A flatworm is any of several types of parasitic worm with a flat body — the tapeworms and flukes that infest the intestines, liver, and tissues of humans and animals. The group includes Taenia tapeworms, acquired from undercooked pork or beef carrying larval cysts; the liver flukes Fasciola hepatica and Fasciola gigantica from aquatic plants; and the blood flukes of schistosomiasis from contaminated water. Their flat, ribbon-like bodies are built for the parasitic life: no digestive system in the tapeworms, which absorb nutrients through their skin; complex life cycles running through intermediate hosts. Food safety meets flatworms at the points of transmission — thorough cooking of meat, washing of water plants, safe water. They are the shape of parasitism made visible: flat, clinging, and patient.