Stories of tapeworm infection often conjure up images of 30-foot long worms loitering in a person's small intestine, only to make an appearance one day in the toilet bowl.
While this may describe the rare case, the common reality is very different. Infected humans — who usually ingest the organisms by eating food or water contaminated with tapeworm eggs or larvae — are often unaware they're carrying them. The parasitic organisms mature in the intestines and often result in few to no symptoms. When they do appear, signs and symptoms include abdominal pain, nausea and diarrhea. More severe infestations can cause complications, such as development of lesions or cysts in the liver, lungs or central nervous system.
A tapeworm infection that's confined to your intestines is easily treated with oral medications, and the prognosis for elimination is good. However, when the disease has migrated to other parts of the body, timely diagnosis and treatment is critical to help prevent permanent tissue damage. Untreated cases can be life-threatening.
The good news is that you can help prevent tapeworm infection with good personal hygiene, such as washing your hands before eating. You should also take special care when traveling in developing countries, since tapeworm infection occurs more frequently where sanitation is poor and people regularly eat raw or undercooked pork or beef. In fact, some studies have suggested that increasing travel to and immigration from these countries serve as a vehicle for the parasite's entry into the United States.
In humans, tapeworm disease is most commonly caused by one of three tapeworm species: the pork tapeworm (Taenia solium), beef tapeworm (Taenia saginata) and dwarf tapeworm (Hymenolepis nana). The fish tapeworm (Diphyllobothrium4 latum) also infects people in areas where raw freshwater fish is consumed.
|Tapeworm infection is usually caused by the ingestion of tapeworm eggs or larvae. Tapeworm eggs are generally ingested through food, water or soil contaminated with human or animal feces.
Larvae are usually ingested through undercooked pork or beef. For example, improperly-treated sewage containing tapeworm eggs may be used to fertilize pastures, which in turn infects pigs or cattle that graze in the area. Inside the animal's intestines, the eggs develop into pea-sized tapeworm larvae that are deposited in their tissues. The larvae can be passed on to humans who consume the meat.
As the tapeworm egg or larvae enters your system it migrates to the intestines, where it matures into an adult that can measure up to 50 feet long and can survive as long as 20 years. Some tapeworms attach themselves to the walls of the intestine, where they cause irritation or mild inflammation, while others may pass through to your stool and exit your body.
While being treated for tapeworm infection, you can re-infect yourself by ingesting tapeworm eggs shed by the adult worm into your stool. That's why you should take care to wash your hands after using the toilet.
Each segment of the tapeworm is capable of producing eggs. Larvae may stay confined to the intestines, or they may migrate through your tissues to other parts of the body and cause more serious complications.
Risk Factor :
Certain considerations may put you at greater risk of tapeworm infection, such as:
When to seek medical advice:
- Poor hygiene. Infrequent washing and bathing increases the risk of accidental transfer of contaminated matter to your mouth.
- Exposure to livestock. This is especially problematic in areas where human and animal feces are not disposed of properly.
- Frequent travel to developing countries. Infection occurs more frequently in areas with poor sanitation practices.
- Preference for eating raw or undercooked meats. Improper cooking may fail to kill any tapeworm eggs and larvae contained in contaminated pork or beef.
If you experience any of the signs or symptoms of tapeworm infection, you should immediately seek medical attention. Also contact your doctor if you believe you've been exposed to food or water contaminated with tapeworm or you've been traveling in areas with poor sanitation.
Most people who are infected with tapeworm don't show symptoms. However, you may notice tapeworm eggs, larvae or proglottids — segments of the adult tapeworm — in your stool.
Other signs and symptoms include:
More serious tapeworm infections can cause organ and tissue damage, resulting in vitamin deficiencies, fever or seizures.
- Loss of appetite
- Abdominal pain
- Weight loss
You may be able to self-diagnose infection by checking your stool for tapeworm eggs, larvae or parts of the adult tapeworm.
It's more likely you'll need your doctor to check your stool or send samples to a laboratory for testing. A laboratory may use microscopic identification techniques to check for eggs or tapeworm segments in your feces. The lab may need to collect two to three samples over a period of time to detect the parasite, since eggs and tapeworm segments are released irregularly into the stool.
Your doctor may also opt to test your blood for antibodies your body may have produced to fight tapeworm infection. The presence of the antibodies indicates tapeworm infestation.
For more severe cases of infection — where tapeworm larvae may have migrated outside your digestive tract — your doctor may order a radiograph, CT scan or MRI. Ultrasound imaging can also help determine the location of any larvae in your body or detect development of any lesions or cysts.
The consequences of tapeworm infection can vary, depending on what species of tapeworm you're infected with. The beef tapeworm, or T. saginata, can be relatively harmless, since it lives only in your intestine and is easily treated with medication.
However, infection with the larval phase of the pork tapeworm, or T. solium, can result in such complications as cysticercosis. These larvae can migrate to other tissues and organs throughout the body and develop into lesions or cysts. Lesions and cysts grow slowly over many months and can disrupt normal organ function, host a secondary infection or even rupture.
Neurocysticercosis is an especially dangerous complication of tapeworm infection. This disease affects the brain and central nervous system, resulting in headaches and visual impairment, as well as meningitis or dementia. Death can occur in severe cases of infection.
Echinococcosis infection is another complication that can follow the ingestion of the eggs of the echinococcus tapeworm, most commonly found in dogs or sheep. In humans the larvae that develop can migrate to organs — often the liver — and cause large cysts to develop. These cysts can place pressure on nearby blood vessels, hindering circulation or causing the blood vessels to rupture. Surgery or liver transplantation may be required in severe cases of infection.
The most common treatment for tapeworm infection involves oral medications that are toxic to the adult tapeworm, such as Praziquantel (Biltricide) and albendazole (Albenza). The medication prescribed depends on the species of organism involved.
The medications are poorly absorbed by your digestive tract and generally work by dissolving or attacking the adult tapeworm. Be aware that these drugs target the adult tapeworm, not the eggs, so take care to avoid reinfecting yourself. Always wash your hands after using the toilet and before eating.
Your doctor will check your stool samples at one month and three months after you've finished taking your medication. Successful treatment should render your stool free of tapeworm eggs, larvae or proglottids. The success rate is greater than 95 percent in patients who receive appropriate treatment.
In cases in which the tapeworm infection has migrated to tissues outside your intestine, your doctor may prescribe an anti-inflammatory steroid to reduce any swelling caused by the development of cysts.
Surgery may be required to remove any cysts that have developed in your liver, lungs or other organs, and organ transplantation may be your last resort in some cases.
To prevent tapeworm infection:
- Wash your hands with soap and water before eating or handling food and after using the toilet.
- When traveling in endemic areas, wash and cook all fruits and vegetables with safe water before eating.
- Eliminate your livestock's exposure to tapeworm eggs by properly disposing of animal and human feces.
- Thoroughly cook meat at temperatures of at least 150 F to kill tapeworm eggs or larvae.
- Freeze meat or fish for at least 12 hours to kill tapeworm eggs and larvae.
- Avoid eating raw or undercooked pork or beef.
- Promptly treat dogs infected with tapeworm.
|Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.