Parvatrema chaii n. sp. (Digenea: Gymnophallidae) from mice experimentally infected with metacercariae collected from surf-clam, Mactra veneriformis

Parvatrema chaii n. sp. (Digenea: Gymnophallidae) is described using the worms recovered from experimentally infected mice in Korea. The metacercariae were collected from surf-clams, Mactra veneriformis, from a tidal flat in Sochon-gun, Chungchongnam-do. The metacercariae were elliptical (0.262 x 0.132 mm), and the genital pore had an anterior arch of 16-17 sensory papillae in scanning electron microscopic view. Adult worms were ovoid to foliate (0.275-0.303 by 0.140-0.150 mm), and their characteristic features included the presence of lateral lips, short esophagus, genital pore located some distance anterior to the ventral sucker, club-shaped seminal vesicle, a compact to slightly lobed vitellarium, elliptical eggs (0.018-0.020 by 0.010-0.013 mm), and absence of the ventral pit. This gymnophallid is classified as a member of the genus Parvatrema because of the location of the wide genital pore some distance from the ventral sucker, and the absence of the ventral pit. It differs from previously reported Parvatrema species, including the type species, P. borinquenae. In particular, the morphologies of the vitellarium and the genital pore with an anterior arch of 16-17 sensory papillae are unique features. Therefore, we propose it as a new species, Parvatrema chaii n. sp. (Digenea: Gymnophallidae).

Status of intestinal parasite infections among children in Bat Dambang, Cambodia

A survey was conducted to determine the extent of intestinal parasite infection in Bat Dambang, Cambodia in March 2004. A total of 623 fecal specimens was collected from kindergarten and schoolchildren and examined using the formalin-ether sedimentation technique. The overall infection rate of intestinal parasites was 25.7% (boys, 26.2%; girls, 25.1%), and the infection rates of intestinal helminthes by species were as follows: Echinostoma sp. 4.8%, hookworm 3.4%, Hymenolepis nana 1.3%, and Rhabditis sp. 1.3%. The infection rates of intestinal protozoa were; Entamoeba coli 4.8%, Giardia lamblia 2.9%, Iodamoeba butschlii 1.4%, Entamoeba polecki 1.1%, and Entamoeba histolytica 0.8%. There were no egg positive cases of Ascaris lumbricoides or Trichuris trichiura. All children infected were treated with albendazole, praziquantel, or metronidazole according to parasite species. The results showed that intestinal parasites are highly endemic in Bat Dambang, Cambodia.

Involvement of MAP Kinases in Apoptosis of Macrophage Treated with Trichomonas vaginalis

A primitive protozoan parasite Trichomonas vaginalis selectively activates the signal transduction pathways in macrophages (RAW264.7). This study evaluated the correlation of these signaling pathways and T. vaginalis-induced cell apoptosis. In macrophages infected with T. vaginalis, apoptosis was assessed on the basis of DNA fragmentation on agarose gel electrophoresis. Infection of macrophages with T. vaginalis induced tyrosine phosphorylation of several proteins. Infected cells with T. vaginalis were shown to associate with phosphorylation of the extracellular signal-regulated (ERK) 1/2 kinase, p38, c-Jun N-terminal kinase (JNK) mitogen-activated protein (MAP) kinases on Western blot analysis. The present finding also demonstrated a link between the ERK1/2, JNK and p38 apoptotic pathways that was modulated by T. vaginalis infection.

Susceptibility of several strains of mice to Echinostoma hortense infection

Susceptibilities of 5 different mice strains, including C3H/HeN, BALB/c, C57BL6, FvB and ICR, to Echinostoma hortense infection, was evaluated. The worm expulsion rate, worm size and egg production were observed from 1 to 8 weeks after infection with 30 metacercariae. C3H/HeN and ICR mice showed the highest worm maturation rates. The worm recovery rate and the number of eggs per gram (EPG) of feces was also higher in C3H/HeN and ICR mice than in BALB/c, C57BL6, and FvB mice. It is suggested that E. hortense is highly infectious to ICR and C3H/HeN mice, but not to the other strains of mice. Based on the results obtained, we believe that the susceptibility of different mouse strains to E. hortense infection is dependent on the genetic and immunologic background of mice.

Gordius Worm Found in a Three Year Old Girl's Vomitus

Since the Gordius worm is a parasite of crickets and several arthropods, cases of humans infected with this worm have been rare and accidental. A Gordius worm was obtained from a three-year-old girl who consulted a local clinic in Gwangju, Kyunggi-do, Korea. She lived in a rural area, and had eaten an insect that looked like a cricket. She expelled the worm in vomitus 15 minutes later; in fact, she expelled two worms, but one was discarded. The worm had a grayish white color and an intact outer surface. It was 16 cm in length and 0.6 cm wide. The posterior end of the worm was spirally enrolled and furcated into two caudal lobes, which were nearly cylindrical but showed a somewhat concave medio- ventral surface. The cloacal aperture was round and situated anterior to the point of bifurcation of the lobes. The cloacal aperture was encircled by a dark ring, which was a little removed from the aperture. The crescent fold was reddish brown, and no hairs were noticed over the entire body surface. The worm had the morphological features of a male Gordius. Accidental human cases involving the Gordius worm are rare and this is the first such case in Korea.

Status of intestinal parasites infection among primary school children in Kampongcham, Cambodia

A survey was made to find the extent of intestinal parasite infection in Kampongcham, Cambodia in February 2002. A total of 251 fecal specimens were collected from Tonlebat primary school children and examined by formalin-ether sedimentation technique. The overall infection rate of intestinal parasite was 54.2% (males, 57.3%; females, 50.8%). The infection rate of intestinal helminths by the species were as follows: Ascaris lumbricoides 26.3%, Echinostoma sp. 15.6%, hookworm 6.4%, Opisthorchis sp. 4.0%, Rhabditis sp. 2.4%, and Trichuris trichiura 0.4%. The infection rate of intestinal protozoa were as follows: E. coli 7.6%, G. lamblia 3.2%, I. butschlii 3.2%, and E. histolytica 0.8%. More than two different kinds of parasites were found in 16.7% of the stool samples. All the children infected were treated with albendazole, praziquantel and metronidazole according to parasite species. The results showed that intestinal parasites are highly endemic in this area.

A seroepidemiologic survey for human sparganosis in Gangweon-do

Gangweon-do is known to be highly endemic area of sparganosis more than other provinces in Korea. A seroepidmiologic examination for the detection of anti-Spirometra erinacei plerocercoid IgG in serum was carried out in normal inhabitants in Hongcheon-gun, Gangweon-do. Sere were tested by enzyme-linked immunosrobent assay (ELISA) for the anti-sparganum antibodies. Positive rate for anti-sparganum antibody in 719 adults was 3.3%. Data of the questionnaire for 24 ELISA positive inhabitants revealed that 20 had a history of eating raw meat of snakes, 24 had a history of eating frogs, and 24 had a history of drinking stream water. Two positive cases had a past history of sparganosis. Two positive cases showed current symptoms of sparganosis. The data revealed that ELISA would be useful to find infected cases among normal inhabitants at sparganosis-endemic areas.

Two rare cases of Diphyllobothrium latum parvum type infection in Korea

Two rare cases of human infection with parvum (dwarf) type of Diphyllobothrium latum [syn. D parvum (Stephens,1908)], were discovered in Korea. The first case was a 46-year old houseife, from whom a kind of pseudophyllidean tapeworm eggs was detected in the feces. She was treated with praziquantel and purged, and a complete strobila with scolex, 120 cm in total length, was recovered. She recalled that she had eaten raw trouts at a raw-fish restaurant near the Chungju Lake. Another patient was a 22-year old medical student (male), who used to eat raw sea-foods. He discovered a chain of tapeworm proglottids, 15 cm in length, discharged spontaneously in his stool and brought it for identification. The worms from the two cases were compatible with D. parvum (Stephens, 1908) of which the taxonomic significance has long been questioned. After a detailed morphological study and review of literature, we designated the worms as D. latum parvum type. This is the first report on the occurrence of this rare type of D. latum infection in Korea.

Epidemiological studies on Metagonimus infection along the Hongcheon river, Kangwon province

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.

