A tapeworm is a parasite that can live and feed in human intestines. This is called a tapeworm infection.
A young and inactive form of the tapeworm is called a larval cyst. It can stay alive in other parts of the body. This is called a larval cyst infection.
A tapeworm in the intestines often causes mild symptoms. Moderate to severe symptoms may include stomach pain and diarrhea. Larval cysts can cause serious disease if they are in a person's brain, liver, lungs, heart or eyes.
Tapeworm infections are treated with anti-parasitic drugs. Treatments for larval cyst infections may include anti-parasitic drugs and surgery to remove the cyst. Other drugs may be used to treat symptoms.
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Symptoms depend mostly on where the infection happens in the body.
Tapeworm infection in the intestines
A tapeworm in the intestines may cause no symptoms. The severity of symptoms depends in part on the number of tapeworms. Symptoms vary. And some symptoms are more likely with some species of tapeworm. Symptoms may include:
- Upset stomach, or feeling like you could throw up.
- Stomachache or stomach pain.
- Not wanting to eat.
- Loose stools.
- Weight loss.
- Hunger pains.
- Cravings for salty food.
Larval cyst infection
Symptoms of larval cyst infection depend on where they are causing disease in the body.
- Larval cysts in the brain or spine.These may cause:
- Nerve pain in the spine or limbs.
- Muscle weakness.
- Poor coordination.
- Changes in thinking or behaviors.
- Larval cysts in other organs.These can affect how well the organ works. For example, larval cysts can cause severe disease in the liver, lungs or heart. Symptoms vary widely. In some cases, a lump can be felt. There also may be pain and swelling at the site of the larval cyst infection.
When to see a doctor
If you experience any of the symptoms of tapeworm or larval cyst infection, get medical care.
Request an appointment
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Most tapeworms need two different hosts to complete a life cycle. One host is the place where a parasite grows from egg to larva, called the intermediate host. The other host is where the larva become adults, called the definitive host. For example, beef tapeworms need cattle and humans to go through a complete life cycle.
The beef tapeworm eggs can survive in the environment for months or years. If a cow, the intermediate host, eats grass with these eggs on it, the eggs hatch in its intestines. The young parasite, called a larva, passes into the bloodstream and moves to muscles. It forms a protective shell, called a cyst.
When people, the definitive host, eat undercooked meat from that cow, they can develop a tapeworm infection. The larval cyst develops into an adult tapeworm. The tapeworm attaches to the wall of the intestine where it feeds. It produces eggs that pass in the person's stool.
In this case, the cow is called the intermediate host, and the person is the definitive host.
Humans are the definitive hosts for some species of tapeworms. They may get a tapeworm infection after eating raw or undercooked:
Larval cyst infections
Humans may be the intermediate hosts for other tapeworm species. This usually happens when they drink water or eat food with tapeworm eggs. Humans also can be exposed to eggs in dog feces.
An egg hatches in the person's intestines. The larva travels through the bloodstream and forms a cyst somewhere in the body.
The larval cyst matures. But it won't become a tapeworm. Cysts vary by species. Some cysts have a single larva. Others have several larvae. Or they can make more. If a cyst bursts, it can lead to cysts forming in other parts of the body.
Symptoms usually show up years after the infection began. They happen when the immune system responds to the cyst shedding debris, breaking down or hardening. Symptoms also appear when one or more cysts keep an organ from working correctly.
There are two exceptions to the typical life cycle of tapeworms that can infect humans.
- Pork tapeworms.Humans can be a definitive host or an intermediate host for pork tapeworms. For example, a person can have adult pork tapeworms from eating undercooked pork. The eggs pass in the person's stool. Poor handwashing may lead to the same person or another person being exposed to the eggs. If this happens, a person can get a larval cyst infection.
- Dwarf tapeworm.The dwarf tapeworm enters humans as eggs from food or water. Exposure also may happen because of poor handwashing. The egg hatches in the intestines. The larva burrows into the wall of the intestines and forms a larval cyst. This becomes an adult dwarf tapeworm. Some eggs from the tapeworm pass in stool. Other eggs hatch in the intestine to make a repeating cycle.
