• Parasites, Hosts and Diseases
• /
• v.60 no.2
• /
• pp.79-96
• /
• 2022

The infection nature of Clonorchis sinensis metacercariae (CsMc) in freshwater fish hosts is closely related to the transmission of human clonorchiasis. This article reviewed the infection characteristics of CsMc in freshwater fish in the Republic of Korea (Korea). The status of CsMc infection was examined in a total of 17,792 cyprinid fish of 49 species in 9 water systems, which included Hantan-/Imjin-gang, Han-gang, Geum-gang, Mangyeong-gang, Yeongsan-gang, Tamjin-gang, Seomjin-gang, Nakdong-gang, and streams in the east coastal areas from 2010 to 2020. The infection status of CsMc was examined according to cyprinid fish species and water systems, after which analyzed by endemicity and susceptibility index. The high endemicity was shown in the cyprinid fish from 3 regions (6.1%) in the upper reaches of Nakdong-gang, such as Banbyeon-cheon (stream), Yongjeon-cheon, and Wi-cheon. The moderate levels were observed in fishes from 8 regions (16.3%), and low endemicity was shown in fishes from 20 regions (40.8%). No CsMc were detected in fish from 18 regions (36.7%). The susceptibility of CsMc in index fish, Puntungia herzi, was found to be a reliable index without examination of other fish species. CsMc infection rates were closely related to subfamily groups in the cyprinid fish hosts in a highly endemic area. In Korea, a total of 58 fish species in 10 families has been listed as the second intermediate hosts for C. sinensis. This review provides several novel features of CsMc infection and clarifies the species of second intermediate freshwater fish host in Korea.

