A mass fecal examination was performed in Seoul, Korea from December 1983 to March 1984 and 15 egg positive cases of Fibricola seoulensis were discovered. They were treated with praziquantel(Distocide) 20 mg/kg single dose and magnesium salt for purgation. The adult worms of F. seoulensis were collected from 6 of them. The number of the flukes ranged 1-78 by the case. The cases had no clinical mainfestation at all. They were all Korean males in twenties, and had the histories of eating the roast or raw snakes or frogs. Fibricoliasis is expected to be prevalent among the snake-eaters in Korea. Further cases will be detected by sedulous differentiation of thin-shelled immature operculated eggs of 0.081-0.102mmn length. Praziquantel seems to be an excellent chemotherapeutic for fibricoliasis.
