Teniasis is an infection caused by certain parasites called tapeworms. Parasites are small organisms that attach themselves to other living things (hosts) in order to survive. Parasites can be found in contaminated food and water. If you ingest contaminated material, you may contract a parasite that can then live (and sometimes grow and reproduce) inside of your body.
Teniasis is an intestinal tapeworm infection caused by eating contaminated beef or pork. Teniasis is also known by the following names:
- taenia sagniata
- taenia solium
- pork tapeworm
- beef tapeworm
You can develop teniasis by eating raw or undercooked beef or pork. Contaminated food can contain tapeworm eggs (larva) that, when eaten, grow in your intestines. Fully cooking beef or pork will destroy the larvae so that they cannot live in your body.
The tapeworm can grow up to 12 feet in length and can live in the intestines for years without being discovered. Tapeworms have segments along their bodies. Each of these segments can produce eggs. As the tapeworm matures, these eggs will be passed out of the body in the stool.
Poor hygiene can also cause the spread of teniasis. Once tapeworm larvae are in human stool, the parasite can be spread though contact with the stool. Proper hand washing is needed to help prevent the spread of the infection. Teniasis is more common in underdeveloped countries where sanitation and hand hygiene are often substandard. Although the infection is not commonly found in the U.S., people who travel to developing nations are at risk for contracting the disease (USDA, 2011).
Teniasis is more likely to develop in people that have weakened immune systems and are not able to fight off infections. Conditions that may weaken your immune system include:
- organ transplant
- patients undergoing chemotherapy
Most people that have teniasis do not have any symptoms. If symptoms are present they may include:
- unexplained weight loss
- blockage of the intestine
- digestive problems
In addition, some people with teniasis may experience irritation in the perianal area (area around the anus). This irritation is caused by worm segments or eggs being expelled in the stool. People often become aware that they have a tapeworm when they see worm segments or eggs passed in their stool. Infections can take between eight and 14 weeks to develop.
If you see worm segments or eggs in your stool, consult your doctor. Your doctor will ask you about your health history and recent travel outside of the U.S. Your doctor will often be able to make a diagnosis based on your symptoms. To confirm the diagnosis your doctor may order the following tests:
- blood tests including a complete blood count (CBC)
- stool exam to see if eggs or worm segments are present
Teniasis is typically treated by medications prescribed by your doctor. Medications for the treatment of teniasis include praziquantel and albendazole. Both drugs are antihelminitics, a classification of drugs designed to kill parasitic worms and their eggs. In most instances these medications are provided in a single dose; however, these medications can take a few weeks to fully clear an infection. The tapeworm will be excreted as waste. Common side effects associated with these medications include dizziness and upset stomach.
Most cases of teniasis infection go away with treatment. Medications prescribed for this condition are typically effective and will cure the infection.
In some cases, some people develop serious complications from the infection. Tapeworms may block your intestines. This may require surgery to correct. In some cases, the tapeworm may travel to other parts of the body such as the heart, eye, or brain. This condition is called cysticercosis, and it can cause other health problems including seizures or infections in the nervous system.
The most effective way to prevent teniasis is to cook food thoroughly. This means cooking meat to a temperature above 140 degrees Fahrenheit for five minutes or more. Measure the meat temperature with a cooking thermometer. After cooking meat, allow it to stand for three minutes before cutting it. This can help destroy any parasites that may be in the meat.
In the U.S., laws requiring the inspection of animals and meat help reduce the chance that tapeworms will be spread.
Proper hand hygiene is also important for preventing the spread of this disease. Always wash your hands after using the bathroom. If you travel to an area where sanitation is substandard, consider drinking bottled water.