• Parasites, Hosts and Diseases
• /
• v.21 no.2
• /
• pp.116-186
• /
• 1983

An epidemiological study on Clonorchis sinensis infection along the Nam-river (total length ; 186km) flowing in Gyeongsang-nam-do, southern part of Korea, was carried out. Formalin-ether concentration technique and Stoll's egg counting method were employed to figure out the prevalence of C. sinensis infection. For the detection of cercariae from Parafossarulus sp., the snail host of C. sinensis, each snail was placed in aerated tap water, and examined for expelled cercariae. For observing the metacercariae the fresh water fish favorably eaten in raw conditions wore prepared by means of pressing the muscles between two slide glasses and/or by digesting them with artificial gastric juice. The fresh water fish were fed to the rabbits to get the worms and to identify the morphology of adult C. sinensis. The results are summarized as follows: 1. Overall Prevalence of C. sinensis infection was 38.75 from 5,291 examinees; 44.15 (1,408 out of 3,196) in male and 30.4% (637 out of 2,095) in female. 2. The prevalence rates were 42.0% at the upper stream, 41.2% around the vicinity of Jinyanglake, 34.2% at Jinju city, 34.2% at middle stream and 40.3% at down stream regions, respectively. 3. By age, the highest positive rate (53.4∼54.3%) was observed in 30 to 59 years of age. In this age group, the rate in males was 59.7∼62.2%, and in females 42.2∼44.4%, In the age group of less than 19 years it was 7.5∼20.9%. 4. By social strata, the positive rate was 16.5% in the primary school children, 22.6% in school students, 46.2% in teachers and local officers and 49.6% in the general inhabitants. 5. The quantitative examinations with the stool collected from clonorchiasis cases revealed that the light infection (less than 4,000/EPG) was 53.6%, moderate infection (4,001∼10,000 /EPG) 30.3% and heavy infection (more than 10,001/EPG) 16.1%, respectively. More than half of total cases examined were light infection, and 73.2% of female examinees were lightly infected with this cuke. 6. The average value of EPG was 4,963 (male, 6,057; female, 2,557 and the highest value was obtained from the age group of 30 to 59 years (5,240∼6,454). 7. The prevalence of Metagonimus yokogawai infection in humans was 5.5%, and 89.8% of metagonimiasis cases wore double-infected arith C. sinensis. The highest prevalence rate was observed in Jinju city (11.2%). 8. Total of 5,005 Parafossarulus sp., the snail intermediate host of C. sinensis, were examined for the detection of cercariae. The cercarial expulsion rate was 0.34%, and the snails collected in Jin-yang-lake side and in the down stream expelled mainly the cercariae of C, sinensis. 9. About 788 cercariaejday (range: 127∼1,503) were expelled daily from a snail naturally infected with C. sinensis. The snails which released more than 1,000 cercariae/day were 30.8% out of total collected. A snail uniquely released 5,840 cercariae/day in this study. 10. The other trematode cercariae besides C. sinensis were also detected, and the rates out of total snails were the cercariae of Losogenes liberum 6.71%, Cyathocotyle orientalis 0.26%, Notocotylus attenuatus 2.52% and Mucobucaris 0.54%, 11. Ten out of 18 species of fresh water fish caught along the river harbored the metacercariae of C, sinensis. The highest rate of metacercarial infection in fish was detected in Pseudorasbora larva (85.9%). The fish mainly eaten by the inhabitants along the Nam-river, and the metacercarial infection rates were: Zacco platypus 8.0%, Hemibarbus sp. 18.2∼26.7%, Gnathepcgcn sp. 37.5%, Ischikauia steenackeri 42.9% and Pseudogobio esocinus 16.7%. 12. Out of 36 P. larva, the number of metacercariae were about 109 (ranEe; 18∼446) per fish and 27 per gram of flesh. The fish caught in spring harbored the highest number of metacercariae. As indicated above, the prevalence of C. sinensis infection in the inhabitants residing around the Nam-river was relatively high. The farther toward the upper stream areas, the higher was the positive rate of C. sinensis infection, and most of clonorchiasis cases were lightly infected. The snail hosts of C. sinensis distributed all around the Nam-river. Several species of freshwater fish were infected with the metacercariae of C. sinensis and the infection rates were relatively high. To prevent C. sinensis infection in the endemic areas, the effective health education system is suggested as a control measure, although mass treatment is also expected to be useful, using chemotherapeutic agents such as "praziquantel", a recently developed anthelminthic for C. sinensis inftraction.

• Parasites, Hosts and Diseases
• /
• v.26 no.2
• /
• pp.73-86
• /
• 1988

The sensitivity and specificity of crude and affinity-purified antigens of Clcnorchis 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 astray (ELISA). The results were as follows: 1. The antibody.binding antigen (ABA) purified from whole worm crude antigen (IVWA) by CNBr-activated Sepharose 4B affinity chromatography made :l specific bands against rabbit antisera 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. 2. 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 T.eights than 30, 000 daltons. 3. 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 witll WWA showed a plateau without variation. MEA shoT.ed relatively low O.D. values (<0.6), when reacted with anti-sera from lightly in(ected groups throughout the experiments, althougll there were some wealth positive cases (O.D.>0.6) ill 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 18 increase the sensitivity and specificity for the immuncdiagnosis of clonorchiasis.

