Study on Metagonimus yokogawai(Katsurada, 1912) in Korea: IV. An epidemiological investigation along Tamjin River basin, South Cholla Do, Korea.

A status survey on Metagonimus yokogawai infection along the Tamjin River basin, South Cholla Do, Korea was conducted from September to November 1977. The snail intermediate host, Semisulcospira sp., the fish host, Plecoglossus altivelis and the inhabitants in three villages in Jangheung and Kangjin Guns were examined for detection of this trematode infection respectively. The results could be summarized as follows: 1. Out of 452 snails, Semisulcospira sp., 105 (23.2%) were found positive for rediae and/or cercariae of M. yokogawai in Jangheung Gun. 2. All of 20 sweetfishes, P. altivelis were infected with metacercariae of M. yokogawai and the mean number per fish was 15,688 and per gram of fish muscle, 234. 3. Out of 606 inhabitants in three villages, 160(26.4%) persons were found infected with M. yokogawai and the mean E.P.G counts per infected cases were 2,078. Sixty cases (9.8%) were positive for ova of Clonorchis sinensis with mean E.P.G., 846, frequently mixed-infected with M. yokogawai. From the above results, it was turned out that the Tamjin River basin is one of the endimic foci of metagonimiasis in Korea. The relatively low infection rate of human host in spite of much higher infection of intermediate hosts were considered to be due to the less population of sweetfishes in the Tamjin River than in the Sumjin River basin.