A study was required to evaluate the prevalence of clonorchiasis among school children in the 7 differnet schools located near the Gumho basin and to determine the effectiveness of the anticlonorchis campaign conducted in that area. Surveys for Clonorchis sinensis and the worm burden in the same areas were compared for the period 1960-1970. Both surveys concentrated on children in grades 1-3 ranging from 6-11 years old. They were examined using primarily intradermal tests with Clonorchis antigen and followed by stool examinations. Stool examinations consisting of the formalin-ether sedimentation(Ritchie, 1948 ) and the Stoll egg-count techniques were performed in those cases which revealed positive and doubtful intradermal reactions. The overall prevalence rate for clonorchiasis was reduced from 13.4 per cent to 4.1 per cent. There was also a significant reduction in the worm burden, suggesting that no clonorchiasis will be found among chileren in the near future. In connection with this survey, the prevalence rate for intestinal helminths in 1960 was compared with 1970. The rate for Ascaris lumbricoides had decreased, while the rates for Trichuris trichiura and Trichostrongylus species had increased. No fluctuation in the rate of hookworm was observed during the past 10 years. Clearly, the present survey denotes a requirement for a combined procedure of health education and mass survey with intradermal testing. It has been found that these methods not only greatly reduce the prevalence of clonorchiasis but also is followed by the marked reductions of the worm burdens of the children examined.
parasitology-helminth-trematoda-nematoda ; Clonorchis sinensis ; Ascaris lumbricoides ; Trichuris trichiura ; Trichostrongylus species ; epidemiology

To evaluate the Kato's cellophane thick smear techcique in detection ability of various helminth ova, authors examined 1,843 nationwidely collected stool specimens by the two methods, formalin-ether technique and cellophane thick smear technique. And the results were analyzed. The positive rates of following helminth ova were superior in cellophane thick smear technique to those of formalin-ether technique: Ascaris lumbricoides(62.3% : 51.1%), Taenia species (1.5% : 0.9%). The difference in A. lumbricoides ova detection is highly significant one. The overall positive rate for helminths ova was also higher in Kato's method (92.3% : 90.0%). The positive fates of following helminth ova were infrior in cellophane thick smear technique to those of formalin-ether technique: Hookworm (5.8% : 14.6%), Trichostrongylus orientalis(3.2% : 17.8%), Clonorchis sinensis(8.3% : 11.0%), Metagonimus yokogawai (0.6% : 1.7%) and Hymenolepis nana(0.05% : 0.3%). The positive rate for the ova of Trichocephalus trichiurus by the two methods was incidentally same, 74.1%. The causes of inferior positive rates in some helminth ova by cellophane thick smear technique were shortly discussed and suggests some opinions in improvement of detection ability.
parasitology-helminth-nematoda ; diagnosis ; Ascaris lumbricoides ; Taenia species ; Hookworm ; Trichostrongylus orientalis ; Clonorchis sinensis ; Metagonimus yokogawai ; Trichocephalus trichiurus

A survey of intestinal parasites infection among Korean people has been carried out during July 1969 to December 1970. A total of 2,250 stool specimens (male 1,101, female 1,146) was collected from all the provinces and Seoul city in Korea. The specimens were examined routinely by direct fecal smear, zinc sulfate flotation and formalin-ether sedimentation techniques. The results are summarized as follows: Of 2,250 specimens examined, l,803(80.l per cent) were positive for intestinal parasites. The positive rates of intestinal helminths were 1,644(73.1 per cent) among 2,250; Ascaris lumbricoides 46.0 per cent, Trichocephalus trichiurus 46.8 percent, hookworm 6.8 per cent, Trichostrongylus orientalis 7.0 percent, Clonorchis sinensis 12.1 percent, Enterobius vermicularis 1.6 per cent, Hymenolepis nana 0.7 percent, Taenia species 0.3 per cent, Metagonimus yokogawai 0.04 percent, Fasciolidae 0.04 per cent and one case of lung fluke Paragonimu westermani. The positive rstes of intestinal protozoa were 786(34.9 per cent); Entamoeba histolytica 6.4 per cent, Entamoeba coli 20.5 percent, Endolimax nana 10.0 per cent, Giardia lamblia 5.1 per cent, Trichomonas hominis 1.1 percent, Chilomastix mesnili 0.5 percent, Iodamoeba butschlii 0.6 percent, Enteromonas hominis 0.7 percent, Dientamoeba fragilis 0.1 per cent and one case of Isospora hominis. Sexual distribution of helminths and protozoan infections showed higher rate in female than that of male, except C. sinensis, H. nana, Taenia species or G. lamblia Infections of T. trichiurus, hookworm, T. orientalis, C. sinensis, Taenia species, E. histolytica, E. coli and E. nana increased with age. Conversely, H. nana and G. lamblia infections were more predominent in younger ages.
parasitology-helminth-protozoa-trematoda-nematoda-cestoda ; Ascaris lumbricoides ; Trichocephalus trichiurus-Trichuris trichiura ; hookworm ; Trichostrongylus orientalis ; Clonorchis sinensis ; Enterobius vermicularis ; Hymenolepis nana ; Taenia species ; lamblia ; Trichomonas hominis ; Chilomastix mesnili ; Iodamoeba butschlii ; Enteromonas hominis ; Dientamoeba fragilis ; Isospora hominis ; epidemiology ; stool examination

For seven years from 1962 to 1968, fecal specimens of the patients were examined not only for the discovery of intestinal protozoa and helminths, but also to provie data on the incidence of intestinal parasites among the residents of Kyungpook Province, Korea. The Formalin-ether sedimentation, Lugol solution, and Heidenhain's iron-hematoxylin stained films were prepared for the recovery of intestinal parasites. Of 2,414 samples of feces examined, 35.7 percent were found to be infected with one or more species of protozoa. Among six species of protozoa detected, Entamoeba coli was observed most frequently(15.3%) followed by Entamoeba histolytica (11.9%), and then the Enteromonas hominis least often(1 case). For the survey of helminth, of a total of 5,288 fecal specimens examined, 86.7 percent were positive for one or more species of helminths. Trichocephalus trichiurus revealed the highest infection rate (83.6%), while Trichostrongylus orientalis was next (61.6%), and Ascaris lumbricoides was unexpectedly low(40.9%). The incidence for hookworm and Clonorchis sinensis was 22.4 percent and 29.8 percent respectively. Triple infections were found more frequently than double infections, and mixed infections of six or more species of helminths were observed in 3.8 percent of specimens.
parasitology-helminth-protozoa-nematoda-cestoda-trematoda ; Entamoeba coli ; Entamoeba histolytica ; Enteromonas hominis ; Endolimax nana ; Iodamoeba butschlii ; Giardia lamblia ; Trichocephalus trichiurus ; Trichostrongylus orientalis ; Ascaris lumbricoides ; hookworm ; Clonorchis sinensis ; Enterobius vermicularis ; Paragonimus westermani ; Metagonimus yokogawai ; Taenia species ; epidemiology ; stool examination ; Formalin-ether ; sedimentation ; Lugol solution ; Heidenhain's iron-hematoxylin