The Hongcheon river system flows down through the Hongcheon area of Kangwon-do, and reaches to the Cheongpyeong Dam in Kyonggi-do. Stool specimens from the inhabitants residing along the Hongcheon river basin were examined to detect infection rate of Metagonimus sp., and the intermediate hosts were collected to detect larval stages. The results obtained were as follows: Thirty-nine (33 males and 6 females) out of 529 (314 males and 215 females) inhabitants were infected with Metagonimus sp., showing a total positive rate of 7.4 per cent. In eight areas surveyed, the specimens from Kulji-ri of Bukbang-myon at the middle part of the river showed the highest positive rate of 26.9 per cent (14 positives out of 52) (males; 38.2per cent). The specimens from Mogog-ri of Seo-myon at the downstream of the river showed a positive rate of 10.4 per cent (13 positives out of 125) (males;12.6 per cent). The positive rates in other regions were less than 10 per cent. The density of the first intermediate host, Semisulcospira sp., was the highest in Kulji-ri of Bukbang-myon (10-20 snails per m(2)), and the infection rate of Metagonimus cercariae in the snails was 10.7 per cent(13 positives out of 121 snails). The infection rate of Metagonimus metacercariae in Zacco platypus, the fresh water fish favorably eaten raw by the inhabitants, was 68.2 per cent (30 positives out of 44 fishes), and most metacercariae were detected under the scales (89.9 per cent). Adult flukes were obtained from the small intestine of a rat, 15 days after infection with the metacercariae obtained from Z. platypus. These adult flukes were identified to be the same srecies as those obtained from human hosts. By this survey, new endemic areas of Metagonimus infection were discovered along the Hongcheon river basin and the main source of infection was the fresh water fish, Z. platypus.
parasitology-helminth-termatoda ; Metagonimus sp. ; epidemiology ; metacercaria ; Zacco platypus

Recent patterns of infection with digenetic larval trematodes in fresh-water and brackish-water fish were studied in three locations of the river Taewha during the period from April to October 1988, and compared with the data reported previously in the same river. Of 16 species of fish examined, the encysted larvae of Cyathocotyle orientalis were found most frequently from 9 species of fresh-water fish. The metacercariae of Echinochasmus sp., Metacercaria hasegawai and Metagonimus yokogawai were found 8 species, those of Clonorchis sinensis from 7 species, and Exorchis oviformis and Metorchis orientalis from 5 species of fish. The infection rates of fish with C. sinensis metacercariae were not lower than those reported in 1980, wheres their intensity of infection was found lowered in 3 species, Coreobagrus brevicorpus, Gnathopogon atromaculatus, and Puntungia herzi. The infection rates of 3 species of fish with M. yokogawai metacercariae were lower than the results in 1982, while the rate was higher in 2 species, Zacco platypus, and Z. temmincki, and rather stationary in Plecoglossus altivelis. The intensity of infection in several species of fish appeared rather higher than in 1980. the encysted larvae of C. orientalis, Echinochasmus sp., E. oviformis and Metacercaria hasegawai showed variations in infection rates of fish in 1980 and in the present study. It was found that the rate of infection with digenetic larval trematodes in fresh-water fish was still relatively high in the river Taewha, and the metacercarial burden in the fish varied greatly by different fish in 1980 and in the present study.
