Epidemiological Study On Metagonimus Yokogawai Infection Along Boseong River In Jeonra Nam Do, Korea

Prevalence study of Metagonimus yokogawai infection, survey of intermediate hosts of Metagonimus yokogawai and food habits of raw sweetfish among inhabitants along Boseong river (120 km), Jeonra Nam Do (province) were carried out. The results are summarized as follows: 1. Among 360 examined, the egg positive case were 128(35.6%); male 112(46.7%), female 16(13.3%). 2. The prevalence rates were different by geographical areas; 42.4% in down stream, 49.4% in middle stream and 13.3% in upper stream. 3. By ages, highest rate, 53.6~59.1% was observed among 30~49 group (male 69.6~73.0%, female 15.8~35.5%). 4. Eggs per gram of feces were 2,084 (200~12,280) in average; down stream 1,708, middle stream 2,590, upper stream l,550. 5. By social strata, the prevalence showed differences; 24.8% in primary schoolchildren, 78.4% in school teacher and local officers, 30.6% in general inhabitants. 6. Clonorchis sinensis infected cases in the areas were 21(5.8%) out of 360 examined, and 90.5% of them showed mixed infection with Metagonimus yokogawai. 7. Cercariae of Metagonimus yokogawai from the lst intermediate host, Semisulcospira sp., in down and middle streams were detected from 32 snails (5.9%) out of 545 examined. 8. All the 22 Plecoglossus altivelis which were caught from the down stream were infected with metacercariae of Metagonimus yokogawai. The number of the metacercariae detected was 22,650 per fish in average, and the number increased from August to October. 9. Experiences of raw sweetfish intake of the inhabitants were found in 208(58.4%) among 356 interviewed by questionaire form (male 76.7%, female 20.7%). 10. Means of acquisition of the sweetfish were mostly by purchase 68.8%, and seasonally in summer. 11. Reason of the raw sweetfish intake was due to the flavor, 83.2%. The fish were mixed in soy sause with vinegar before the intake.