Thin layer immunoassay was carried out to demonstrate antibodies against Clonorchis sinensis in sera from clonorchiasis patients. Saline extract of adult worm was used as antigen. TIA technique was performed as described earlier by Elwing et al. (1976), but agarose was used instead of agar. The antibody titres of sera in 60 clonorchiasis cases were higher than that of 10 healthy and 10 amoebiasis cases, but not different comparing with that of 10 paragonimiasis cases. Antibody titres in clonorchiasis gave no differences according to the age, sex, EPG in feces, eosinophilia degree of blood, level of alkaline phosphatase and transaminase (SGOT, SGPT) in sera. It is suggested that, after evaluation, the TIA might supplement or be used as an alternative to other immunodiagnostic tests already in use for the diagnosis of clonorchiasis.
parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis ; immunology

Thin layer immunoassay was carried out to demonstrate antibodies against Clonorchis sinensis in sera from clonorchiasis patients. Saline extract of adult worm was used as antigen. TIA technique was performed as described earlier by Elwing et al. (1976), but agarose was used instead of agar. The antibody titres of sera in 60 clonorchiasis cases were higher than that of 10 healthy and 10 amoebiasis cases, but not different comparing with that of 10 paragonimiasis cases. Antibody titres in clonorchiasis gave no differences according to the age, sex, EPG in feces, eosinophilia degree of blood, level of alkaline phosphatase and transaminase (SGOT, SGPT) in sera. It is suggested that, after evaluation, the TIA might supplement or be used as an alternative to other immunodiagnostic tests already in use for the diagnosis of clonorchiasis.
parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis ; immunology

The infection rates with cercaria and metacercaria of the Clonorchis sinensis in snail and fish hosts, and the prevalence among the inhabitants in the lower Nag Dong river in Busan were investigated in the period from June 1981 to March 1982. The stool examination and E.P.G. count for prevalence and intensity of clonorchiasis were done by cellophane thick smear and Stoll's egg count methods. The prevalence rate of clonorchiasis among inhabitants of 3 towns in Bug Gu, was 38.4% among a total of 1,384 persons examined. By town, the prevalence in Gu Po was 25.4% out of 330 persons examined, 39.3% in 438 examined in Gang Dong and 44.8% out of 616 in examined in Myeng Ji respectively. According to sex, the male(41.9%) showed relatively higher rate than female(35.3%). By age, increase of rate was observed as increase in age. The highest rate was 80.7% in 50-59 years group. The intensity of infection was light: 89.1% of examined cases were below 10,000 E.P.G. ; by area 80.9%(Gu Po), 80.2%(Gang Dong), 97.3%(Myeng JI). Out of fresh water fish species collected, 2 species were not infected with metacercaria. The metacercarial detection rate from fish in low Nag Dong river showed 100% in Pseudorasbora parva, Pseudogobio esocinus(41.4%), Hemibarbus labeo(37.1%), Acheilognathus limbata(33.3%) and Erythroculter erthropterus(4.5%) respectively. The mean number of metacercaria per gram of muscle was 21.2 in P. parva, P. esocinus(15.0), H. labeo(11.9), A. limbata(6.3), and E. erythropterus(1.6) respectively. Though 7 area along Nag Dong river were surveyed for Parafossarulus manchouricus, the snails were not found at all areas except for one area, Seo Nam stream; and the cercaria was infected 0.9% out of 708 examined.
parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis-epidemiology ; host

To understand the mode of transmission in clonorchiasis, a survey was made in Kim-hae Goon, South Kyong-sang Do (=Province). The mathematical analysis of the age prevalence was done on the egg positive rates. And another analysis for the comparison was also made to the cited data from two areas, North Kyong-sang Do and Ko-yang Goon, Kyong-gi Do. Some catalytic models of H. Muench (1959) were applied to the observed age prevalence. Because the both parameters, such as force of infection(a) and loss of positivity(b) were considered to be constant for a long period in the surveyed area, the two stage catalytic model by Muench was chosen to the analysis. In the surveyed area, Kim-hae Goon where the egg positive rates were 56.2 percent and 61.2 percent (by Kim, 1974), the constant values of 'a' were found to be 0.051 and 0.089 respectively. In other words, the force of infection was 51, 89 per 1,000 susceptibles. The values of 'b' were found to be 0.006 and 0.005. This means that the rates of disappearance from egg positive cases to negative were 6 and 5 per annum per l,000 positive cases in above area. Therefore, the two catalytic curves were expressed by the following equations, y = 1.133 {e(-0.006t) - e(-0.051t)} and y = 1.047 {e(-0.005t) - e(-0.089t)} respectively. In the cases of North Kyong-sang Do and Ko-yang Goon, Kyong-gi Do where the egg positive rates of clonorchis shown as 27.7 percent and 15.2 percent by Shin (1964) and Kim (l974), the curves were expressed by y = 1.769 {e(-0.010t) - e(-0.034t)} and y = 2.857 {e(-0.020t) - e(-0.027t)} respectively. From the above mathematical analyses by age prevalence in clonorchiasis, it was considered that the mode of transmission of clonorchiasis in the surveyed area, Kim-hae Goon presented more rapid pattern than those of North Kyong-sang Do and Ko-yang Goon, Kyong-gi Do.
parasitology-helminth-trematoda ; clonorchiasis-Clnorchis sinensis ; epidemiology ; transmission