• Parasites, Hosts and Diseases
• /
• v.21 no.2
• /
• pp.193-204
• /
• 1983

The Jinyang Lake is dammed up Nam River, and surrounded by Jinju city and four counties; Jinyang, Sanchong, Hading, and Sachon in kyongsang-Nam-Bo, Korea. The areas around this man-made lake have been known as an endemic focus of clonorchiasis in Korea. The present study was first aimed to know the distribution of freshwater mollusks including medically important snails, and larval trematodes shed from Parafossarulus manchouricus and Semisulcospira libertina. In addition to above studies, water analyses in each snail habitat were carried out in order to figure out a part of their environmental factors. This malaco-ecological survey was done at the sirs areas around upper, middle and lower parts of the lake for 4 months, August-November, 1983. Total nine species of freshwater mollusks were collected throughout the study: 4 species of gastropods: Semisulcospira libertina, Cipangopaludina chinensis, Parafossarulus manchouricus and Radin auricularia, and 5 species of bit.alves; Unio dcuglasiae, Ancdonta woodiana, Lamprotula gottschei, Corbicula yuminea and Limncperma lucustris. Out of nine species of freshwater mollusks, three species of gastropods; S. Zibertina, p. manchouricus and R. auricularia were medically important in terms of the transmission of digenetic trematodes to humans. P. manchouricus and R. auricularia were mainly collected from the shallow ponds and the irrigation channels with the muddy basin, but S. libertine and the bivalves were only collected from the stream of Nam River where the gravels and rocks were dominant. The levels of dissolved oxygen (D.O.) and biochemical oxygen demand \(B.O.D._5)\ of the water specimens sampled from the study areas ranged from 6.0 to 9.6 ppm and from 0.4 to 1.6 ppm respectively. As a result, it is considered that water system around the Jinyang Lake might be relatively clean without any heavy pollution of aquatic microorganisms and organic materials during the period of this study. On the other hand, eight metalic constituents from the water samples were also assayed, and all metalic ions detected were remarkably low below the legal criteria. However, calcium ion in the water samples from the habitats of P. manchouricus was considerably higher than others. Infection rates of digenetic trematodes in the snails were 6.9% in P. manchouricus and 4.8% in S. libertine, respectively. P. manchouricus snails harboring with thc cercariae of Clonorchis sinensis were only 0.14% among the snails examined, and other trematode cercariae except cercaria of C. sinensis were: furcocercus cercariae, cercaria of Loxogenes liberum type I and II. S. libertine snails parasitized with the cercariae of Metagonimus yokogawai were 1, 5% out of the snails examined, and no cercaria of Paragonimus westermani was found in S. libertine snails in the present study. Digenetic trematode cercariae other than M. yokogawai observed in S. libertina snails were: Cercaria yoshidae (B type) , Cercaria cristata, Cercaria innominatum, Cercaria of Centrocestus formosanus and Cercaria nipponensis.

• Parasites, Hosts and Diseases
• /
• v.32 no.1
• /
• pp.35-42
• /
• 1994

This study was designed to evaluate the humoral immune reactions in clonorchiasis before and after praziquantel treatment. Rabbits were infected with 150 or 450 metacercariae, treated on 4 and 8111 months after infection, and observed for 13 months of posttreatment. Infection controls were maintained for 22 months. Antigen was the metabolic product of worms incubated in physiologic saline. The immune reactions of anti-clonorchis IgG were observed using SDS-PAGE/immunoblot. During the Infection and Posttreatment, the antigenic Proteins of 66, 63, 54, 52, 50,47,42, 40, 38, 34,33,30, 27, 25, 23, 20, 19, 18, 17, 16, 15, 14, 13, 12.5 and 11.5 kDa were detected. Of them, 33,27, 13, and 12.5-kDa antigens were highly antigenic and observed predominently in infection controls. After the treatment, 13 and 12.5-kDa antigens faded in 6 months after the second treatment, but 33 and 27-kDa antigens were detected until 13 months of posttreatment. The results clearly demonstrate that 13 and 12.5-kDa antigens represent attenuated host immune reactions by praziquantel treatment. As the 12.5-kDa antigen had a large amount of protein in SDS-PAGE, it was designated as'K2-Ag'of C. sinenis.

