Gastrodiscoidiasis is a trematode infection seen primarily in Asia.
Name: Gastrodiscoides hominis
Type of trematode: amphistome. These are digenetic trematodes with (1) no oral sucker and (2) ventral sucker at the posterior end of the body.
Eggs: yellowish, oval, operculated, measuring 140 by 70 microns
Normal host: pigs
First immediate host: snail (Helicorbiscoenosus)
Second intermediate host: tadpoles, frogs, crayfish, other snails. The parasite can also encyst in aquatic plants.
Transmission: consumption of raw or undercooked aquatic vegetables, snails, frogs or crayfish
Countries affected include: Pakistan, Kazakhstan, India, Nepal, China, Thailand, Myanmar, Vietnam, the Philippines, Nigeria, Zambia
The adult worm inhabits the cecum and colon.
Human infections are often asymptomatic but also may be associated with diarrhea, colic, abdominal pain, or increased mucus production.
