intestinal parasite infection intestinal parasite infection an intestinal parasite infection is a condition in which a parasite infects the gastro-intestinal tract of humans and other animals. such parasites can live anywhere in the body, but most prefer the intestinal wall. intestinal parasitehuman gastro-intestinal systemspecialtyinfectious disease routes of exposure and infection include ingestion of undercooked meat, drinking infected water, fecal-oral transmission and skin absorption. some types of helminths and protozoa are classified as intestinal parasites that cause infection—those that reside in the intestines. these infections can damage or sicken the host (humans or other animals). if the intestinal parasite infection is caused by helminths, the infection is called helminthiasis. signs and symptoms signs and symptoms depend on the type of infection. intestinal parasites produce a variety of symptoms in those affected, most of which manifest themselves in gastrointestinal complications and general weakness. gastrointestinal conditions include inflammation of the small and/or large intestine, diarrhea/dysentery, abdominal pains, and nausea/vomiting. these symptoms negatively impact nutritional status, including decreased absorption of micronutrients, loss of appetite, weight loss, and intestinal blood loss that can often result in anemia. it may also cause physical and mental disabilities, delayed growth in children, and skin irritation around the anus and vulva. cause