Transmission
Transmission requires two intermediate hosts, the first of which is snails, most commonly of species Semisucospira libertine, Scoreana, and Thiara granifera.
Semisulcospira Snail
Infection is acquired through the secondary intermediate host, fish, that haven’t been thoroughly cooked. Metacercariae encyst under the scales or in the flesh of fish from fresh or brackish water. Sweetfish (Pecoglossus altevelis) is one of the most common fish species infected, but other include the golden carp (Carassius auratus), common carp (Cyprinus carpio), Zacco temminckii, Protimus steindachneri, Acheilognathus lancedata, and Pseudorashora parva.
Definitive hosts include humans and various fish-eating mammals, primarily dogs, cats, and pigs. Fish-eating birds may also be infected with metagonimiasis.
Read more about this topic: Metagonimiasis