BACKGROUND: The infection rate of intestinal parasites has been abruptly decreased during a couple of decades, but the report that Clonorchis sinensis has been decreased in infection rate was not shown. Because Clonorchis sinensis could induce the serious complications such as cholecystitis, cholelithiasis, cholangiocarcinoma, authors thought that clonorchiasis requird early diagnosis, treatment and prevention. Therefore the authors surveyed the infection pattern of Clonorchis sinensis for inhabitants who lived in Miryang city, well-known as endemic area for a long time, located at lower basin of Nakdong river. METHODS: The 661 subjects that received workers health examination in Miryang Youngnam General Hospital from September to November, 1996, were surveyed by using questionnaire, skin test and stool egg examination. This questionnaire contained history, duration, frequency of raw freshwater fish ingestion, history and treatment of clonorchiasis, history of other hepatic disease. The authors performed laboratory examination to 54 stool egg positive subjects. RESULTS: Among 661 subjects, the stool egg positive subjects were 54 and showed 8.2% in infection rate. In male(8.9%), stool egg positive rate was higher than female(4.9%). As age increased, stool egg positive rate also increased. Compared to the age group less than 30, stool egg positive rate was higher among age group 30 or over, particularly, in age group 50 or over, stool egg positive rate showed highest infection rate, 31.6%. And stool egg positive rate was increased according to increase of period, frequency of raw freshwater fish ingestion. Subjects with history of clonorchiasis and administrating Praziquantel had higher infection rate than the other subjects without the history. CONCLUSIONS: In this survey, the authors thought that high risk factors of clonorchiasis were male, age of 30 or over(particularly age of 50 or over), more than 10 years in raw freshwater fish ingestion period, more than twice per month in raw freshwater fish ingestion frequency. Then people having these risk factors must be performed various examinations for clonorchiasis, although they had not clinical symptoms, signs and abnormal laboratory findings.
Cholangiocarcinoma ; Cholecystitis ; Cholelithiasis ; Clonorchiasis ; Clonorchis sinensis* ; Early Diagnosis ; Eating ; Fresh Water ; Gyeongsangnam-do ; Hospitals, General ; Humans ; Male ; Ovum ; Parasites ; Praziquantel ; Risk Factors ; Rivers* ; Skin Tests ; Surveys and Questionnaires