• The Korean Journal of Pharmacology
• /
• v.12 no.2 s.20
• /
• pp.51-59
• /
• 1976

Methylene bis (3, 4, 6-trichlorophenoxy acetic acid) 'MTPA' has been developed for the purpose of treatment of clonorchiasis. It has been rpeorted that, in patients treated with MTPA, the flukes in the liver were killed, elevated serum bilirubin returned to normal and the patients´ general condition was improved. However it took $1{\sim}4 $ weeks to obtain sufficient therapeutic effects. In rabbits, excretion of bilirubin in the bile was increased by the MTPA, and this action was enhanced by a combination of deoxycholic acid with MTPA. This study was designed as a part of a series to increase the therapeutic effect of MTPA, by observing the relation of the blood level of MTPA with the excretion of MTPA in the bile, and the excretion of MTPA with bilirubin excretion in the bile caused by the injection of MTPA alone or in combination with deoxycholic acid. $^{14}C-labeled$ MTPA alone or with deoxycholic acid were injected into the ear veins of rabbits. The amout of bile, MTPA and bilirubin in the bile and the blood level of MTPA were measured. The results obtained were as follows: 1. The amount of excreted bile was decreased gradually as the time elapsed in both groups, that is groups injected with MTPA alone and with deoxycholic acid, without any significant difference between either group. 2. The largest amount of MTPA excretion in the early stage of the MTPA excretion in both groups, but deoxycholic acid caused an increase in blood level of MTPA whereas biliary excretion of MTPA decreased, especially in the early stage after drug injection. 3. The significant increment of bilirubin excretion began within an hour and it reached peak level in $2{\sim}2\frac{1}{2}$ hours after drug injection in both groups, but the amount of excreted bilirubin was larger in the combined group. The above results suggest that deoxycholic acid interferes with the biliary excretion of MTPA, and that there is no close relation between the increased excretion of MTPA and bilirubin excretion. But there is a close relation between blood level or tissue concentration of MTPA and bilirubin excretion. Concerning the influence of deoxycholic acid on the therapeutic effect of MTPA, deoxycholic acid would enhance the effect of MTPA, if the parasites take the drug from the blood, but diminish its effectiveness if they take the drug from the bile.

• The Korean Journal of Pharmacology
• /
• v.2 no.2
• /
• pp.3-22
• /
• 1966

An experimental study was done on rabbits to observe the effects of several anticlonorchial drugs on the pathology of the liver infested with Clonorchis sinensis. After two months of infestation with Clonorchis sinensis by giving $400{\sim}500$ metacercariae by mouth, hexachlorophene, chloroquine 2,2' methylenebis (3,4,6 trichlorophenoxy acetic acid) and Hetol were administered orally and follow up macro-and microscopic studies of the liver pathology were done in 2 to 3 days, one month, 2 months and 3 months after the completion of medications. The results obtained in this study are as follows: 1. In both groups which were administered hexachlorophene piperazine 20mg/kg for seven days or 8mg/kg for 18 days, the macroscopic findings of the liver after 3 months revealed only minimal changes of the color and consistency The histopathological findings were the reduction of fibrosis, pseudolobulation, proliferation and adenomatous hyperplasia of bile ducts, and regeneration of liver parenchyma. 2. In groups which were administered chloroquine phosphate 20mg/kg for 18 days or 40mg/kg for 5 days, and also in groups which were administered dithiazanine iodide 30mg/kg for 18 days or 60mg/kg for 5 days, no significant findings of recovery were observed either macroscopically or microscopically. 3. In the group which was given 20mg/kg of 2,2' methylenebis(3,4,6 trichlorophenoxy acetic acid) for 5 days, prominent healing of the damaged tissues was observed after 2 months, revealing the decrease of fibrous tissue, caliber of bile ducts and adenomatous hyperplasia of the epitherial cells of the bile ducts, and regenerationof liver parenchyma. 4. In the group which was given Hetol 200mg/kg for 5 days, swelling, congestion and eddish-brown discoloration of the liver were noted macroscopically after 3 days of completion of drug administration. Hemorrhage, congestion, necrosis and degeneration of the parenchyma were observed microscopically After 10 days, liver appeared almost normal macroscopically, but marked fat degeneration was noted microscopically. After 2 months, the liver was almost normal in gross appearence with only slight atrophy and also marked healing was observed microscopically, i. e. decrease of fibrous tissue and reduction of the previously enlarged bile duct and the regeneration of the liver parenchyma.

