What flatworms are dangerous to humans?

Flatworms are parasites (helminths) that cause helminthiases (diseases associated with the carriage of the parasite).
The hepatic fluke (fluke) causes trematodosis. An adult of this worm lives in the liver of a person or cattle, where it self-fertilizes and the eggs enter the intestines, then into the environment. For development, the egg enters the water, the larva hatches and is drilled into a small pond snail. There it multiplies until the pond snail bursts. A person will become infected by drinking water from a reservoir with larvae.