1.Egg Laying Capacity of Haplorchis taichui (Digenea: Heterophyidae) in Humans.
Megumi SATO ; Surapol SANGUANKIAT ; Somchit PUBAMPEN ; Teera KUSOLSUK ; Wanna MAIPANICH ; Jitra WAIKAGUL
The Korean Journal of Parasitology 2009;47(3):315-318
Quantitative fecal egg counts represented as the number of eggs per gram of feces (EPG) are generally a reliable parameter to estimate the worm burden of intestinal and hepatic parasitoses. Although Haplorchis taichui (Digenea: Heterophyidae) is one of the most common minute human intestinal flukes, little is known about the relationship between EPG and the actual worm burden in patients or the severity of the disease. In the present study, fecal samples were collected from 25 villagers in northern Thailand before and after praziquantel treatment. The EPG values of each participant were determined by the modified cellophane thick smear method, and adult worms were collected from the whole stool after the treatment. Eggs per day per worm (EPDPW) of H. taichui were estimated 82 from egg counts and expelled worms. The EPG was not well correlated with the worm burden, and a reverse correlation was observed between the EPDPW and the worm burden.
Animals
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Feces/parasitology
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Heterophyidae/isolation & purification/*physiology
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Humans
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Parasite Egg Count
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Trematode Infections/*parasitology
2.A review of Gymnophalloides seoi (Digenea: Gymnophallidae) and human infections in the Republic of Korea.
Soon Hyung LEE ; Jong Yil CHAI
The Korean Journal of Parasitology 2001;39(2):85-118
Studies on Gymnophalloides seoi (Digenea: Gymnophallidae) and human infections are briefly reviewed. This minute intestinal fluke was first discovered from a Korean woman suffering from acute pancreatitis and gastrointestinal troubles. It was described as a new species by Lee, Chai and Hong in 1993. The southwestern coastal village where the patient resided was found to be a highly endemic area, and additional endemic areas have been identified. The parasite is very small, 0.33-0.50 mm long and 0.23-0.33 mm wide, and characterized by the presence of a ventral pit. The first intermediate host remains unknown, but the second intermediate host has been found to be the oyster Crassostrea gigas. Man and the Palearctic oystercatcher Haematopus ostralegus have been shown to be natural definitive hosts, and wading birds including the Kentish plover Charadrius alexandrinus are highly susceptible to experimental infection. Gerbils, hamsters, cats, and several strains of mice were also susceptible laboratory hosts. In experimentally infected mice, the parasites inhabit the small intestine, pinching and sucking the root of villi with their large oral suckers, but they did not invade beyond the mucosa in immunocompetent mice. However, they were found to invade the submucosa in immunosuppressed mice. Human G. seoi infections have been found in at least 25 localities; 23 islands on the Yellow Sea or the South Sea, and 2 western coastal villages. The highest prevalence was found in a village on Aphaedo, Shinan-gun (49% egg positive rate); other areas showed 0.8-25.3% prevalence. Infected people complained of variable degrees of gastrointestinal troubles and indigestion. The infection can be diagnosed by recovery of eggs in the feces; however, an expert is needed to identify the eggs. Praziquantel, 10 mg/kg in single dose, is effective for treatment of human infections. Eating raw oysters in endemic areas should be avoided.
Animals
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Feces/parasitology
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Host-Parasite Relations
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Human
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Immunocompromised Host
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Intestine, Small/parasitology
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Korea/epidemiology
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Life Cycle Stages
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Parasite Egg Count
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Prevalence
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*Trematoda/classification/ultrastructure
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*Trematode Infections/epidemiology/parasitology
3.Egg positive rate of Enterobius vermicularis among preschool children in Cheongju, Chungcheongbuk-do, Korea.
Seokha KANG ; Hyeong Kyu JEON ; Keeseon S EOM ; Joong Ki PARK
The Korean Journal of Parasitology 2006;44(3):247-249
In an attempt to determine the prevalence of pinworm infection, the egg positive rate of Enterobius vermicularis was examined using the adhesive cello-tape anal swab method in 1,512 preschool children sampled from a total of 20 kindergartens in Cheongju city, in November to December of 2004 (951 children from 13 kindergartens) and September to October of 2005 (561 from 7 kindergartens). The overall egg positive rate was found to be 7.9% (119/1,512); 9.3% (73/784) for boys and 6.3% (46/728) for girls, respectively. The 5-year age group evidenced the highest egg positive rate (10.9%, 47/430) among the examined age groups. As compared to those reported from previous works (ranged from 9.2 to 26.1%), the prevalence of E. vermicularis in the Cheongju city area is relatively low.
