• Parasites, Hosts and Diseases
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• v.32 no.1
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• pp.27-34
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• 1994

The results of fecal examination for helminth eggs and protozoan cysts in Seoul Paik Hospital during 1984-1992 are reported. Fecal specimens of a total of 52,552 out- or in- patients were examined by formalin-ether sedimentation and/or direct smear method. The overall egg Positive rate of helminths was 6.5% and the cyst Positive rate of Protozoa 2.5%. The egg positive rate (number of positive cases) for each species of helminth was; Clonorchis sirensis 3.2%(1,667) , Trichuris trichiura 2.0%(1,089), Metqsonimw yokogawai 1.2% (613), Ascaris lumbricoides 0.2% (100), Trichostrongylus orientalis 0.1% (34), Taenin spp. 0.05% (28), Hymenolepis nana 0.03% (181), hookworms 0.03% (17), Poragonimlrkf westermani 0.02% (12), Echinostoma spp. 0.03% (12), Enterobius uermiculans 0.02% (10), Strongyloides stercora;is (larvae) 0.01% (6) , and Diphyllobothrium latum 0.004% (2). The cyst positive rate (number of positive casesl for each protozoan was; Entamoebc coli 1.1% f5881, Snnolimox nana 0.8% (402), Ginrdin lomblia 0.3% (173) , Entamoeba histo;utoca 0.3% (164), and Trichomonos hominis (trophozoites) 0.004% (2). Viewing from the data of 9 years, it was evident that the prevalence of soil-transmitted helminths such as A. Lumbricoines and T. trichiuro has been decreasing remarkably, while that of snail transmitted helminths such as C. sinenris and intestinal protozoans has not.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.109-115
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• 1984

In order to estimate the recent patterns of intestinal helminth infections among the residents in Taegu City, Korea, a survey based on discovery of helminth eggs by formalin-ether sedimentation and modified Graham's scotchtape anal swab techniques, were performed during the period from March to September in 1983. A total of 1, 697 fecal specimens were collected from 854 male and 843 female residents from 5 village (Dong), each of whom were selected randomly to represent 1, 000 persons referred to the census in 1982. Among the specimens examined, one or more species of helminth parasites were found in 473, revealing the overall positive rate of 27.9 per cent. Of them, Trichuris trichiura was found most frequently, in 13.2 percent, followed by Enterobius vermicularis in 7.0 per cen t. Hookworm was the least prevalent. The sex-specific rate of overall helminth infections was a little higher in females than in males, while in cases of Clonorchis sinensis, Metagonimus yokogawai and Taenia species, the infection rates in males was higher than in females. T. trichiura was most prevalent in the 20~29 age group and showed about the same prevalence in males and females of all age groups. C. sinensis infection rate increased with age while those of Ascaris lumbricoides decreased. Single infections were 82.5 per cent of all positive cases. Of these, T. trichiura revealed the highest prevalence in 31.7 per cent, followed by E. vermiculasis in 20.1 per cent and A. lumbricoides in 14.8 per cent. Of the double infections, the percentage of T. trichiura in combination with other intestinal helminths was higher than that of A. lumbricoides. It was concluded that although the infection rates of intestinal helminths among the residents in Taegu City, Korea is still high, eradication of these parasitic diseases seems to be possible with twice-a-year administration of specific anthelmintics, in combination with extensive public health education and improvement of the dietary life.

• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.213-218
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• 2007

The prevalence of liver and intestinal fluke infections was surveyed on residents of Savannakhet Province, Laos. Fecal specimens were collected from a total of 981 residents in 4 Mekong riverside villages and examined by the Kato-Katz thick smear technique. The results revealed that the overall helminth egg positive rate was 84.2%, and the positive rate for small trematode eggs, including Opisthorchis viverrini, heterophyids, or lecithodendriids, was 67.1 %. To obtain adult flukes, 38 small trematode egg positive cases were treated with a 20-30 mg/kg single dose of praziquantel and purged. Diarrheic stools were then collected from 29 people and searched for helminth parasites using stereomicroscopes. Mixed infections with O. viverrini and 6 kinds of intestinal flukes were found, namely, Haplorchis taichui, Haplorchis pumilio, Haplorchis yokogawai, Prosthodendrium molenkampi, Phaneropsolus bonnei, and echinostomes. The total number of flukes collected was 7,693 specimens (av. no. per treated person; 265.3). The most common species was O. viverrini, followed by H. taichui, P. molenkampi, echinostomes, H. pumilio, P. bonnei, and H. yokogawai. The results indicate that foodborne liver and intestinal fluke infections are prevalent among residents of Savannakhet Province, Laos.