parasitology-helminth-trematoda ; Cyathocotyle orientalis ; Echinochasmus sp. ; Metacercaria hasegawai ; Metagonimus yokogawai ; Clonorchis sinensis ; Exorchis oviformis ; Metorchis orientalis ; Coreobagrus brevicorpus ; Gnathopogon atromaculatus ; Puntungia herzi ; Zacco platypus ; Z. temmincki

The prevalences of the fluke belonging to genus Metagonimus have been reported along the upper stream of inhabitants by several workers since 1980, however the taxonomical problems of the fluke was not yet settled. The larval flukes; cercaria and metacercaria as well as their intermediate hosts, and adult were studied in order to identify the Metagonimus in the areas. The results obtained are summarized as follows: The snails, Semisulcospira globus were collected from the three different localities along the upper stream of the River. The cercariae were found from 125(7.2%) out of 1,730 snails by natural emerging method, and were identified into 5 species including Metagonimus sp. (3.7%), Pseudexorchis major(1.4%), Cercaria nipponensis (0.9), Cercaria incerta (0.6%) and Cercaria yoshidae(0.6%). Cercariae of Metagonimus species had four to five oral spines on its anterior of the first line. The cercariae of Metagonimus were experimentally exposed to goldfish. Infection rate was 22.9% out of 105 goldfish, and the encysted metacercariae were found in fins(86.7%) and on scales (13.7%) of the fishes, but not in their muscle, head or visceral organs. Seven species of fish were caught in the Daecheong reservoir and the upper stream. Infestations with metacercaria of Metagonimus were found 100% in Opsariichtys bidens and the parasitized numbers of the metacercariae were observed from 250 to 2,400 per fish. In the upper stream, Zacco temmincki, Z. platypus and Pseudogobio esocinus were infected 100% with the metacercaria, on the other hand, the fishes caught in the reservoir showed the lower infestation rates, and a few metacercariae found in the fishes Carassius carassius and Cyprinus carpio in the reservoir and the stream. The majority of metacercariae was detected only on the scales of fishes. In order to know the infectivity and the distribution patterns in the intestine of hosts, rats and dogs were infected with the metacercariae obtained from O. bidens and Z. platypus. In addition the metacercariae obtained from Z. temmincki, P. esocinus and goldfish were given to the rats. The recovery rates of the worms in the small intestine of dogs were higher (63.3-65.8%) than those of the rats (3.5-31.6%). The flukes were found mostly in the middle and the lower part of small tntestine of the rats and the dogs, but no worm was collected in the upper part of the intestine of rats. The size of adult flukes varied by the hosts. In the adult flukes, oral sucker was smaller than ventral sucker, and the right and left testes were located diagonally, the uterine tubules circled around the upper left testis. The average egg size was 29.1 x 17.7 micro-meter. According to the above results, the flukes belonging to genus Metagonimus distributed along the Geum River was concluded to be identical with Miyata type of M. yokogawai as that Saito had proposed.
parasitology-helminth-trematoda ; Metagonimus sp. ; epidemiology ; cercaria ; metacercaria ; Zacco temmincki ; Zacco platypus ; Pseudogobio esocinus ; Opsariichtys bidens ; Carassius carassius ; Cyprinus carpio

Total of 2,643 Korean soldiers were examined of their stool for parasitic infections by both cellophane thick smear and formalin-ether concentration techniques from August 1983 to December 1985. Out of them, 73.6% were free from any parasite, 22.6% were ova positive and 4.0% cyst positive. The ova positive rates by species were Ascaris lumbricoides 2.0%, Trichuris trichiura 13.0%, hookworm and Trichostrongylus orientalis 0.08% respectively, Clonorchis sinensis 7.6%, Metagonimus yokogawai 1.1%, Paragonimus westermani 0.08%, Echinostoma hortense 0.04%, Fibricola seoulensis 0.9%, Taenia sp. 0.3%, Hymenolepis nana 0.2% and H. diminuta 0.04%. Most of them (87.3%) were positive by a species, 11.9% by two and 0.8% by 3 species. The cyst positive rates were Entamoeba histolytica 0.6%, E. coli 1.4%, Endolimax nana 1.7%, Iodoameba butschlii 0.04% and Giardia lambla 0.9%. Among the cyst positives, 89.5% were positive by a species, 7.6% by two and 0.5% by 3 species. The intestinal parasite infections among the Korean soldiers decreased distinctly compared with previous data.
