Echinostoma is a genus of trematode parasites, which can infect both humans and other animals. These intestinal flukes have a three-host life cycle with snails or aquatic organisms as intermediate hosts, and a variety of animals, including humans, as their definitive hosts. Echinostoma infect the gastrointestinal tract of humans, and can cause a disease known as echinostomiasis. The parasites are spread when humans or animals eat infected raw or undercooked food, such as bivalve molluscs or fish