Tapeworm Symptoms and Prevention
Let's assume that, after reading all of this, you've decided against intentionally acquiring a tapeworm. How can you prevent them? First, practice excellent hygiene by thoroughly washing hands with soap and warm water after every bathroom visit and before handling or eating food. Doing so will greatly minimize your chances of becoming an unwitting host.
The good news is that, in the United States at least, inspection of meat keeps tapeworms out of the food supply. You apparently can see the cysts in the meat if you know what to look for. In addition, thoroughly freezing meat at minus 31 degrees Fahrenheit (-35 degrees Celsius) for 10 days will kill any parasites [source: Mayo Clinic].
Also, if you're cooking meat resist the urge to make it rare and instead cook to a safe temperature to effectively kill larvae and eggs. Always use a food thermometer, and for whole cuts of meat (not poultry, though) cook to a minimum of 145 degrees Fahrenheit (63 degrees Celsius), making sure to let it "rest" for at least three minutes before cutting. This resting period (where the meat is off the fire but not yet carved) will kill off pathogens. Ground meats should also be cooked carefully, to a temp of 160 degrees Fahrenheit (71 degrees Celsius) but don't require a resting period [source: CDC].
If you're traveling to or living in a developing area of the world, take extra precautions by using safe water to thoroughly wash and cook veggies and fruits. If you're not sure about the water quality boil it for a minute and allow to cool. Also, avoid contact with animal and human feces by making sure they're properly disposed of, particularly in a livestock-relevant situation.
Tapeworm infections often give off no symptoms, but if you notice weakness, nausea, abdominal pain, diarrhea, dizziness, loss of appetite, weight loss and salt craving it's worth a visit to the doctor to be assessed for possible intestinal infection. Usually a stool sample will be checked for tapeworm segments or eggs. Signs of a more serious, invasive infection include headaches, allergic reaction, seizures, other neurological symptoms and cystic lumps [source: Mayo Clinic].
Ideally, such an event will be caught long before it gets too serious, when it can be quickly handled by a single dose of niclosamide or praziquantel, anti-worm medications, which will kill the parasite by forcing all its muscles to permanently contract. The tapeworm will then leave your body along with your feces [source: CDC]. Severe cases may require surgery.