Factors that may put you at greater risk of tapeworm or larval cyst infection include:
- Eating raw or undercooked meats.The main risk factor for tapeworm infection is eating raw or undercooked meat and fish. Dried and smoked fish also may have larval cysts in them.
- Poor hygiene.Poor handwashing increases the risk of getting and spreading infections. Unwashed fruits and vegetables also can carry tapeworm eggs.
- Lack of sanitation and sewage.Lack of sanitation and sewage for human waste increases the risk of livestock getting tapeworm eggs from people. This increases the risk of people eating infected meat.
- Lack of clean water.A lack of clean water for drinking, bathing and making food increases the risk of exposure to tapeworm eggs.
- High-risk regions.Living in or traveling to regions with high rates of infection is a risk factor.
From tapeworm infections
Tapeworm infections usually don't cause complications. Problems that may happen include:
- Anemia.Long-term infection with a fish tapeworm may lead to the body not making enough healthy red blood cells, also called anemia. This can happen because the tapeworm keeps the body from getting enough vitamin B-12.
- Blockages.In some cases, a part of a tapeworm can block a duct that connects another organ to the intestines.
- Anxiety.People may be anxious or stressed about having a tapeworm infection, seeing parts of tapeworms in stool or passing long tapeworms.
- Severe allergic reaction.Larval cysts may shed debris or break down. When the immune system reacts, it may cause symptoms of severe allergy. Symptoms may include difficulty breathing, fainting, fever and a drop in blood pressure.
From larval cyst infections
Complications from larval cysts vary depending on what organ is affected. Serious complications include the following.
- Larval cysts in the brain or central nervous system.These can cause:
- Inflammation, or swelling, of the fluids and membranes surrounding the brain and spinal column, also called meningitis.
- Buildup of fluid in the brain, also called hydrocephalus.
- Pressure on the spinal cord.
- Damage to nerves, blood vessels or the brainstem.
- Larval cysts in other organs.These can lead to:
- Cyst growth that damages organ tissue.
- Bacterial disease in cysts.
- Bacterial disease related to blockages caused by cysts.
These steps can help prevent infections with tapeworms or tapeworm larval cysts.
- Wash your hands.Wash your hands with soap and water for at least 20 seconds. This is very important after using the toilet, before eating, and before and after handling food.
- Wash fruits and vegetables.Rinse fruits and vegetables under running water before eating, peeling or preparing them.
- Wash kitchen utensils well.Wash cutting boards, knives and other utensils with soapy water after contact with raw meats or unwashed fruits and vegetables.
- Don't eat raw or undercooked meat or fish.Use a meat thermometer to make sure meat is cooked enough to kill larval cysts. Cook whole meats and fish to at least 145 degrees Fahrenheit (63 degrees Celsius) and let rest for at least three minutes. Cook ground meat to at least 160 degrees Fahrenheit (71 degrees Celsius).
- Freeze meat.Freezing meat and fish can kill larval cysts. Freeze at minus 4 degrees Fahrenheit (minus 20 degrees Celsius) or below for 7 days.
- Treat infected dogs.Treat dogs with tapeworms right away.
By Mayo Clinic Staff
Jan. 05, 2023
Eating raw or undercooked meats.
The main risk factor for tapeworm infection is eating raw or undercooked meat and fish. Dried and smoked fish also may have larval cysts in them.
