An infection that is caused by nematodes of the genus Gnathostoma, which is commonly found in Southeast Asia, and which is transmitted via the consumption of contaminated raw/undercooked birds, eels, fish, frogs, or reptiles. The pattern of symptoms is species-dependent, and extraintestinal manifestations are due to larval migration (e.g., pulmonary infiltrates, eosinophilic meningitis, or painful, pruritic subcutaneous swellings, and peripheral blood eosinophilia).