• Parasites, Hosts and Diseases
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• v.47 no.1
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• pp.37-47
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• 2009

National surveys on the prevalence of intestinal parasitic infections have been carried out every 5-7 years since 1971 in the Republic of Korea in order to establish control measures. The present nationwide survey was conducted from June to December 2004. The 10% population sampling data of Population and Housing Census by the Korean government in 2000 was used as the survey population. One sample was selected randomly from each of the 22,858 registered subjects, and a total of 20,541 people were ultimately included in this survey. Fecal examinations were performed by the cellophane thick smear and saturated brine flotation techniques. Pinworm infection was examined by cello-tape anal swab method. This survey also included a questionnaire study for a socioeconomic analysis. The total helminth egg positive rate was 3.7%, and the estimated total positive number among nationwide people was 1,780,000. The rates in urban and rural areas were 3.1% and 6.8%, respectively. As the total egg positive rate in the 6th survey in 1997 was 2.4%, the present survey showed that there was a considerable degree of increase in the prevalence rate of intestinal parasitic infections over the 7-year period following the 6th survey. The largest increases occurred in the egg positive rates of Clonorchis sinensis and heterophyids including Metagonimus yokogawai.

• Parasites, Hosts and Diseases
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• v.60 no.4
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• pp.241-246
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• 2022

Felids are the unique definitive host of Toxoplasma gondii. The intestine of felid is the only site for initiating Toxoplasma gondii sexual reproduction. T. gondii excretes millions of infectious oocysts from the intestine, which are the primary source of infection. There are many difficulties in developing vaccines and drugs to control oocyst excretion due to the lack of an appropriate experimental model. Here, we established an in vitro feline intestinal epithelial cell (IEC) infection system and an efficient animal model of T. gondii Chinese 1 genotype, Wh6 strain (TgCtwh6). The Kunming mice brain tissues containing TgCtwh6 cysts were harvested 42-day post-infection. The bradyzoites were co-cultured with cat IECs in vitro at a ratio of 1:10. Five 3-month-old domestic cats were orally inoculated with 600 cysts each. The oocysts were detected by daily observation of cat feces by microscopy and polymerase chain reaction. We found that the parasite adhered and invaded cat IECs in vitro, transformed into tachyzoites, and then divided to form rose-like structures. These parasites eventually destroyed host cells, escaped, and finished the asexual reproduction process. Schizonts associated with sexual reproduction have not been observed during development in vitro cultured cells. However, schizonts were detected in all infected cat intestinal epithelial cells, and oocysts were presented in all cat feces. Our study provides a feasible cell model and an efficient infection system for the following studies of T. gondii sexual reproduction, and also lays a foundation to develop drugs and vaccines for blocking excretion and transmission of oocysts.

• Korean Journal of Veterinary Research
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• v.29 no.3
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• pp.325-331
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• 1989

Five hundred and forty-eight samples of pig heart muscle were collected from the abattoirs of many regions in Korea to reveal the frequency of Sarcocystis infections and to identify the species from June 1988 to April 1989. Heart muscle of the pigs was inspected for sarcocysts by the direct detection technique and for bradyzoites by the trypsin digestion technique. For examination of development of the parasites in the final host, 5 cross bred mature dogs, 5 puppies and 5 kittens were fed 100g, 50g and 50g of the infected meat respectively, four times in 2 days. Of 402 fattened and 146 older culled breeding pigs, 3 fattened pigs and 39 culled pigs were positive for Sarcocystis. Sarcocystis cysts from heart muscle measured an average of $425{\times}169{\mu}m$ and bradyzoites an average of $15.6{\times}3.5{\mu}m$. Of 15 animals, only 2 puppies were infected with Sarcocystis. The prepatent period was 11 to 12 days and patent period was not examined since the puppies were infected with some another infections and one died on day 11 and another died on day 12 after ingestion of the meat. The sporulated oocysts were detected 11 days after ingestion of the meat and sporocysts 12 days from the puppy feces. The sporulated oocysts measured an average of $16.5{\times}11.5{\mu}m$ and sporocysts an average of $12.6{\times}7.9{\mu}m$. On scraping examination of the intestinal mucosa, fully sporulated oocysts were detected in the tip of the intestinal villi. Considering above all descriptions, Sarcocystis in pig heart muscle in Korea was identified with Sarcocystis suicanis.

• Parasites, Hosts and Diseases
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• v.48 no.4
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• pp.339-342
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• 2010

Phongsaly Province, located in the northernmost area of Lao PDR, was previously suggested to be endemic for the liver fluke Opisthorchis viverrini infection. To confirm, or rule out, this suggestion, the Phonxay village in the Khoua District, Phongsaly Province, was selected for a survey. Ten volunteers (8 men and 2 women aged 31-57 years) who consumed raw freshwater fish and had gastrointestinal troubles were treated with a single dose of praziquantel (40 mg/kg) and pyrantel pamoate (10 mglkg) and purged with magnesium sulfate to recover any worm parasites. Eight of the 10 volunteers expelled 1 or more species of trematodes, nematodes, or cestodes (worm positive rate; 80%). The worms were morphologically identified as H. taichui (861 worms from 8 people), H. yokogawai (59 from 6 people), Phaneropsolus bonnei (1 from 1 person), Trichostrongylus sp. (2 from 2 people), Ascaris lumbricoides (2 from 1 person), Enterobius vermicularis (11 from 3 people), and Taenia saginata (1 strobila with scolex from 1 person). The results indicate that the mountainous area of Phongsaly Province, Lao PDR, is not endemic for the liver fluke but endemic for intestinal flukes, in particular, Haplorchis taichuiand H. yokogawai.

• CELLMED
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• v.9 no.4
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• pp.9.1-9.4
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• 2019

Ayurveda is one of the ancient systems of traditional medicine in India, however, there is a lack of proper scientific research and controlled studies on efficacy and toxicity of several Ayurvedic formulations using the methods of modern science, which hinders the proper development of Ayurveda, both in India and abroad. The present study was undertaken to further corroborate the efficacy of some popular anthelmintic Ayurvedic medicines, as evident by the pharmacological effects of Ayurvedic formulations on body surface of a cestode parasite. This study employed a common intestinal cestode of domestic fowl, Raillietina sp., as a model parasite, that was exposed in vitro to different concentrations of three common Indian Ayurvedic anthelmintic drugs, namely Krimimudgar Ras, Kriminol and Vidangasava, and also to a modern anthelmintic drug, praziquantel (PZQ). After the paralysis of parasites, the specimens from the highest drug-treated concentration (50 mg/ml), praziquantel (1 mg/ml), and control groups, were collected and processed for scanning electron microscopic studies to document the effects of drugs on the body surface of parasite. In this study, maximum degree of alterations on parasite body surface was observed in the worms exposed to Krimimudgar Ras, indicating this drug to be highly efficacious against intestinal worms and brings out a transtegumental mode of action on parasite. In conclusion, the findings of present study suggest that of the three Ayurvedic formulations tested, Krimimudgar Ras possesses significant anthelmintic effects, which are mediated through parasite's body surface. Therefore, Krimimudgar Ras may be considered as a reliable anthelmintic Ayurvedic formulation, as validated through this study.

• Parasites, Hosts and Diseases
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• v.60 no.3
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• pp.187-193
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• 2022

The positive rate of Clonorchis sinensis is the highest among intestinal parasites in the Republic of Korea (Korea). More than 1.2 million people were at risk of C. sinensis infection in Korea in 2012. An intensive control program is being implemented for residents of the 5 major river basins to reduce helminthic infections, including C. sinensis infection. This study evaluated the continuous intensive control program for parasitic diseases including clonorchiasis in areas near the 5 major river basins in Korea over the past 10 years (2011-2020). A total of 335,020 fecal samples (one sample per resident) prepared by the modified sedimentation technic were microscopically examined. Those who expelled helminth eggs were treated with anthelmintics through local health centers and re-examined 3 months later. The overall positive rate of helminths egg was 7.1%. The annual positive rates were dramatically decreased from 14.4% (2011) to 5.9% (2020). The egg positive rate was highest in C. sinensis (5.3%), followed by heterophyid flukes (1.5%) and Trichuris trichiura (0.2%). The prevalence of C. sinensis was significantly higher in males (7.6%) than in females (3.7%), and the highest in the 50-59 years (7.0%) age group. Our results are beneficial to establish prevention and control policies against helminthiases including clonorchiasis in endemic areas in this country.

• Korean Journal of Veterinary Research
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• v.29 no.2
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• pp.129-134
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• 1989

Fecal samples were taken from 402 cows in Posung, Chonnam where was designated as a place for Korean native cattle breeding. Prevalence of internal parasitisms were determined by the fecal examinations using the floatation and sedimentation procedures. 62.9% of the cows were found as positive cases with excretion of the eggs of Fasciola hepatica in the fecal specimens. Of those infected with F hepatica 97 cows free of other pathogenic intestinal parasites were chosen for albendazole treatment. Albendazole tablets(10mg/kg) were administered to the cows twice at the interval of 4 weeks. Blood samples were collected via jugular vein prior to the first treatment, four weeks after the first treatment and four weeks after the second treatment, respectively. At the same time fecal samples were collected for parasitological examinations by sedimentation methods. The mean pretreatment count was 44 fluke eggs per gram of feces, which compared with 27 epg and 17 epg four weeks after the first and second treatment, respectively. Most of the hematological and biochemical values fluctuated within the normal ranges during the experiment. Eosinophil counts were high initially, decreased after the first treatment and thereafter remained steady. The opposite was the case with aspartate and alanine aminotransferases.