E. histolytica is a single-celled parasite that causes amoebic dysentery in humans. It primarily resides in the intestines and can lead to severe gastrointestinal symptoms, including diarrhea, abdominal pain, and dehydration. The parasite is transmitted through contaminated food and water, making sanitation and hygiene crucial for prevention. Infection with E. histolytica can be diagnosed through stool tests or imaging studies. Treatment typically involves medications such as metronidazole or tinidazole. If left untreated, the infection can lead to serious complications, including liver abscesses, highlighting the importance of early detection and proper medical care.