• Parasites, Hosts and Diseases
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• v.36 no.3
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• pp.155-162
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• 1998

Two endemic foci of heterophyid infections were discovered in coastal villages of Puan-gun. Chollabuk-do, and Sachon-gun. Kyongsangnam-do, Korea. Fecal examina- tions were performed on 153 inhabitants of Puan-gun and 138 of Sachon-gun, using cellophane thick smear and formalin-ether sedimentation technique. The helminth egg and/or protozoan cyst positive rate was 21.5% (33/153) in Puan-gun and 39.1% (54/138) in Sachon-gun. In Puan-fun, the egg Positive rate of heterophyids was the highest, 17.6%, and that of other parasites was 0.7-2.6% by parasite species. In Sachon-gun, that of heterophyids wa's 18.8%, followed by Clonorchis sinensis (12.3%). and other parasites (0.7-5.OBEI . Twenth-two (Puan-gun) and six (Sachon-gun) heterophyid egg Positive cases were treated loth praziquantel, and adult flukes were collected from their diarrheic stools. A total of 3,284 adult flukes of Heterophyes nocens was collected from all of the 22 patients treated in Puan-gun (3-778 individually) , and other trematodes were also collected from 2- 15 patients; Ftgidiopsis sumac, Stellcntchcsmus JcEcctus, Metogoninus Wokogaupci, M. miyntci, Stictodora Juscnta, Heterophwopsis continua, Acnnthopcrwphium kurognmo, and GWmnophaELoines seoi. In Sachon-gun, M. yokognwci (3,007 specimens), H. nocens (120), aud S. falcatus (46) were collected from 5 of 6 treated patients, and H. continuo and 5. tan each from one patient. The present study revealed that heterophyid flukes, especially If. nocens and M. Wokofowai, are prevalent in the southern and western coastal areas of Korea where fresh and/or brackish water fishes are popularly eaten raw.

• Parasites, Hosts and Diseases
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• v.35 no.4
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• pp.233-238
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• 1997

A small coastal village of Muan-gun, Chollanam-do, was surveyed for intesti- nal fluke infections, especially heterophyids such as Heterophwes nocens and Ftsiniopsis summc by fecal examination on 108 inhabitants. The egg Positive rate of heterophyids was very high. 75.0%, and that of other parasites was comparatively low.0.9-3.7% by parasite species . After treatment of 20 patients showing high E. P. G. with praziquantel and purging with Mgs04, total 3,864 specimens of H. nocens were collected from the diarrheic stools of all the patients treated (3-1,338 individuallyl and total 703 p. summc were harvested from 18 patients (1-170 individually), together loth several other species of flukes. Other flukes included Stictodora jlscotn (164 specimens from 4 patients), Heterophwopsis continuo (2 from 2 patients), and Gwmnophalloides seoi (4 from 3 patients). From this study, the sutra- veyed coastal area of Muan-gun, Chollanam-do was proven to be a new endemic focus of H. nocens and p. summa. The occurrence of a few infected cases surf:mists that this area should also be a low-grade endemic area of S. Juscctc, H. continuo, and G. seoi.

• Biomedical Science Letters
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• v.18 no.3
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• pp.254-259
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• 2012

Infections involving Echinostoma hortense (E. hortense) are considered to more severe than infections caused by other heterophyids. Although parasite expulsion by host immune responses attenuates the symptoms of infection, the detailed mechanisms of the host immune response need to be determined, especially in local immune responses involving cytokine and immunoglobulin expressions. We infected BALB/c mice with E. hortense and examined recovery rates together with expressions of multiple cytokines and immunoglobulins in the villi and crypts of the small intestine using immunohistochemistry. We observed a close correlation between worm expulsion rates and cytokine/immunoglobulin expressions in E. hortense infected mice. This study contributes to an understanding of the relationship between the immune response and parasite expulsion in hosts.

• Parasites, Hosts and Diseases
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• v.53 no.4
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• pp.439-445
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• 2015

A survey of intestinal helminths was undertaken in riparian people in Xieng Khouang Province, Lao PDR. Fecal specimens were collected from 643 people (289 males and 354 females) residing in 4 districts (Nonghet, Kham, Phoukout, and Pek) and were examined by the Kato-Katz technique. The overall helminth egg positive rate was 41.2%, and hookworms revealed the highest prevalence (32.7%) followed by Trichuris trichiura (7.3%) and Ascaris lumbricoides (5.6%). The positive rate for small trematode eggs (STE), which may include Opisthorchis viverrini, heterophyids, and lecithodendriids, was 4.4%. For recovery of adult helminths, 12 STE or nematode/cestode egg-positive people were treated with 40 mg/kg praziquantel and 15 mg/kg pyrantel pamoate, and then purged. Mixed infections with 2 Haplorchis species (H. pumilio and H. taichui), Centrocestus formosanus, Opisthorchis viverrini, a species of cestode (Taenia saginata), and several species of nematodes including hookworms and Enterobius vermicularis were detected. The worm load for trematodes was the highest for H. pumilio with an average of 283.5 specimens per infected person followed by C. formosanus, H. taichui, and O. viverrini. The worm load for nematodes was the highest for hookworms (21.5/infected case) followed by E. vermicularis (3.2/infected case). The results revealed that the surveyed areas of Xieng Khouang Province, Lao PDR are endemic areas of various species of intestinal helminths. The STE found in the surveyed population were verified to be those of heterophyids, particularly H. pumilio.

• Parasites, Hosts and Diseases
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• v.26 no.2
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• pp.127-132
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• 1988

Two adult specimens of heterophyid cuke, which belong to the genus Stictodora, were collected from the stool of a 24-year old man after chemotherapy. The nukes were morphologically characterized by their small body siRe (0.90~0.98mm long and 0.38 mm wide) and peculiar structure of ventrogenital sac with armed gonotyl (with about 12~I5 spines) not enveloping genital pore. Species identification is deferred until more worms are obtained, although they closely resemble Stictadora fuscatum (Onji and Nishio, 1916). The Patient used to eat raw flesh of mullets and gobies, which are regarded as the infection source of Stictodora sp., together with 3 other kinds of heterophyids described elsewhere. This is the first record of human Stictodora infection in the literature.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.82-88
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• 1986

Two human cases of Heterophyes heterophyes and H. dispar infections were proven by the recovery of their adult worms. The cases were 38-year and 40-year old Korean workers who had been in Saudi Arabia for 4~6 years and returned home in 1983 or 1984 with gastrointestinal troubles. In Saudi Arabia they had eaten raw brackish water fishes such as the mullet. After the treatment with 10 mg/kg praziquantel and purgation with magnesium salt, a total of 19 specimens of H. heterophyes and 140 of H. dispar were collected. It is of interest that the worms persisted in a patient although he had been back in Korea for 14 months. This is the first report on imported heterophyiasis in Korea. Human infection by H. dispar is the first record in the literature.

• Parasites, Hosts and Diseases
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• v.47 no.3
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• pp.307-310
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• 2009

Fishborne trematode (FBT) metacercariae were investigated in yellowfin goby, Acanthogobius flavimanus, collected from Shinan-gun and Muan-gun, Jeollanam-do (province), Korea. All collected fishes were examined using the artificial digestion method. In all of 15 gobies from Aphae-myeon in Shinan-gun, metacercariae of Stictodora spp. (334 metacercariae/fish), Heterophyes nocens (153/fish), and Heterophyopsis continua (20/fish) were detected. In 2 of 14 gobies from Jido-myeon in Shinan-gun, 8 Echinostoma hortense metacercariae in total were detected. In 15 gobies from Haeje-myeon in Muan-gun, the metacercariae of H. continua were found in 100%, Stictodora spp. in 86.7%, and H. nocens in 6.7% of fish examined. The average numbers of metacercariae per infected fish were 23.3 (H. continua), 416.0 (Stictodora spp.), and 2.0(H. nocens), respectively. The metacercariae of E. hortense found in gobies were elliptical, with 150 ${\times}$ 138 ${\mu}m$, in average size, and had 27 collar spines on the head crown. The above results suggest that yellowfin gobies from 2 localities may be the potential infection sources of FBT. Moreover, it is proved for the first time that the yellowfin goby, A. flavimanus, acts as a second intermediate host for E. hortense.

• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.1-5
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• 2006

One coastal village in Haenam-gun and two in Yeongam-gun, Jeollanam-do were surveyed for intestinal parasite infections by fecal examination. The egg positive rates of Gymnophalloides seoi were high, $24.1\%$ (14/58) in Haenam-gun and $9.3\%$ (11/118) in Yeongam-gun. The egg positive rates of heterophyids, including Heterophyes nocens, and of Clonorchis sinensis were $10.3\%\;and\;6.9\%$ in Haenam-gun, and $14.4\%\;and\;8.5\%$ in Yeongam-gun, respectively. After praziquantel treatment and purgation, a total of 37,761 fluke specimens were recovered from 17 patients; 11 in Haenam-gun and 6 in Yeongam-gun. Gymnophalloides seoi was the most commonly recovered species, with 37,489 specimens in total (2,205 per person). Other recovered flukes included Heterophyes nocens, Stictodora fuscata, Heterophyopsis continua, Pygidiopsis sUmma, and undetermined species. These results indicate that the areas surveyed are new endemic foci of G. seoi.

• Parasites, Hosts and Diseases
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• v.32 no.3
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• pp.157-162
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• 1994

A highly endemic focus of human infection with Heterophves nocens (Heterophyidae) was discovered from a small coastal village of Shinan-gun, Chollanam-do, for the first time in Korea. Fecal examinations by cellophane thick smear and formalin- ether sedimentation techniques revealed 42.9% heterophyid egg Positive rate out of 98 inhabitants examined. It was difficult to confirm the species of heterophylds only by eggs. In order to collect the adult flukes, the egg Positive cases were treated with 10 mg/kg single dose of praziquantel and purged with magnesium sulfate, and the adult worms were collected from the diarrheic stools. From each of 18 cooperative patients 1 to 1,124 (total 4,730) H. nocens worms were recovered, together with a few to large numbers of heterophyids (Pvginiopsis summa, Stictonora juscatunl and for gymnophallids (Gvmopholloides stool) . It is speculated that H. nocen might be widely distributed along the southwestern coastal areas where the brackish water fish such as the mullets or gobies are popularly eaten raw.

• Parasites, Hosts and Diseases
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• v.46 no.3
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• pp.133-137
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• 2008

This study was performed to investigate prevalence of clonorchiasis among the inhabitants living in villages along the 4 major rivers, Nakdong-gang (= river), Seomjin-gang, Youngsan-gang, and Guem-gang in southern Korea. From January to December 2006, a total of 24,075 stool samples (1 sample per an inhabitant) were collected in 23 localities and examined by the formalin-ether sedimentation technique. Of the inhabitants examined, 3,441 (14.3%) were found to harbor various types of intestinal parasite eggs, cysts or larvae. Numbers of infected people were 2,661 (11.1%) for Clonorchis sinensis, 431 (1.8%) for heterophyids, 226 (0.9%) for Entamoeba spp., 57 (0.2%) for Giardia lamblia, 30 (0.1%) for Trichuris trichiura, and 18 (0.07%) for echinostomes. Prevalence rates of clonorchiasis according to the river basin were 17.1% in Nakdong-gang, 11.2% in Seomjin-gang, 5.5% in Youngsan-gang and 4.6% in Guem-gang. Of the 2,661 C. sinensis egg-positive cases, 57.7% was male. The present findings suggest that clonorchiasis is still highly prevalent among inhabitants in the riverside areas of southern Korea, and it is necessary to implement a systematic control program in the endemic areas.