This study was undertaken to evaluate the effects of health education and anti-Clonorchis campaign conducted in Kyungpook Province and to compare the prevalence of Clonorchis sinensis among the residents in the same areas for the period 1964-1976. Both surveys were made on all age groups of residents ranging from 0 to over 60 years of age. They were examined using primarily intradermal tests with Clonorchis and Paragonimus antigens and followed by stool examinations. The definitive diagnosis of clonorchiasis was made on the recovery of Clonorchis eggs from the stools. A marked reduction in the prevalence was encountered in the youngest age group, but there is no significant difference in the older age groups. The overall prevalence rate for clonorchiasis was reduced from 27.7 to 19.6 per cent in a period of 10 years. It is found that clonorchiasis is less prevalent in Kyungpook Province than it was a decade ago and it continued to decline.
parasitology-helminth-trematoda ; Clonorchis sinensis-clonorchiasis ; Paragonimus westermani ; epidemiology

In an attempt to determine the susceptibility of inbred golden hamsters(Mesocricetus auratus) to the experimental infection with Clonorchis sinensis, twenty-five hamsters were divided into 5 groups and administered orally 5, 10, 20, 30 or 50 metacercariae each. The hamsters were killed on the 45th day after infection. The adult flukes were recovered from all hamsters. The overall recovery rate for the fluke was 57.9 percent with the range of 48.4 percent to 92.0 percent. As the number of the metacercariae given increased, a proportionate decrease in the recovery rate was found. The prepatent period of the fluke in the hamster varied from 16 to 17 days, with the average of 16 days. No significant differences in the development of the flukes were observed. Egg production expressed by EPG, increased step by step as the time elapsed. However, a tendency of decreasing egg laying capacity was observed with the increase of worm burden. It is suggested that the hamster is a suitable final host of C. sinensis.
parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis ; susceptibility ; golden hamster

Among several diagnostic tools for clonorchiasis (Clonorchis sinensis infection), radiologic examinations are commonly used in clinical practices. During the 2 past decades, many reports regarding imaging findings of clonorchiasis were introduced. The basic imaging finding of clonorchiasis is diffuse dilatation of the peripheral intrahepatic bile ducts, without dilation of the large intrahepatic or extrahepatic bile ducts. By this finding, however, active clonorchiasis cannot be differentiated from cured infection. Some recent radiologic studies suggested specific findings of active clonorchiasis. Besides direct demonstration of worms, increased periductal echogenicity on sonography and periductal enhancement on dynamic contrast-enhanced CT or MR imaging possibly represent active clonorchiasis. Those images of the liver clonorchiasis are known to be correlated with worm burdens (EPG counts) in their frequency and also severity. The images of cholangiocarcinoma associated with clonorchiasis show both the tumor with obstruction images and diffuse dilatation of the peripheral intrahepatic bile ducts. Radiological images can be a good practical alternative diagnostic method of clonorchiasis.
Bile Ducts/parasitology/pathology ; *Cholangiography ; Clonorchiasis/*diagnosis/ultrasonography ; Humans

A study was carried out to figure the cases and to observe the endemic status of clonorchiasis and metagonimiasis in endemic areas in Korea. Total 13,373 inhabitants living in 40 villages along 7 main rivers and 9 small streams were subjected to stool examination. They were selected randomly among the riverside population. Their specimens were examined both by cellphane thick smear method and Stoll's egg countung technique. This study was performed during the period from May 1979 to April 1980. The results obtained are as follows: The egg positive rate of any kind of helminths was 58.7% out of 13,373 examned cases, and the egg positive rates by each helminth were; Clonorchis sinensis 21.5%, Metagonimus yokogaqai 4.8%, large type Metagonimus eggs 0.4%, Ascaris lumbricoides 22.9%, Trichuris trichiura 35.2%, hookworm 0.2%, Taenia sp. 0.5%, Hymenolepis nana 0.07%, Paragonimus westermani 2 cases, Fasciola sp. 4 cases, Echinostoma sp. 1 case and Hymenolepis diminuta 1 case respectively. Many endemic foci of clonorchiasis were revealed along the 7 major rivers. The egg positive rates of each river basin differed from each other significantly; Nagdonggang 40.2%, Yeongsangang 30.8%, Seomjingang 17.3%, Hangang 15.7%, Tamjingang 15.9%, Geumgang 12.0% and Mangyeonggang 8.0%. The cases of clonorchiasis were estimated in range 830,000 to 890,000 in riverside areas of the 7 rivers. By grading the infection intensity, 64.7% was in Grade I(EPG 0-900), 28.6% in Grade II (EPG 1000-9,900), 5.5% in Grade III (EPG 10,000-29,900) and 1.3% in Grade IV (EPG over 30,000). The proportion of the cases in Grade III and IV was 6.8% among positive cases. Therefore 60,000 cases at least were regarded to suffer from it clinically. Males of 30-60 years of age showed higher positive rate and heavier burden of infection. This makes clonorchiasis more important socially because the patients lose their social productivity. A few endemic foci of metagonimiasis were detected newly by egg detection; Samcheong 28.5% egg positive rate, Uljin 21.3%, Yeuongdeog 46.3%, Milyang 6.7%, Yeongil 9.2% and Geoje 18.2%. The mean EPG values were in range of 320-7, 120 by the focus. The egg positive rate and proportion of EPG Grade varied greatly by the area, and mean proportion of the positive cases were 69.7% in Grade I, 24.1% in Grade II, 5.0% in Grade III and 1.2% in Grade IV. Males of 30-60 years were infected in higher rate also. The large sized eggs of Metagonimus were found also in upper basin of Hangang and Geumgang mainly. They were regarded as eggs of M. takahashii which is mediated by the cyprinid fishes. Its significance should be studied further. Clonorchiasis and metagonimiasis should be realized as important public health problems in Korea by their wide distribution, high prevalence rate and heavy infection intensity. Comprehensive measures against them are needed urgently.
parasitology-helminth-trematoda ; clonorchiasis ; metagonimiasis ; Clonorchisis sinensis ; Metagonimus yokogawai ; epidemiology

