A new endemic focus of Heterophyes nocens, Pygidiopsis summa, and other intestinal flukes in a coastal area of Muan-gun, Chollanam-do.

A small coastal village of Muan-gun, Chollanam-do, was surveyed for intestinal fluke infections, especially heterophyids such as Heterophyes nocens and Pygidiopsis summa by fecal examination on 108 inhabitants. The egg positive rate of heterophyids was very high, 75.0%, and that of other parasites was comparatively low, 0.9-3.7% by parasite species. After treatment of 20 patients showing high E.P.G. with praziquantel and purging with MgSO4, total 3,864 specimens of H. nocens were collected from the diarrheic stools of all the patients treated (3-1,338 individually) and total 703 P. summa were harvested from 18 patients (1-170 individually), together with several other species of flukes. Other flukes included Stictodora fuscata (164 specimens from 4 patients), Heterophyopsis continua (2 from 2 patients), and Gymnophalloides seoi (4 from 3 patients). From this study, the surveyed coastal area of Muan-gun, Chollanam-do was proven to be a new endemic focus of H. nocens and P. summa. The occurrence of a few infected cases suggests that this area should also be a low-grade endemic area of S. fuscata, H. continua, and G. seoi.