Most people know you can get tapeworms from eating under-cooked pork and fish. You can even get parasites from your children who picked up the little freeloaders from their friends at school. You can also get parasites from eating raw vegetables on which the tiny parasite eggs are laid. Sex also spreads parasites and they are more easily passed than venereal diseases. Symptoms of parasitic infestation run a wide range.
Roundworms cause fever, cough and intestinal problems.
Hookworms cause anemia, abdominal pain, diarrhea, apathy, malnutrition and even under-development in children. Whipworms cause abdominal pain and diarrhea. The fecal matter from a single tapeworm can make humans sick. The worms can become so numerous as to cause intestinal obstruction as well a gas. Tapeworm eggs in the liver can be mistaken for cancer tumors.