A tapeworm infection is usually diagnosed by finding eggs or tapeworm segments in the stool. Your doctor may ask you to bring in a sample so a lab can look for eggs, larvae, or tapeworm segments. A blood test can spot antigens, foreign substances that let your doctor know your body is trying to fight the infection.What happens if tapeworms go untreated in humans? ›
If your doctor confirms you have a tapeworm infection, follow their instructions to lessen the risk of complications. If left untreated, there's the risk of developing an invasive infection which can affect your tissue and organs. This can lead to brain swelling, inflammation, and intestinal blockage.How long can you have a tapeworm without knowing? ›
Many times, people can be infected for long periods of time without even knowing they have a tapeworm infection. While viral or bacterial infections can disappear in a matter of days or weeks, a tapeworm could be with you for years.What kills tapeworms in humans? ›
You can easily kill tapeworms with anthelmintic drugs, including praziquantel (Biltricide®), albendazole (Albenza®) and nitazoxanide (Alinia®). Healthcare providers usually recommend praziquantel because it also paralyzes the worm, forcing it to dislodge from your intestinal wall.Will tapeworm infection go away? ›
Anyone who has a tapeworm will need medical treatment to get rid of it. Treatment is about 95% effective and typically takes a few days.Do you still poop if you have a tapeworm? ›
Once inside the body, the tapeworm head attaches to the inner wall of the intestines and feeds off the food being digested. Pieces of the tapeworm break off and come out of the body in feces (poop), along with the eggs they contain.How do you get rid of tapeworms naturally? ›
Eat more raw garlic, pumpkin seeds, pomegranates, beets, and carrots, all of which have been used traditionally to kill parasites. In one study, researchers found that a mixture of honey and papaya seeds cleared stools of parasites in 23 out of 30 subjects. Drink a lot of water to help flush out your system.What does a tapeworm do to the human body? ›
Tapeworms can cause digestive problems including abdominal pain, loss of appetite, weight loss, and upset stomach. The most visible sign of taeniasis is the active passing of proglottids (tapeworm segments) through the anus and in the feces.How long can a person live with a tapeworm? ›
Left untreated, adult tapeworms can live in a host body for up to 30 years. Their length varies, but they can grow to be anywhere from 6 to 22 feet.
This diet may include avoiding greasy, processed foods and eating natural, whole foods. Some parasite cleansing diets ask the person to avoid specific types of foods, such as gluten, dairy, or pork. Diets may also include the use of anti-inflammatory herbs and spices, such as garlic, turmeric, and ginger.How do you test for tapeworms in humans? ›
Diagnosis of Taenia tapeworm infections is made by examination of stool samples; individuals should also be asked if they have passed tapeworm segments. Stool specimens should be collected on three different days and examined in the lab for Taenia eggs using a microscope.Can you feel a tapeworm moving in your stomach? ›
Although adult tapeworms in the intestine usually cause no symptoms, some people experience upper abdominal discomfort, diarrhea, and other symptoms. Occasionally, people with a tapeworm can feel a piece of the worm move out through the anus or see part of the ribbon-like tapeworm in stool.What foods fight tapeworms? ›
Eat more raw garlic, pumpkin seeds, pomegranates, beets, and carrots, all of which have been used traditionally to kill parasites. In one study, researchers found that a mixture of honey and papaya seeds cleared stools of parasites in 23 out of 30 subjects. Drink a lot of water to help flush out your system.What are the signs that you need to deworm? ›
- abdominal pain.
- diarrhea, nausea, or vomiting.
- gas and bloating.
- unexplained weight loss.
- abdominal pain or tenderness.
Tapeworms can be contagious for humans and other pets. Humans rarely contract dipylidium caninum, as it requires ingesting fleas, but this parasite can spread to other household dogs through the intermediate flea host. Cats can contract some species of tapeworms, like taenia species.How do you flush out tapeworms? ›
Tapeworms are usually treated with a medicine taken by mouth. The most commonly used medicine for tapeworms is praziquantel (Biltricide). These medications paralyze the tapeworms, which let go of the intestine, dissolve, and pass from your body with bowel movements.What are the stages of tapeworm infections? ›
All cestodes cycle through 3 stages—eggs, larvae, and adults. Adults inhabit the intestines of definitive, or final, hosts, which are mammalian carnivores, including humans.How long do tapeworms last untreated? ›
Tapeworms can live up to two years if untreated, but often do not cause great harm to their host. These worms can grow up to 20 inches long, however, they are usually smaller.What is the long string in my poop? ›
Rope worms are long structures that sometimes occur in the intestines. They are likely a buildup of intestinal mucus and debris and may pass in a person's stool during an enema or other clearing procedure. Some researchers claim that rope worms are parasites, while others believe them to be intestinal debris.
