A tapeworm is a type of parasitic organism that resides and feeds within the intestines of various animals, including humans, as well as livestock, cats, and dogs, typically those that consume meat. As parasites, mature tapeworms depend on living inside a host from which they draw nutrients. They attach their heads to the interior lining of the host’s intestines, absorbing nutrients from the food being digested. Tapeworms have a juvenile, inactive stage known as a larval cyst, which can survive in different body parts, leading to a condition known as larval cyst infection.
Typically, a tapeworm presence in the intestines induces only mild symptoms, but more severe symptoms such as abdominal discomfort and diarrhea can emerge. Significantly, when larval cysts embed in critical bodily regions like the brain, liver, lungs, heart, or eyes, they can trigger serious health complications. To combat tapeworm infections, anti-parasitic drugs are employed. Treatments for larval cyst infections may include the use of anti-parasitic medications as well as surgical removal of cysts. Other medications may be administered to alleviate symptoms.
Signs and symptoms will depend on the location of the tapeworm infection:
They may seek medical attention if an individual experience any of the signs and symptoms for tapeworm infection.
Most tapeworm species require two distinct hosts to complete their life cycle: an intermediate host, where the parasite transitions from egg to larva, and a definitive host, where the larva matures into an adult. For instance, the lifecycle of the beef tapeworm involves both cattle and humans. The eggs of the beef tapeworm can endure in the environment for extensive periods. When a cow, serving as the intermediate host, consumes vegetation contaminated with these eggs, they hatch within the cow’s intestines. The larvae then enter the bloodstream, migrating to the muscle tissues where they encase themselves within cysts. Humans become the definitive host when they ingest undercooked beef containing these larval cysts, leading to tapeworm infection. Inside the human intestine, the cysts release adult tapeworms that attach to the intestinal lining to feed and reproduce, eventually releasing eggs that are excreted in feces. Tapeworm infections in humans can occur through the consumption of raw or undercooked meats such as beef, pork, or fish. In some cases, humans can also act as intermediate hosts for certain tapeworm species. This typically occurs through the ingestion of food or water contaminated with tapeworm eggs, including exposure to eggs found in canine feces. The ingested eggs hatch in the intestines, with the larvae then dispersing via the bloodstream to form cysts in various body tissues. These larval cysts, which do not develop into adult tapeworms in humans, can lead to symptoms years after initial infection, often triggered by the immune system’s response to the cysts.
Notably, there are exceptions to the typical tapeworm life cycle in humans:
Having a tapeworm or larval cyst infection could be caused by the following factors: