• Parasites, Hosts and Diseases
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• 제50권4호
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• pp.317-325
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• 2012

The prevalence of foodborne trematode (FBT) metacercariae was investigated in fish from 2 localities of northern Vietnam in 2004-2005. Freshwater fish (9 species) were collected from local markets in Hanoi City (n=76) and Nam Dinh Province (n=79), and were examined for FBT metacercariae using the artificial digestion technique. Adult flukes were obtained from hamsters experimentally infected with the metacercariae at day 8 post-infection. Three (Haplorchis pumilio, Centrocestus formosanus, and Procerovum varium) and 6 (Haplorchis taichui, H. pumilio, C. formosanus, P. varium, Stellantchasmus falcatus, and Heterophyopsis continua) species of FBT metacercariae were detected in the 2 regions, respectively. Overall, among the positive fish species, H. pumilio metacercariae were detected in 104 (80.0%) of 130 fish examined (metacercarial density per infected fish; 64.2). C. formosanus metacercariae were found in 37 (40.2%) of 92 fish (metacercarial density; 14.7). P. varium metacercariae were detected in 19 (63.3%) of 30 fish (Anabas testudineus and Mugil cephalus) (metacercarial density; 247.7). S. falcatus metacercariae were found in all 10 M. cephalus examined (metacercarial density; 84.4). H. continua metacercariae (2 in number) were detected in 1 fish of Coilia lindmani. Morphologic characteristics of the FBT metacercariae and their experimentally obtained adults were described. The results have demonstrated that various FBT species are prevalent in northen parts of Vietnam.

• Parasites, Hosts and Diseases
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• 제58권6호
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• pp.701-707
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• 2020

A survey was performed to investigate the infection status of zoonotic helminth larvae in fish from a local market of North Dagon District in Yangon City, Myanmar. A total of 486 fish in 13 species were collected 8 times from December 2015 to December 2019. All fish were transported under ice to a laboratory in Korea and examined for helminth larvae using artificial digestion method. Larval gnathostomes and metacercariae of more than 8 zoonotic trematode species, i.e., Opisthorchis viverrini, Haplorchis taichui, H. pumilio, H. yokogawai, Centrocestus spp., Stellantchasmus falcatus, Pygidiopsis cambodiensis, and Procerovum sp., were detected. Larval gnathostomes were found in 58 (16.0%) out of 362 fish of 6 species, with mean intensity of 2.8 per fish infected. Metacercariae of O. viverrini were detected in 10 (2.9%) out of 349 fish of 5 species, with mean intensity of 16.9 per fish infected. Metacercarial prevalences of 4 intestinal flukes, H. taichui, H. pumilio, H. yokogawai, and Centrocestus spp., were 16.8%, 26.0%, 12.5%, and 15.0% in the positive fish species, respectively, and mean metacercarial intensity was 63.3, 26.8, 86.2, and 8.7 per fish infected. Metacercariae of S. falcatus and P. cambodiensis were detected only from the mullet, Chelon macrolepis. Metacercariae of Procerovum sp. were found in Channa striata and Anabas testudineus. Collectively, it was confirmed that the fish were infected with gnathostome larvae and metacercariae of O. viverrini and intestinal flukes in Yangon City, Myanmar.

• Parasites, Hosts and Diseases
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• 제29권1호
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• pp.55-66
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• 1991

Heterophyidae과에 속하는 Matagenimus yokegawai, Metagonimus Miyata Type, M. takahashii, Heterophyes disbar, H. heterophyes, H. nocens, Heterophyepsis continua, Pygidiopsis summa, Stellanpchasmusfaltatus, Stittodora lari 등 총 21 Operational Taxonomic Unit(OTU)를 사용하여 수리분류학적 연구를 시도하였다. 형질은 절대 측정치가 아닌 상대적 비율을 주로 사용하였으며, 형질수는 26개를 사용하였다. 각 형질간의 유사도를 측정하여 상관계수를 계산한 후 Ward의 방법에 의한 집괴 분석 및 인자 분석을 수행하였다. 분석 결과 Metagonimus 속(genus) 그룹은 Metagonimus yokogawai, Metagonimus Miyata Type, M. takahashii 등 3개의 표현군으로 구분이 되었으며, Metagenimus Miyata Type은 M. takahashii 의 아종 수준으로 분류되었다. Heterophyes 속 그룹은 Heterophyes dispar, H. heterophyes, Jf. nocens 등 명확한 3개의 표현 군으로 구분되며, H. nocens는 H. heterophyes의 아종이 아닌 뚜렷한 종의 수준에서 분류됨을 나타내었다. 그 외의 종들도 역시 뚜렷한 표현 군으로 분류되었으며, 이로부터 흡충류에 있어서도 수리분류학적 방법에 의해 분류가 명화한 분류군의 한계를 규정하는데 많은 도움을 줄 수 있을 것으로 사료된다.

• Parasites, Hosts and Diseases
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• 제43권3호
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• pp.93-100
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• 2005

The present study was performed to investigate the infection status with helminth in a group of feral cats in Korea. More than 29 helminth species including adults or eggs were detected in visceral and fecal samples of the examined cats. Among these were a host of nematodes, including toxocarids, Ancylostoma sp. and the larva of Anisakis simplex; trematodes, including Clonorchis sinensis, Paragonimus westermani, Eurytrema pancreaticum, Pharyngostomum cordatum, Metagonimus spp., Heterophyes nocens, Pygidiopsis summa, Heterophyopsis continua, Stictodora fuscata, Stictodora lari, Acanthotrema felis, Stellantchasmus falcatus, Centrocestus armatus, Procerovum varium, Cryptocotyle sp., Echinostoma revolutum, Echinostoma hortense, Echinochasmus japonicus, Stephanoprora sp., Plagiorchis muris, Neodiplostomum sp. and diplostomulum. We also detected a variety of cestodes, including Spirometra erinacei, Taenia taeniaeformis and unidentified species of tapeworm. We also found examples of the acanthocephalan, Bolbosoma sp. In our assessment of the stools, we detected at least 12 species of helminth eggs. These findings confirmed that feral cats in Korea are infected with a variety of helminth parasite species. Furthermore, among the helminths detected, E. pancreaticum, S. fuscata, S. lari, A. felis, S. falcatus, C. armatus, P. varium, Cryptocotyle sp., E. revolutum, E. japonicus, Stephanoprora sp., P. muris, Neodiplostomum sp. and Bolbosoma sp. represent helminth fauna which have not been reported previously in feral cats in the Republic of Korea.

• Parasites, Hosts and Diseases
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• 제50권3호
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• pp.207-213
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• 2012

The egg morphology of minute intestinal flukes (MIF) that can occur as human infections in the Republic of Korea, i.e., Metagonimus yokogawai, M. miyatai, M. takahashii, Heterophyes nocens, Heterophyopsis continua, Stellantchasmus falcatus, Stictodora fuscata, Pygidiopsis summa, and Gymnophalloides seoi, was studied in comparison with Clonorchis sinensis. The adult worms were obtained from residents of endemic areas, and their intrauterine eggs were studied and measured using light microscopy; the length, width, length-width ratio (LWR), and Faust-Meleney index (FMI). Several specimens were processed for scanning electron microscopy (SEM), and before gold-coating, the uterine portion of each fluke was etched with a sharp pin in order to expose the eggs. The MIF eggs were ovoid, pyriform, or elliptical with a size range of $21-35{\times}12-21{\mu}m$. S. fuscata eggs revealed the highest FMI (largest in the area) and lowest LWR, whereas P. summa eggs showed the lowest FMI and medium LWR. SEM revealed that G. seoi and S. fuscata had remarkably clean shell surface lacking the muskmelon-like structure which is prominent in C. sinensis eggs. In Metagonimus spp., H. continua, H. nocens, and S. falcatus eggs, minute surface ridges were recognizable though less prominent compared with C. sinensis. On the surface of P. summa eggs, thread-like curly structures were characteristically seen. The results revealed that important differential keys for MIF eggs include the length, width, area (FMI), shape of the eggs, and the extent of the muskmelon-like structure or ridges on their shell surface and operculum.

• Parasites, Hosts and Diseases
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• 제53권2호
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• pp.209-213
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• 2015

The present study was performed to survey the infection status of zoonotic intestinal trematode (ZIT) in stray cats from 5 major riverside areas in the Republic of Korea. Total 400 stray cats were captured with live-traps in riverside areas of Seomjingang ('gang' means river) (203 cats) from June to October 2010, and of Yeongsangang (41), Nakdonggang (57), Geumgang (38), and Hangang (61 cats) from June to October 2011, respectively. Small intestines resected from cats were opened with a pair of scissors in a beaker with 0.85% saline and examined with naked eyes and under a stereomicroscope. More than 16 ZIT species were detected in 188 (92.6%) cats from Seomjingang areas, and the number of worms recovered was 111 per cat infected. In cats from riverside areas of Yeongsangang, Nakdonggang, Geumgang, and Hangang, more than 9, 8, 3, and 5 ZIT species were recovered, and the worm burdens were 13, 42, 11, and 56 specimens per infected cat, respectively. As the members of family Heterophyidae, more than 10 species, i.e., Metagonimus spp., Pygidiopsis summa, Heterophyes nocens, Stellantchasmus falcatus, Heterophyopsis continua, Acanthotrema felis, Centrocestus armatus, Procerovum varium, Cryptocotyle concava, and Stictodora lari, were recovered. More than 5 species of echinostomes, i.e., Echinostoma hortense, Echinochasmus japonicus, Echinochasmus sp., Echinoparyphium sp., and unidentified larval echinostomes, were collected. Plagiorchis spp. were detected in cats from areas of Seomjingang and Yeongsangang. From the above results, it has been confirmed that stray cats in 5 major riverside areas of Korea are highly infected with various species of ZITs.

• Parasites, Hosts and Diseases
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• 제58권1호
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• pp.27-35
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• 2020

This study aimed to investigate metacercarial infections in the wrestling halfbeak, Dermogenys pusilla, collected from Bangkok metropolitan region of Thailand. A total of 4,501 fish from 78 study sites were commonly examined with muscle compression and digestion methods (only head part of fish) during September 2017 to July 2018. The overall prevalence of metacercarial infection was 86.1% (3,876/4,501 individuals), and the mean intensity was 48.9 metacercariae per fish infected. Four species, i.e., Posthodiplostomum sp., Stellantchasmus falcatus, Cyathocotylidae fam. sp., and Centrocestus formosanus, of digenetic trematode metacercariae (DTM) were detected. The prevalences were 65.8%, 52.0%, 2.1%, and 1.2%, respectively and their mean intensities were 23.1, 51.6, 1.4, and 3.2 per fish infected, respectively. The seasonal prevalences were 81.0% in winter, 87.8% in summer and 87.4% in rainy, and the mean intensities were 38.9, 46.6, and 55.2 metacercariae per fish infected, respectively. Conclusively, it was confirmed that the wrestling halfbeak play the role of second intermediate hosts of 4 species of digenetic trematodes including S. falcatus and Posthodiplostomum sp. in Bangkok metropolitan region. And then the metacercariae of C. formosanus and Cyathocotylidae fam. sp. are to be first found in the wrestling halfbeak by this study.

• Parasites, Hosts and Diseases
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• 제51권1호
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• pp.99-106
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• 2013

In 2005, we reported the infection status of 438 stray cats with various species of intestinal helminths, including nematodes (4 species), trematodes (23 species), and cestodes (5 species) in the Republic of Korea. However, morphologic details of each helminth species have not been provided. In the present study, we intended to describe morphologic details of 13 trematode species which were either new fauna of cats (10 species) or new fauna of not only cats but also all animal hosts (3 species). The worms were fixed in 10% neutral buffered formalin under a cover slip pressure, stained with Semichon's acetocarmine, and then observed using a light microscope equipped with a micrometer. The 13 subjected species included members of the Heterophyidae (Stellantchasmus falcatus, Stictodora fuscata, Stictodora lari, Centrocestus armatus, Procerovum varium, and Cryptocotyle concava), Echinostomatidae (Echinostoma hortense, Echinostoma revolutum, Echinochasmus japonicus, and Stephanoprora sp.), Diplostomidae (Neodiplostomum seoulense), Plagiorchiidae (Plagiorchis muris), and Dicrocoeliidae (Eurytrema pancreaticum). By the present study, Cryptocotyle sp. and Neodiplostomum sp. recored in our previous study were identified as C. concava and N. seoulense, respectively. Three species, P. varium, C. concava, and Stephanoprora sp., are new trematode fauna in Korea.

• Parasites, Hosts and Diseases
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• 제22권2호
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• pp.171-180
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• 1984

우리 나라의 인체기생 이형흡충류(요꼬가와흡충, Heterophyes heterophyes nocens, Stellantchasmus falcatus, Heterophyopsis continua, Pygidiopsis summa) 및 간흡충 충란의.비교형태학적 특징을 관찰함으로써 대편검사에 의한 이들의 진단에 도움이 되도록 하고자 이 연구를 실시하였다. 충란은 감염자를 치료하여 얻은 각 충체의 자궁말단으로부터 분리한 것을 사용하였고 전체적인 외형 및 형태는 물론 길이, 폭 및 길이1폭의 비를 구하여 종별로 비교검토하였다. 결과를 요약하면 다음과 같다. 1. 간흡충 충란은 전단부가 오목한 약간 긴 난원형이며, 길이 $25.3-33.2{\mu}m$(평균 $28.3{\mu}m$), 폭 14.2-17.4 (15.9)${\mu}m$, 길이1폭의 비가 1.60~2.00(1.78)이었다. 이들은 난각에 주름(wrinkling)이 뚜렷한 점에서 관찰한 모든 이형흡충류 충란과 구별되었다. 2. P. summa의 충란은 난원형 또는 서양배 모양이며 관찰한 충란중 가장 작은 점이 특징이었고, 길이 $19.8~22.9(21.6){\;}{\mu}m$, 폭 $11.1~13.4(12.1){\mu}m$, 3 비는 1.63~1.99(1.78)이었다. 3. S. falcatus의 충란은 장란소형이며 가장 길쭉한 형태인 것이 특징이었고, 길이 $25.3~29.2(27,2){\;}{\mu}m$, 폭 $11.1~13.4(12.5){\mu}m$, 비는 2.00~2.57(2.17)이었다. 요꼬가와흡충 충란은 유타원형 또는 타원형이며 양단이 둥근 편이었고, 길이 $26.9~31.6(28.5){\mu}m$, 폭 $14.2~18.2(16.8){\mu}m$, 비는 1.48~2.11 (1.70)이 었다. 5. H. continua 충란은 난형이었고 요꼬가와흡충란이나 H. h. nocens 충란과 비슷한 경우도 많으나 충란의 길이에 비해서 폭이 가장 크고 최대폭이 충란 후반부에 있는 점이 특징적이었으며, 길이 $23.7~27.7(25.0){\mu}m$, 폭 $15.8~15.9(16.4){\mu}m$, 비는 1.33~1.75(1.53)이었다. 6. H. h. nocens의 충란은 유타도형 또는 난원형이나 요꼬가와흡충보다는 다소 덜 팽대되어 있고 양단이 다소 뾰족한 감을 주는 것이 특징이며, 길이 $23.7~29.2(25.7){\mu}m$, 폭 $14.2~15.8(15.4)){\mu}m$, 비는 1.50~2.06(1.67)이었다. 이상의 결과로 볼 때 5종 이형흡충류 및 간흡충 충란은 형태학적으로 서로 감별할 수 있을 것으로 생각되나 많은 수의 충란에 대한 세밀한 관찰과 계측이 요구된다는 것을 알 수 있었다.

• Parasites, Hosts and Diseases
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• 제36권3호
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• pp.155-162
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• 1998

우리 나라 일부 해안 지역의 장내 기생충 감염현황을 파악하기 위해 전북 부안군 주민 153명 및 경남 사천군 주민 138명의 대변을 수집하여 셀로판 후층 도말법 및 포르말린-에테르 침전법을 실 시하였다. 전북 부안군의 기생충 감염률은 21.5% (33/153명)이었으며, 감염 기생충별 양성률은 이형흡충류 17.6%, 간흡충 2.6%, 회충 0.7%, 람블편모충 2.6%, 대장아메바 0.7% 및 작은와 포자충 0.75이었다. 경남 사천군의 기생충 감염률은 39.1% (54/138명)로서 이형흡충류 18.8%, 간흡충 12.3%, 편충 2.2%, 람블편모충 2.2%, 대장아메바 5.0%, 이질아메바 0.7%, 왜소아메바 3.6% 및 작은와포자충 4.3%의 양성률을 보였다. 부안군에서 이형흡충란 양성자 22 명으로부터 회수한 충체는 유해이형흡충이 총 3,284마리 (평균 149.3마리)였으며 표주박이형흡 충, 수세미이형홉충, 요코가와흡충, 미야타흡충, 자루이형흡충, 참굴큰입흡충, 긴이형흡충 및 Aconthopowphium kurogamo등이 중복 감염되어 있었다. 사천군에서 이형흡충란 양성자 중 6명으로부터 회수한 충체는 요코가와흡충이 총 3,007마리 (평균 501.2마리)였으며 유해이형흡충, 수 세미이형흡충, 긴이형흡충, 갈매기이형흡충 등의 이형흡충류가 중복감염되어 있었다. 이상의 결과로 우리 나라 남해 및 서해안 지역 주민들에서 담수어 또는 반염수어의 생식 습관으로 장내 흡충, 특히 이형흡충류의 유행이 지속되고 있음을 확인하였다.