercosis by swallowing these eggs. The eggs hatch in the small intestine and larvae migrate to various tissues throughout the body, where they form cysts. This is called cysticercosis. If the cysts are in the brain, the condition is called neurocysticercosis.
Tapeworms are found worldwide; however, infection is more common in countries where pigs roam freely and eat human feces. Infection can occur even if you have never traveled outside the United States. Infections with adult tapeworms are often unnoticed. Occasionally a person may have nervousness, anorexia, weight loss, and abdominal pain. Symptoms of cysticercosis can be severe, depending on where the cysts form in the body. Persons infected with adult tapeworms will have eggs in their stool 8 to 12 weeks after initial infection. The adult tapeworm can live in the intestine and produce eggs for more than 30 years. Symptoms of cysticercosis may appear from weeks to ten years or more after infection, often when the larval cysts are dying. Anti-parasitic and anti-inflammatory drugs are most often used. Surgery is necessary for certain types of cysticercosis, but some infections may not require treatment.
How can I prevent pork tapeworm infection?
Prevent infection by never eating raw or undercooked pork and other meats. Always wash your hands with soap and water after using the toilet and before handling food, especially when traveling in developing countries.