Newly found endemic foci of Clonorchis sinensis in Kyungpook Province, Korea.

Nishimura in 1943 indicated for the first time that a serious endemic focus of Clonorchis sinensis is located in the vicinity of Yeong-cheon(Kyungpook Province, Korea). Later, numerous surveys of this fluke in the Province have been made, but no additional report on the endemic focus of the fluke has been available. The overall percentage of Clonorchis sinensis infections, based on the discovery of eggs by the formalin-ether sedimentation technique, was found to be 54.8 percent from 851 residents in Nakjeon ri (village), Danmil myun, Uiseong gun (county), Kyungpook Province and no significant difference was observed in the sex specific rate of the individuals infected. There is a high incidence of infection with Clonorchis sinensis. The infection rate in the age group from 0 to 4 years was 14.6 per cent, 5 to 9 years was 35.7 per cent and 10 to 14 years was 51.7 per cent. In the worn burdens for residents, the average number of egg-counts was 41,800. It is found that a serious endemic focus of Clonorchis sinensis exists in the vicinity of Nakjeon village.