parasitology-helminth-nematoda ; trematoda ; cestoda ; protozoa ; epidemiology ; Clonorchis sinensis ; Trichuris trichiura ; Metagonimus yokogawai ; hookworm ; Ascaris lumbricoides ; Diphyllobothrium latum ; Hymenolepis nana ; Entamoeba histolytica ; Giardia lamblia ; Entamoeba coli ; Endolimax nana ; Trichostrongylus orientalis ; Paragonimus westermani ; Echinostoma hortense ; Fibricola seoulensis ; Taenia sp. ; Hymenolepis diminuta

This study was conducted to evaluate prevalence of intestinal helminthic infections and skin tests and Paragonimus and Clonorchis in tuberculosis(TB) patients in Korea. Stool examinations by formalin-ether technique and intradermal tests were carried out in 2 areas; Masan TB hospital and Kong-Ju TB hospital. The positive rate of intestinal helminths of any kind was 51.7 percent among 329 patients in Masan hospital, but 18.1 percent among 215 patients in Kong-Ju hospital. The infection rates of Trichocephalus trichiurus and Clonorchis sinensis were 20.7 percent and 17.6 percent respectively in Masan hospital patients, but the infection rates of T. trichiurus and C. sinensis were 6.5 percent and 6.0 percent respectively in Kong-Ju hospital patients. In skin tests, positive reactions to Paragonimus and Clonorchis antigens were 22.0 percent and 37.6 percent respectively in Masan hospital patients. On the contrary, Kong-Ju hospital patients showed the positive rates of 15.2 percent for Paragonimus and 27.2 percent for Clonorchis respectively.
parasitology-helminth-trematoda ; Ascaris lumbricoides ; Trichuris trichiura ; hookworm ; Trichostrongylus orientalis ; Clonorchis sinensis ; Paragonimus westermani ; Metagonimus yokogawai ; Taenis sp. ; Hymneolepis nana ; epidemiology ; skin test

An epidemiological study on Metagonimus yokogawai infection was performed in Samcheok-gun, Kangwon province during the period from November 1983 to October 1984. Formalin-ether concentration technique and Stoll's dilution egg counting method were employed to figure out the prevalence and infection intensity of M. yokogawai infection. The results are summarized as follows: The prevalence of M. yokogawai infection was 13.3 percent among 1,172 examined ; 18.0 percent (114 out of 632) in male and 7.8 percent (42 out of 540) in female. The prevalence rates were different by stream; 15.5 percent in Ohsip-chon (stream), 11.8 percent in Maeup-chon and 1.6 percent in Gagok-chon. Along the basin of Oship-chon; 8.2 percent at the lower reaches in Samcheok-eup, 25.9 percent at the middle reaches in Miro-myon and 6.2 percent at the upper reaches in Dogeoe-eup, respectively. By age group, the highest rate (18.3-20.2 percent) was observed in 30-49 years of age (male : 24.1-28.7 percent, female 11.2-13.2 percent). By social strata, the positive rate was 15.0 percent (120 out of 799) in general inhabitants and 9.7 percent (36 out of 373) in school children. Intensity by EPG count in feces was 419 in average; the light infection (less than 400 EPG) was 70.4 percent, moderate infection (401-1,000 EPG) 19.4 percent and heavy infection (more than 1,001 EPG) 10.2 percent respectively. All the 67 sweetfish (length 10.3-18.5 cm) which were caught from Ohsip-stream were infected with metacercariae of M. yokogawai and the number of metacercariae detected were 382 per fish in average (323 in June and 382 in September). Experiences of intake of raw fresh-water fish [Plecoglossus altivelis and Leuciscus (Tribolodon) sp.] were present in 50.3 percent (354 out of 704) of the inhabitants along Ohsip-stream according to questionnaire study. The results of this survey indicated that the middle reaches of Ohsip-stream in Miro-myon, Samcheok-gun is the endemic region for M. yokogawai infection.
parasitology-helminth-trematoda ; Metagonimus yokogawai ; epidemiology ; metagonimiasis ; human ; Plecoglossus altivelis ; Leuciscus sp.

Helminthic zoonoses are of significant importance to the public health and to the socioeconomic consequences especially in lost-meat, animal products and animal labor. For past several decades in Korea, it has been recognized that endoparasitic infections among domestic animals are extremely common and many of the helminth parasites of man have been acquired from, or are shared with domestic animals. However, there was no survey of a nationwide scale on the prevalence of animal helminthiasis; and control measures are also not satisfactory. Furthermore, because of the remarkable increase in the demand, number of domestic animals and pets is rapidly increasing in these days. Therefore, an extensive study on zoonotic helminths was carried out from July 1980 throughout August 1981 to understand the present status and parasite-host relationship from the epidemiological viewpoont. A total of 13,685 fecal specimens of cattles, sheeps, pigs, dogs and cats was collected from 26 localities in the country. The specimens were examined by formalin-ether centrifugal sedimentation technique. The results are summarized as follows: Of 13,685 specimens examined, 9,808(71.7 percent) were positive for helminth parasites. The positive rates were 99.0 percent in cattles, 86.5 percent on sheeps, 85.4 percent in pigs, 35.4 percent in dogs, 15.1 percent in cats. Single infection showed the highest rate (60.0 percent), and double infection(27.5 percent), triple(8.1 percent), quadruple(2.8 percent), quintuple(1.5 percent) and hexad(0.1 percent) were in decreasing order. In the present study, 18 species zoonotic helminths were found: 11 nematodes, 6 trematodes and 1 cestode. According to province, Cheju revealed the highest rate 84.8 percent, then Kyungnam 77.5 percent, Jeonnam 75.6 percent, Jeonpuk 75.4 percent, Kyonggi 75.2 percent, Chungnam 71.7 percent, Chungpuk 70.6 percent and Kangwon 64.2 percent were in decreasing order and Busan and Seoul showed 70.4 percent and 58.1 percent, respectively. Rural area showed slightly higher rate (74.7 percent) than urban area (68.5 percent), and rates of mountainous area (70.4 percent) and plain area (71.1 percent) are very similar. According to animal, helminths species and positive rates appeared in: Cattles: 6 nematodes and 3 trematodes; Strongyles 26.4 percent, Neoascaris vitulorum 24.1 percent, Trichuris ovis 12.0 percent, Nematodirus sp. 6.3 percent, Srongyloides papillosus 5.1 percent, Capillaria bovis 0.02 percent, Paramphistomum sp. 41.5 percent, Fasciola hepatica 33.2 percent and Eurytrema pancreaticum 29.7 percent. Sheeps: 3 nematodes and 2 trematodes: Strongyles 33.0 percent, S. papillosus 26.9 percent, Nematodirus sp. 14.6 percent, F. hepatica 31.7 percent and E. pancreaticum 19.6 percent. Pigs: 5 nematodes and 2 trematodes: Strongyles 43.1 percent, Ascaris suum 29.0 percent, Metastrongylus apri 20.3 percent, Trichuris suis 14.0 percent, Strongyloides ransomi 12.1 percent, Clonorchis sinensis 1.4 percent and Paragonimus westermani 0.9 percent, Dogs: 4 nematodes and 3 trematodes and 1 cestode: Toxocara canis 14.4 percent, Trichuris vulpis 9.5 percent, Ancylostoma caninum 8.0 percent, Toxascaris leonina 4.0 percent, C. sinensis 2.4 percent, Metagonimus yokogawai 1.3 percent, P. westermani 0.8 percent and Spirometra sp. 0.9 percent, Cats: 2 nematodes, and 3 trematodes and 1 cestode: Toxocara cati 7.7 percent, Ancylostoma tubaeforme 3.1 percent, C. sinensis 1.9 percent, P. westermani 1.4 percent, M. yokogawai 1.2 percent and Spirometra sp. 0.7 percent.
