Entamoeba histolytica is a single-celled parasite that causes amoebic dysentery, a severe intestinal infection. It is primarily transmitted through contaminated food and water, especially in areas with poor sanitation. Once ingested, the parasite can invade the intestinal lining, leading to symptoms such as diarrhea, abdominal pain, and fever. This organism is found worldwide, but it is more common in tropical and subtropical regions. Diagnosis typically involves stool tests to identify the parasite, and treatment usually includes medications like metronidazole. Preventive measures focus on improving hygiene and sanitation to reduce the risk of infection.