Parasite Egg Count
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Male
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Korea/epidemiology
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Humans
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Female
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Enterobius/*growth & development
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Enterobiasis/*epidemiology/parasitology
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Child, Preschool
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Child
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Animals
4.Egg positive rate of Enterobius vermicularis of primary school children in Geoje island.
Bong Jin KIM ; Bo Young LEE ; Hyun Kee CHUNG ; Young Sun LEE ; Kun Hee LEE ; Hae Jin CHUNG ; Mee Sun OCK
The Korean Journal of Parasitology 2003;41(1):75-77
The status of pinworm (Enterobius vermicularis) egg positive rate of primary school children in Geoje island was investigated by using adhesive cellotape anal swap method, in September, 2002. Total egg positive rates of E. vermicularis were 9.8% (74/754) and those of male and female were 10.8% and 8.7%, respectively. Among three schools examined, Myeongsa primary school showed the highest egg positive rate (12.6%) followed by Yeoncho [9.8% (26/266)] and Geoje [9.1% (35/385)]. As for the age groups, the 2nd grade had the highest egg positive rate (15.3%), whereas the 5th grade showed the lowest egg positive rate (2.6%). The above result led us to confirm that the egg positive rates of E. vermicularis in primary school children in Geoje island were not significantly different from the those in the whole country including urban and rural areas, showing more than 10%.
Animals
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Child
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Enterobiasis/*epidemiology
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Enterobius/*isolation & purification
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Feces/parasitology
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Female
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Geography
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Humans
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Korea
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Male
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*Parasite Egg Count
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Students
5.Persistent infection with Strongyloides venezuelensis in the Mongolian gerbil (Meriones unguiculatus).
Byeong Kirl BAEK ; In Soo WHANG ; M Khyrul ISLAM ; Byeong Soo KIM ; Ibulaimu KAKOMA
The Korean Journal of Parasitology 2002;40(4):181-186
To examine the fate of Strongyloides venezuelensis. Mongolian gerbils (Meriones unguicalatus) were orally infected with 1,000 L3 larvae per animal. Altogether, 50 gerbils divided into 5 groups of 10 each were monitored for a period of 570 days to document the kinetics of faecal egg output, adults worm population, morphological development, fecundity, and hematological changes including peripheral blood eosinophilia. This study chronicled a life long parasitism of S. venezuelensis in the gerbil host, and showed that S. venezuelensis infection was quite stable throughout the course of infection and the worms maintained their normal development as evidenced by their body dimension. A progressive loss of body condition of the infected gerbils was observed as the level of infection advanced. However, no detectable pathological changes were observed in the gastrointestinal tract. The present findings indicate that an immunocompetent host, such as the Mongolian gerbil, can serve as a life long carrier model of S. venezuelensis if the worms are not expelled within 570 days after infection.
Animals
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Blood Cell Count
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Disease Models, Animal
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Feces/parasitology
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Gerbillinae/*parasitology
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Parasite Egg Count
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Strongyloides/*growth & development/pathogenicity
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Strongyloidiasis/blood/*parasitology
6.Animal Models for Echinostoma malayanum Infection: Worm Recovery and Some Pathology.
Jiraporn SONGSRI ; Ratchadawan AUKKANIMART ; Thidarut BOONMARS ; Panaratana RATANASUWAN ; Porntip LAUMMAUNWAI ; Pranee SRIRAJ ; Panupan SRIPAN
The Korean Journal of Parasitology 2016;54(1):47-53
Echinostomes are intestinal trematodes that infect a wide range of vertebrate hosts, including humans, in their adult stage and also parasitize numerous invertebrate and cold-blooded vertebrate hosts in their larval stages. The purpose of this study was to compare Echinostoma malayanum parasite growth, including worm recovery, body size of adult worms, eggs per worm, eggs per gram of feces, and pathological changes in the small intestine of experimental animals. In this study, 6-8-week-old male hamsters, rats, mice, and gerbils were infected with echinostome metacercariae and then sacrificed at day 60 post-infection. The small intestine and feces of each infected animal were collected and then processed for analysis. The results showed that worm recovery, eggs per worm, and eggs per gram of feces from all infected hamsters were higher compared with infected rats and mice. However, in infected gerbils, no parasites were observed in the small intestine, and there were no parasite eggs in the feces. The volume of eggs per gram of feces and eggs per worm were related to parasite size. The results of histopathological changes in the small intestine of infected groups showed abnormal villi and goblet cells, as evidenced by short villi and an increase in the number and size of goblet cells compared with the normal control group.
Animals
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Body Size
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*Disease Models, Animal
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Echinostoma/growth & development/isolation & purification/*physiology
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Echinostomiasis/*parasitology/*pathology
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Feces/parasitology
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Intestine, Small/parasitology/pathology
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Parasite Egg Count
7.An epidemiological survey on Cryptosporidium parvum infection of inhabitants in Chorwon-gun, Kangwon-do.