Use an anthelmintic medication (aka a medicine used to destroy worms). Some anthelmintic medicines, like mebendazole, thiabendazole, and albendazole, starve and kill the worms. Other medicines, like ivermectin and praziquantel, paralyze the worms so they pass in your stool.How does a tapeworm make you feel? ›
Taeniasis can cause mild and non-specific symptoms, including abdominal pain, nausea, diarrhoea or constipation when the tapeworms become fully developed in the intestine.What does a tapeworm look like from a human? ›
Threadworms look like tiny pieces of white cotton. Roundworms look more like earthworms. Hookworms can cause a red worm-shaped rash. Tapeworms are long, pale yellow and flat.How do you know if you have a parasite in your stomach? ›
Common parasite symptoms may include: Diarrhea. Nausea and vomiting. Abdominal pain.Are tapeworms life threatening? ›
This is serious and potentially fatal. Infection with tapeworm eggs causes cysts to form in vital organs such as the liver and lungs.Can doctors tell if you have a tapeworm? ›
Diagnosis of tapeworm infection
A health care provider tests for a tapeworm infection in the intestines using a test of a stool sample. A lab test may find pieces of tapeworms or eggs. You may give a sample on more than one day.
Symptoms may include diarrhoea, tiredness and weakness, abdominal pain and weight loss. Some worms cause anaemia.How long does it take for tapeworms to show in humans? ›
Humans become infected by eating raw or undercooked infected beef or pork. Once ingested, cysticerci attach to the small intestine and develop into adult tapeworms over the course of 2 months.How is tapeworm disease transmitted? ›
You can be infected with tapeworm larvae by eating raw or undercooked meat, such as beef, pork, or fish. You can consume tapeworm eggs in infected water or by accidentally coming into contact with dog faeces, for example by handling an object, food or water that has been contaminated.How common is tapeworm infection? ›
Tapeworm infections are rare in the United States. When they do happen, they're easy to treat. Often, people may not know they have a tapeworm infection because they have no symptoms or their symptoms are mild.
By swallowing a flea infected with a tapeworm larvae. A dog or cat may swallow a flea while self-grooming. Once the flea is digested by the dog or cat, the larval tapeworm is able to develop into an adult tapeworm.Where are tapeworm infections most common? ›
Both the tapeworm infection, also known as taeniasis, and cysticercosis occur globally. The highest rates of infection are found in areas of Latin America, Asia, and Africa that have poor sanitation and free-ranging pigs that have access to human feces.How long can a tapeworm get inside a person? ›
Left untreated, adult tapeworms can live in a host body for up to 30 years.What does a tapeworm look like when passed? ›
Tapeworms or tapeworm segments may be visible in the stool when they are passed along with a bowel movement. 2 In particular, a head-like part of the tapeworm that has suckers and hook-like structures that attach to the intestine, called a scolex, may be seen.Who is most at risk for tapeworm? ›
People who live in close proximity to livestock or free-range animals and/or have poor sanitation have a greater risk of developing a tapeworm infection. Tapeworm infections are more common in developing areas of the world where sanitation is poor and people may eat undercooked meats.How common are tapeworm infections in the US? ›
There are few data on the prevalence of taeniasis, or adult tapeworm infection, in the United States. However, persons with taeniasis are the source of autochthonous transmission of cysticercosis. The two published population-based studies of taeniasis suggest that the prevalence may be 0.5–3% in select populations.How fast does tapeworm spread? ›
Humans become infected by eating raw or undercooked infected beef or pork. Once ingested, cysticerci attach to the small intestine and develop into adult tapeworms over the course of 2 months. The adult tapeworms produce proglottids that mature, detach, and migrate to the anus and are then passed in the feces.Are tapeworms contagious to people? ›
The most common tapeworm is called Dipylidium caninum. These are easy-to-treat tapeworms in cats, and they are not contagious to humans. Dipylidium is something veterinarians see every day.Are tapeworms highly contagious? ›
Tapeworms can be contagious for humans and other pets. Humans rarely contract dipylidium caninum, as it requires ingesting fleas, but this parasite can spread to other household dogs through the intermediate flea host. Cats can contract some species of tapeworms, like taenia species.What is the most common way to get a tapeworm? ›
Tapeworms have a three-stage lifecycle: egg, an immature stage called a larva, and an adult stage at which the worm can produce more eggs. Because larvae can get into the muscles of their hosts, infection can occur when you eat raw or undercooked meat from an infected animal.