The Alaria alata is a development stage of a trematode. It multiplies in the intestines of the final host, which are as a rule animals which eat game meat. Through faeces the eggs are excreted into the environment. The further development of the parasites then occurs through two intermediate hosts, snails and frogs. If so-called paratenic hosts, such as wild boar, take up infected frogs or other paratenic hosts, the development stages of this parasite (mesocercariae) infest the muscles or neighbouring organs and tissues. In this way humans can be infected, too and contract an alariosis. Information on the occurrence and significance of this disease is currently not available for Germany.