Min SEO ; Sun HUH ; Jong Yil CHAI ; Jae Ran YU
The Korean Journal of Parasitology 2001;39(2):201-203
The present study was undertaken to know the infection status of Cryptosporidium parvum among the residents of Chorwon-gun, Kangwon-do in 1993. Total 461 fecal samples were collected from the inhabitants residing in Chorwon-gun during the period of August 12 to September 14, 1993. Fecal smears were prepared by formalin-ether sedimentation, and examined after modified acid fast staining. Of the 461 fecal samples, 9 (1.9%) were positive for C. parvum oocysts. The positive cases were limited to thirties (4) patients, forties (3), and sixties (2), and no oocyst was detected in other age groups. The oocyst positive rate for male was 1.4% and that of female was 2.6%.
Adolescent
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Adult
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Age Factors
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Aged
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Animals
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Child
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Cryptosporidiosis/*epidemiology/parasitology
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Cryptosporidium parvum/isolation & purification
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Feces/parasitology
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Female
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Human
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Korea/epidemiology
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Male
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Middle Aged
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Parasite Egg Count
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Sex Factors
8.Comparison of Egg Positive Rates of Enterobius vermicularis among Preschool Children in Three Korean Localities.
Sung Hee HONG ; Sang Eun LEE ; Young Il JEONG ; Won Ja LEE ; Shin Hyeong CHO
The Korean Journal of Parasitology 2011;49(4):441-443
This survey was performed to investigate and compare egg positive rates (EPRs) of Enterobius vermicularis among preschool children in 3 Korean localities (Chuncheon-si, Inje-gun, and Paju-si) in 2008. A total of 7,048 preschool children were examined. Overall, the total EPR was 4.0%; the EPR was the highest in Chuncheon-si (5.6%), followed by Inje-gun (4.5%) and Paju-si (3.4%). The EPR of boys (4.9%) was higher than that of girls (3.1%). The EPR significantly increased with age, with the highest observed in 5~7-year-olds. These findings demonstrate that E. vermicularis infection is widely prevalent among preschool children in Chuncheon-si, Inje-gun, and Paju-si, Republic of Korea.
Animals
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Child
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Child, Preschool
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Enterobiasis/*epidemiology/parasitology
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Enterobius/*isolation & purification
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Female
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Humans
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Infant
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Male
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*Parasite Egg Count
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Prevalence
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Republic of Korea/epidemiology
9.Infection status of pigs with Cryptosporidium parvum.
The Korean Journal of Parasitology 2004;42(1):45-47
To investigate the infection status of pigs with Cryptosporidium parvum, 589 fecal samples were collected from pigs raised at farm in Chungcheongbuk-do and Chungcheongnam-do. Of the 589 pig fecal samples, 62 (10.5%) were positive for C. parvum. The area showing the highest positive rate was Dangjin-gun, Chungcheongnam-do (14.0%), and the lowest (0%) Salmi-myon, Chungcheongbuk-do. The positive rate of C. parvum in Judok-eup increased from 12.7% in the winter to 22.1% in the summer. The results of this study suggest that the pigs may be a source of human C. parvum infection.
Animal Husbandry
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Animals
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Cryptosporidiosis/epidemiology/parasitology/*veterinary
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Cryptosporidium parvum/*isolation & purification
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Feces/parasitology
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Korea/epidemiology
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Parasite Egg Count
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Swine
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Swine Diseases/*epidemiology/*parasitology
10.Correlation of egg counts of Clonorchis sinensis by three methods of fecal examination.
Min Ho CHOI ; Tao GE ; Shang YUAN ; Sung Tae HONG
The Korean Journal of Parasitology 2005;43(3):115-117
The Kato-Katz (KK) method is a well-known method of fecal examination for helminthiases. Its diagnostic sensitivity was found very high for clonorchiasis. The present study evaluated the correlation of Clonorchis sinensis egg counts by the KK method with those by direct smear and formalin-ether (FE) technique. The egg counts obtained by the KK method (Y) were correlated with the counts by direct smear (X) with the equation of Y = 659.4 + 0.266X (r2= 0.738), but not with those by the FE method. The present study demonstrated that the KK method and direct smear were useful for both qualitative and quantitative diagnosis of clonorchiasis, especially in the field.
Animals
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Cellophane
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Clonorchiasis/*diagnosis/parasitology
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Clonorchis sinensis/*isolation & purification
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Comparative Study
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Ether, Ethyl
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Feces/parasitology
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Formaldehyde
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Humans
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Parasite Egg Count/*methods
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Sensitivity and Specificity