• Parasites, Hosts and Diseases
• /
• v.32 no.2
• /
• pp.93-100
• /
• 1994

In order to know the species and frequency of human parasitic infection diagnosed by biopsy, 149 cases (0.18%) of parasitic infection were reviewed, which were selected from 80,947 biopsied materials submitted for routine histopathological examination during a period of 10 years from 1980 to 1989 at Department of Pathology, Chonnam National University Hospital. They consisted of 112 cases of cysticercosis, 17 paragonimiasis, 7 clonorchiasis, 4 amebiasis, 1 sparganosis, 1 enterobiasis, 1 anisakiasis, and 1 fascioliasis respectively Based on morphological preservation of cysticercus, they could be divided into mild (20.2%), moderate (40.4%), and severe (39.4%) degeneration. Except 2 cases biopsied at the lungs, 15 cases of ectopic paragonimiasis were located at abdominal cavity (8 cases) and central nervous system (7 cases). One case of intrahepatic fascioliasis was observed. This is the 13th human fasciollasis reported in Korea. From the above results, the frequency of parasitic infections found in biopsied specimens was on the decrease as the year passed by, but biopsy is very useful diagnostic method on tissue parasites such as cystlcercosis and ectopic paragonimiasis.

• Parasites, Hosts and Diseases
• /
• v.22 no.2
• /
• pp.223-228
• /
• 1984

Seven cases of surgically proven sparganosis were serologically tested by means of microELISA for their specific IgG antibody levels. For that purpose, crude saline extract of spargana from snake, Natrix tigrina lateralis was prepared and used as antigen. The sparganosis sera were also tested with Paragonimus and Cysticercus antigens to observe the cross reactivity. A total of 71 sera from normal control, ectopic and pulmonary paragonimiasis, clonorchiasis, cysticerCOSIS and Taenia saginata cases were also included. Except for one case of old calcified infection, all of 6 human sparganosis showed higher serum levels of specific IgG antibody when the differential point of positive reaction was set at the absorbance value of 0.25 (the sensitivity being 85.7%). In control and other helminthic infections, all except 3 cases of T. saginata infection showed negative reaction to sparganum antigen (the specificity being 90.7%). None of sparganosis cases showed cress reactivity to Paragonimus and Cysticercus antigens. Undiluted cerebrospinal l1uid also showed high levels of antibody when central nervous system was invaded. The serologic diagnosis by means of micro ELISA could be a useful tool in epidemiological study of human sparganosis in susceptible population, as well as in individual diagnosis.

• Journal of Preventive Medicine and Public Health
• /
• v.21 no.2 s.24
• /
• pp.329-339
• /
• 1988

The study is carried out to investigate the effect of drinking and smoking for the activities of aspartate aminotransferase(AST, or GOT) and alanine aminotransferase(ALT or GPT), from December 25, 1986 to April 30, 1987. The male physical examinees for employment, 900 who had visited to the Taegu Medical Center were subjected. And the positive cases of HBs-Ag, Anti-HBs and skin test for Clonorchis sinensis were excluded. The general characters of drinking and smoking pattern were introduced by interview with questionnaire provided for. In drinking cases, the longer duration was significantly effected the higher rate of abnormality in AST and ALT level. But the amount and the frequency were not. It was not appeared effects by mackgulri which is a Korean traditional wine and small amount of beers. In smoking cases, also same pattern. The age was related in all cases. By the way, when the effect is related the positive results with other factors: HBs-Ag, Anti-HBs, skin test for Clonorchiasis and harmful occupational history, it is higher abnormal rate of AST and ALT in the duplicated cases with two factors or more. Particularly in HBs-Ag positive cases, those who had smoking was the highest in rate of abnormality, and drinking was the follows. In correlation matrix among seven factors; HBs-Ag, age, drinking amount, drinking period, drinking frequency, smoking amount and smoking period, correlation coefficient was significant between the abnormal rate and to with age, drinking period, smoking period, and smoking amount.