parasitology-helminth-nematoda-trematoda-cestoda ; cattle ; sheep ; pig ; dog ; cat ; epidemiology ; zoonosis ; Fasciola hepatica ; Eurytrema pancreaticum ; Paramphsitomum sp. ; Neoascaris vitulorum ; Trichuris ovis ; Strongyloides papillosus ; Nematodirus sp. ; Capillaria bovis ; Clonorchis sinensis ; Paragonimus westermani ; Ascaris suum ; Trichuris suis ; Strongyloides ransomi ; Metastrongylus apri ; Spirometra sp. ; Metagonimus yokogawai ; Toxocara canis ; Toxocara leonina ; Ancylostoma caninum ; Trichuris vulpis ; Ancylostoma tubaeforme ; Strongyles

This study was undertaken to elucidate the status of Metagonimus species infection and to demonstrate the first and the second intermediate hosts of the fluke at the several localities along the Gum river, Chungchung-nam Do, Korea from March 1979 to October 1980. The results are summarized as follows: Total 790 stool specimens of inhabitants from 6 localities along Gum river were examined by the combination of cellophane thick smear technique and formalin-ether concentration technique. The positive rate of intestinal helminths was 80.3 percent, and the egg positive rate of Metagonimus sp. was 21 percent from a total of 790 specimens examined. In the age bracket of 20-49, the positive rates of Metagonimus sp. were 31.1-36.5 percent, and the males (26.8 percent) were infected three times higher than females (8.9 percent). By the area of the river, Gumsan which is located upper stream showed the highest positive rate (40.5 percent) of the fluke, whereas the rates decreased gradually toward upper part of river (Muju) or the descending lower area of the river. The most lower area of river (Gangkyeong and Nonsan), no positive Metagonimus infection case was found. The infection rate of Clonorchis sinensis in 790 was 37.3 percent, and the status of mixed infection of Metagonimus with C. sinensis was found 127 cases (76 percent) out of 166 cases with Metagonimus infection. The result of measurement of ova from 166 cases of Metagonimus infection, large ova were found in 41.1 percent, small size ova in 31.9 percent and the mixed type in 27.1 percent, respectively. The adult worms were recovered from the 6 cases after treatment with niclosamide, and the measurements of the worms showed similar morphological characteristics of the Metagonimus yokogawai. Twenty-two species in 5 families of fresh water fish were caught. Out of 22 species of fish, 18 species were found infected with metacercaria of Metagonimus. In order to observe the distribution of metacercariae in the body and the rate of infection of the individual host, a total of 94 Pseudogobio esocinus were examined. Total 84 (89.4 percent) out of 94 fish were infected with the metacercariae and the rates of distribution of the metacercaria were observed in the following order: on scale; 93.4 percent, in gill; 3.2 percent, head part; 2.9 percent, but a few metacercaria was found in muscle and visceral organs. The development of the metacercariae which were isolated from the scale of Pseudogobio esocinus were experimentally traced in the albino rat host from one day to 30 days after infection. At the 6th day, several eggs were visible in the uterine tubule of the some worms, on the 10th day, worms became 326.0 x 208.0 micrometer in size, however the bodies of worms grew no more until the 30th day after infection. The oral sucker was larger in size than the ventral sucker during early stage of the worms, but the 7th day after infection, it reversed. The ventral sucker situated on the ventral right side of the body. Right side of testis laid somewhat toward, and uterus and vetellaria extended to the posterior margin of the right testis. Snails(Koreanomelania nodifila var. ovulum) were collected in the river, Buri-Myeon, Gumsan-Gun, and found the natural emerging ophthalmo-pleurophocercus cercaria. From the above result, the prevalence of Metagonimus species infection showed relatively higher rates from the inhabitants along the middle to upper localities of the river. Even though no sweetfish was caught in the surveyed areas, Gum river basin is the one of the new endemic foci of metagonimiasis in Korea.
