What is a tapeworm?
Tapeworms are a type of parasite that live in the intestines of animals. They have a head, neck, and many body segments called proglottids. They lay eggs, which then hatch into larvae before maturing into an adult tapeworm.
Humans can become infected by eating eggs or larvae in contaminated water or meat. The infection in humans is usually easily treated but sometimes it can cause serious problems.
If a human or an animal consumes tapeworm eggs, the eggs hatch into larvae, which break through the wall of the intestines and grow inside cysts in tissues or organs. These can cause life-threatening damage.
If you consume tapeworm larvae, they can develop into adult tapeworms in the intestines. They attach to the wall of the intestine with suckers or hooks, and remain there to feed and grow. An adult tapeworm can be very long and live in the intestine for many years.
The most common tapeworm infection in Australia is caused by dwarf tapeworm. There is also a risk in Australia of contracting a serious condition called hydatid disease from the eggs of a type of tapeworm called Echinococcus granulosus found in dog faeces (poo). You should see your doctor if you have any signs of tapeworm infection.
It is also possible to be infected by other types of tapeworm overseas.
What are the symptoms of tapeworm infection?
People with tapeworm infection often have no symptoms. If you have symptoms, they will depend on the type of tapeworm and where it is in your body.
Intestinal tapeworm infection can cause:
- pain in the abdomen (tummy)
- weakness or tiredness
- loss of appetite
- weight loss
- vitamin and mineral deficiencies
- pieces of worm in the faeces
If you develop a complication you may have:
If you have hydatid disease, you may have fluid-filled cysts in the body. These most commonly grow in the liver or lungs, but can grow in any organ including the brain, heart or bones. The cysts normally do not cause problems unless they grow very large or break.
What causes tapeworm infection?
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 is tapeworm infection diagnosed?
Your doctor will ask for a stool sample and perhaps a blood test to confirm that you have tapeworms and what kind of tapeworm you have.
If you have hydatid disease, you may need an x-ray, ultrasound, or MRI scans to diagnose the cysts.
How is tapeworm infection treated?
You will probably be prescribed medicine to kill the tapeworms.
If you have hydatid disease, you may need other medication and perhaps surgery to remove the cysts.
Can tapeworm infection be prevented?
You can reduce your risk of tapeworm infection by:
- washing your hands after using the toilet and before handling food
- following food handling guidelines
- not eating undercooked pork, beef and fish
- controlling tapeworm infection in your dog, with preventive deworming and quickly treating any dog infected with tapeworm
- not letting a dog lick your face
- not feeding dogs raw offal
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Last reviewed: April 2021