A tapeworm infection that affects the liver, lungs, brain and other organs. Echinococcosis is spread by contact with animal faeces contaminated with tapeworm eggs. Sources include contaminated food, water and animal fur. Cysts containing tapeworm larvae may grow in the body for years before symptoms appear. When cysts become large, they may cause nausea, weakness, coughing and stomach or chest pain.Treatment may include surgery, removal of fluid from the cysts and medication.