Photos: What to know about tapeworms and parasites Cyclosporiasis: An intestinal infection caused by the cyclospora cayetanensis parasite, seen here on a stool sample through a microscope on a slide. Cyclospora infect the small intestine and most commonly cause watery diarrhea; other symptoms include abdominal cramping, nausea and weight loss. Hide Caption 1 of 8

Photos: What to know about tapeworms and parasites Trichinella spiralis: If a human or animal eats meat infected with Trichinella cysts, the Centers for Disease Control and Prevention says, their stomach acid dissolves the hard covering of the cysts. The worms pass into the small intestine, where they lay eggs that develop into immature worms, which travel through the arteries and into the muscles. There, they curl up and return to the original cyst formation, and the life cycle continues. Symptoms can include nausea, diarrhea, vomiting, headaches, fevers, chills, cough, facial swelling, aching joints and muscle pain. Hide Caption 2 of 8

Photos: What to know about tapeworms and parasites Anisakiasis: The nematodes parasite of the genus anisakis causes an illness caused by eating parasite-contaminated raw fish or seafood. The anisakid nematodes can invade the stomach wall or intestines, causing symptoms of gastrointestinal pain, nausea and vomiting. Some people will develop complications, including digestive bleeding and peritonitis, inflammation of the inner wall of the abdomen. An allergic response to the worm can cause life-threatening anaphylaxis. Hide Caption 3 of 8

Photos: What to know about tapeworms and parasites Tapeworm, aka Neurocysticercosis, aka T. solium: This is Taenia solium, the pork tapeworm that causes one of the grossest diseases we're heard about in a while. It's responsible for the worst headache of Luis Ortiz's life. When surgeons looked in his brain, they found a "wiggling" tapeworm inside a cyst. That's called neurocysticercosis, and the Centers for Disease Control and Prevention says that about 1,000 people a year get them from eating something infected with "microscopic eggs passed in the feces of a person who has an intestinal pork tapeworm." Hide Caption 4 of 8

Photos: What to know about tapeworms and parasites Chagas disease, aka T. cruzi: This nasty disease comes from a bug called a triatomine that's infected with the Trypanosoma cruzi parasite. The CDC estimates there are at least 300,000 people living with the disease in the U.S. right now, but they may not know it. It unusually takes years of chronic infection before heart disease, heart failure and gastrointestinal problems begin.

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Photos: What to know about tapeworms and parasites Toxocariasis T. canis and T. cati: Your precious pooch and sweet kitty can carry a nasty parasite. It's caused by the larval form of the roundworms that infect puppies, kittens and adults of both species that aren't dewormed.

Called Toxocara canis in dogs and Toxocara cati in cats, the roundworm eggs are excreted in feces, and if you (or your child) accidentally ingest infected dirt, they travel to organs and tissues, hatch and do their nasty thing.

Though not common, it's bad: The CDC says 70 people, mostly children, are blinded by the disease each year. Hide Caption 6 of 8

Photos: What to know about tapeworms and parasites Cat-scratch fever, aka toxoplasmosis or T. gondii: Toxoplasmosis infects more than a million people each year in the US. Once you get it, you've usually got it for life, the CDC says. Hide Caption 7 of 8