The sensitivity and specificity of crude and affinity-purified antigens of Clonorchis sinensis obtained from the infected rabbits were studied. Stage-specific antigenic proteins from the eggs, metacercariae and adult worms were characterized by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunosorbent assay (ELISA) The results were as follows: The antibody-binding antigen (ABA) purified from whole worm crude antigen (WWA) by CNBr-activated Sepharose 4B affinity chromatography made 4 specific bands against rabbit anti-sera on Ouchterlony gel diffusion plate, while WWA made 7 bands. Major WWA protein bands by SDS-PAGE were found at 16,300-18,500 and 28,000-29,000 daltons, while major ABA protein bands were at 18,000-21,000 and 29,000-31,000 daltons. The reactivity of ABA with rabbit anti-sera in ELISA was remarkably less sensitive than that of WWA. Molecular weights of egg antigen (EGA), metacercarial antigen (MEA) and adult worm antigen (WWA) of C. sinensis ranged from 15,000-200,000 daltons, 15,000-100,000 daltons and 11,000-80,000 daltons, respectively. Major WWA proteins consisted mainly of polypeptide bands of low molecular weight, less than 31,000 daltons, while those of EGA and MEA consisted of higher molecular weights than 30,000 daltons. The ELISA reactivities of WWA to rabbit anti-sera were remarkably greater than those of MEA. EGA showed negative reaction throughout the experiments. WWA showed higher optical density (O.D.) than 1.0, when reacted with rabbit anti-sera obtained at 4-6 weeks after the infection. In the rabbit anti-sera later than 12 weeks after the infection, the O.D. reacting with WWA showed a plateau without variation. MEA showed relatively low O.D. values (<0.6), when reacted with anti-sera from lightly infected groups throughout the experiments, although there were some weak positive cases (O.D.>0.6) in heavily infected groups. MEA reacted with rabbit anti-sera showed negative results on Ouchterlony gel diffusion plates. Summarizing the above results, it is suggested that the whole worm antigen prepared from the adult worms of C. sinensis is most highly antigenic. However, this antigen might reveal cross reactions with other trematodes such as Paragonimus westermani, therefore, purification of antigenic proteins from the crude antigen is essential to increase the sensitivity and specificity for the immunodiagnosis of clonorchiasis.
parasitology-helminth-trematoda ; Clonorchis sinensis ; clonorchiasis ; rabbit ; immunology ; diagnosis ; antigen

The pond smelt Hypomesus olidus and minnow Zacco platypus were collected from the Soyang and Daechung Lakes in January 2003, and their metacercarial infections was examined by the muscle compression and artificial digestion techniques. In the Soyang Lake, 161 metacercariae of Clonorchis sinensis (0.35 per fish) were harvested from 459 pond smelts examined. Also, 13 metacercariae of C. sinensis (0.43 per fish), 1 of Metagonimus sp., 4 of Echinostoma sp., 148 of Centrocestus armatus and 44 unidentified species were collected from 30 minnows. In the Daechung Lake, 369 metacercariae of C. sinensis (3.69 per fish) and 51 unidentified species were recovered from 100 pond smelts. The metacercariae of C. sinensis were fed to experimental rats, in which the adult flukes were identified. The pond smelts and minnows collected from the Soyang and Daechung Lakes were verified to be the second intermediate hosts and the sources of human C. sinensis infection.
Animals ; Clonorchiasis/parasitology/*veterinary ; Clonorchis sinensis/growth & development/*isolation & purification ; Cyprinidae/*parasitology ; Fish Diseases/parasitology ; Fresh Water ; Host-Parasite Relations ; Korea ; Osmeriformes/*parasitology ; Rats ; Rats, Sprague-Dawley