Tapeworm infection - Vejthani Hospital | JCI Accredited International Hospital in Bangkok, Thailand.

Tapeworm infection

Overview

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.

Symptoms

Signs and symptoms will depend on the location of the tapeworm infection:

  • Tapeworm infection in the intestines: There could be no indications of an intestinal tapeworm. The quantity of tapeworms affects the severity of symptoms and they may vary. Additionally, certain tapeworm species are more prone to exhibit particular symptoms. Possible symptoms include:
    • Diarrhea.
    • Gas.
    • Hunger.
    • Hungry for foods high in salt.
    • Loose stools.
    • Loss of appetite.
    • Stomach pain.
    • Stomach upset, or nausea
    • Weight loss.
  • Larval cyst infection: The location in the body where larval cyst infections are producing disease determines the symptoms.
    • Brain or spine:
      • Changes in behaviors.
      • Dizziness.
      • Headache.
      • Muscle weakness.
      • Nerve pain in the spine or limbs.
      • Poor balance.
      • Seizures.
    • Other organs: These may have an effect on the organ’s performance. Larval cysts, for instance, can result in serious illness of the heart, lungs, or liver. The variety of symptoms is extensive. There may occasionally be a palpable bump. The location of the larval cyst infection may also be painful and swollen.

They may seek medical attention if an individual experience any of the signs and symptoms for tapeworm infection.

Causes

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:

  • Pork tapeworms: Humans can serve as either the definitive or intermediate host. Consuming undercooked pork can lead to an infection with adult pork tapeworms, with eggs excreted in feces potentially leading to another individual or the same individual contracting a larval cyst infection due to poor hygiene practices.
  • Dwarf tapeworm: Humans ingest the dwarf tapeworm as eggs, which can come from contaminated food or water, or due to inadequate hand hygiene. The eggs hatch in the intestines, with the larvae embedding in the intestinal wall to form cysts that develop into adult tapeworms. Some eggs are expelled in the stool, while others hatch within the intestine, perpetuating the infection cycle.

Risk factors

Having a tapeworm or larval cyst infection could be caused by the following factors:

  • Consuming raw or undercooked meats: Eating raw or undercooked meat and fish is a major risk factor for acquiring tapeworm infection. Fish that has been dried and smoked may also have larval cysts.
  • High-risk location: One of the risk factors is living in or visiting areas with high infection rates.
  • Insufficient clean water: Exposure to tapeworm eggs is increased when there is insufficient clean water available for drinking, bathing, and food preparation.
  • Poor hygiene: The likelihood of getting and spreading diseases is increased by improper hand washing. Moreover, unwashed vegetables can harbor tapeworm eggs.
  • Poor sanitation and sewage: Livestock is more likely to come into contact with human tapeworm eggs when there is inadequate sanitation and sewerage for human waste. This increases the possibility of contaminated meat being consumed.