parasitology-helminth-trematoda ; Metagonimus spp. ; metagonimiasis-epidemiology ; taxonomy ; Ascaris lumbricoides ; Trichuris trichiura ; hookworm ; Trichostrongylus orientalis ; Clonorchis sinensis ; Taenia sp. ; Pseudogobio esocinus ; Acheilognathus intermedia ; Carassius carassius ; Hemibarbus labeo ; Hemibarbus longirostris ; Paracheilognathus rhombea ; Parapelecus jouyi ; Pseudopungtungia nigra ; Pungtungia herzi ; Sarcocheilichthys wakiyae ; Zacco playtpus ; Zacco temmincki ; Gobiobotia brevibarba ; Gobiobotia macrocephalus ; Siniperca kawamebari ; Siniperca scherzeri ; Liobagrus andersonii ; Pelteobargrus fluvidraco ; Pseudobagrus emarginatus ; Pseudobagrus sp. ; Mogurnda obscura ; Parasilurus asotus

A survey of intestinal parasites was performed during the period from April 1970 to December 1971 in ROKA (Republic of Korea Army) soldiers. Samples were collected from 591 Army troops(enlisted men), 1,755 recruits at completion of 6 weeks basic training, 304 recruits during basic training and 245 stool specimens of students of ROKA Nursing School at Taegu area. Each of the specimens was examined one time or twice under the microscope, one for protozoan cysts stained with iodine solution and the other for helminth eggs. Findings were summerized as follows: A positive rate of intestinal parasites was 88.0 percent by Formalin-Ether concentration method and 89.2 percent by Kato's method. Of the 541 soldiers examined by Formalin-Ether concentration method, the infection rate of A. lumbricoides was 28.1 percent, T. trichiurus 79.3 percent, hookworm 14.2 percent, T. orientalis 30.7 percent, C. sinensis 7.8 percent and M. yokogawai 0.6 percent. Of the 1,532 soldiers examined by Kato's method A. lumbricoides showed positive rate of 45.8 percent, T. trichiurus 78.3 percent, T. orientalis 1 4.5 percent, hookworm 7.5 percent, C. sinensis 6.6 percent and Taenia sp. 0.6 percent. The incidence of E. vermicularis out of 822 samples was 19.8 percent from the anal swabs. E. histolytica was recovered in 4.2 percent among 541 samples, E. coli 6.1 percent and also infected G. lamblia, E. nana, I. butschlii and Chilomastix mesnili. Most of the infected cases revealed single or double infections.
parasitoloyg-helminth-nematoda-trematoda-cestoda-protozoa ; Ascaris lumbricoides ; Trichocephalus trichiurus ; hookworm ; Trichostrongylus orientalis ; Clonorchis sinensis ; Metagonimus yokogawai ; Taenia sp. ; Enterobius vermicularis ; Entamoeba coli ; Entamoeba histolytica ; Giardia lamblia ; Endolimax nana ; Iodamoeba butschlii ; Chilomastix mesnili ; epidemiology

The authors examined 3,169 fecal specimens from inhabitants of seven localities such as City, Eups and Myons in Cheju Do on July 1970 with cellophane thick smear technique. The results were analysed and summarized as follows: The overall egg positive rate of helminths was 82.2% and it was attributed to high rates of soil-transmitted helminths as in case of other parts in Korea. The infection rates of each species were; A. lumbricoides 44.3%, T. trichiurus 65.6%, hookworm 1.5%, T. orientalis 0.8%, C. sinensis 0.2%, P. westermani 0.4%, M. yokogawai 0.9%, Taenia sp. 12.7% and H. nana 1.4%. The infection rates of soil-transmitted helminths were relatively lower than those of mainland Korea especially in case of hookworm and T. orientalis. The proportion of unfertilized ova passers among the Ascaris infected case was 22.1%. The ova of heterophyids, most probably Metagonimus yokogawai were detected in lower percentage but discovered throughout the localities surveyed and in all age groups. It is certainly presumed that Metagonimus infection is autochthonous. The most interesting results were obtained in Taenia sp. infection and the higher rates were shown in rural area than in urbanized areas. The positive rates were within 5% in childhood and adolescence but abruptly increased up to 36.4 % in adults.
parasitology-helminth-nematoda-trematoda-cestoda ; Ascaris lumbricoides ; Trichuris trichiura ; hookworm ; Trichostrongylus orientalis ; Clonorchis sinensis ; Paragonimus westermani ; Metagonimus yokogawai ; Taenia sp. ; Hymenolepis nana