Recent patterns of Enterobius vermicularis infection in some school children, Korea

To investigate the infection status of Enterobius vermicularis the author tried surveys by scotch-tape anal swap on school-children and household environmental factors considered to have influences on the infection were analyzed by an inquiry method with questionnaire. The survey was carried out in October 1986 and 1988 in urban and suburban areas and the results could summarized as follow: The egg positive rate in anal swab was 16.0 per cent (male 14.5 per cent, female 17.6 per cent) out of 2,156 school-children and higher in female group. The egg positive rate in suburban school-children (17.5 per cent out of 1,305 children of two primary school)was a little higher than that of urban school-children(13.6 per cent out of 851 children of one primary schools). The questionnaire analysis on environmental factors showed some significant relations between the egg positive rate and such factors as the number of brothers and sisters, householder's occupation, and avalibility of childroom or bathroom. The result indicate that, although enterobiasis in school-children has shown decreasing tendency in Korea, it is still considerably high in some urban and suburban areas.

Two cases of human infection by Echinostoma cinetorchis

Eggs of Echinostoma sp. were found from two patients who were hospitalized between Oct. and Dec. 1985. Single dose of 10 mg/kg of praziquantel was prescribed to each patient and after purgation with magnesium salt seven and two adult worms of Echinostoma cinetorchis in respect were recovered from patients. The first case was a 54-year-old male residing at Chungju city in Chungbuk province. He was hospitalized because of severe weight loss and frequent urination. The second case was a 71-year-old male residing at Chungsun-kun in Kangwon province, and hospitalized due to suspected lung cancer. The average size of the eggs found in the stools was 98 x 63 micrometer (the first case) and 100 x 67 micrometer (the second case) respectively, and total nine worms collected were identified as E. cinetorchis.

Experimental and epidemiological studies on the life cycle of Echinostoma hortense Asada, 1926 (Trematoda:Echinostomatidae)

Recently there have been some reports on human infections of Echinostoma hortense in Korea. It was found that a few species of freshwater fishes were playing the role of the second intermediate host of E. hortense. However, molluscan intermediate host has not been identified yet in Korea. The present study aimed to establish the life cycle of E. hortense in laboratory. Experimental studies such as egg production from the rat, development of the eggs in vitro, exposure of miracidia to freshwater snails, shedding pattern of cercariae from infected snails, morphology of cercariae, cercarial infection to the second intermediate host and infection of metacercariae to the difinitive hosts were done. In addition, epidemiological surveys on the infection status in inhabitants and house rats, and on the natural infection of larval echinostomes in the snails and fishes were carried out along the South Hangang-river. The results obtained were as follows: The eggs deposited from adults in physiological saline were cultivated at room temperature (20-24C). The miracidia were firstly observed on 8 days after cultivation, and 85.5 per cent of the eggs contained the mature miracidia on 11 days after cultivation. More than 90 per cent formed the miracidia when cultivated at temperature 22-27C. Hatching of the miracidia began on 12 days after cultivation and continued for a week. The size of the miracidia was 103.0 x 51.4 micrometer in average. The motility of miracidia were active up to 8 hours after shedding, but they were all dead within 10 hours after shedding. A freshwater snail, Radix auricularia coreana was cultivated in aquaria. A hatched F1 snails from the egg masses were exposed to 20 miracidia respectively. Escape of cercariae started on 15 days after infection. Radix auricularia coreana was experimentally identified as the first intermediate host of E. hortense in Korea. Cercarial shedding started on 15-20 days after infection by snail, continued for about 10 days (8.8 days in average). Infected snails were dead within 32 days after the miracidial infection. About 1,335 cercariae (328-1,994) per snail were shed in its life, and 119 cercariae in average per snail per day were shed. The cercariae were motile for more than 24 hours, and then squirming at the bottom until death. The body and tail sizes of cercariae were 356 x 186 micrometer and 510 x 68 micrometer in average, respectively. The rediae parasitized in the snail hosts were found mainly around the pericardial regions, and their size was 1,575 x 258 micrometer in average. The numbers of developing cercariae in a mature redia were 14 in average (7-20 in range). The numbers of rediae in a snail were 102 in average on 15 days after miracidial infection and 221 in average on 28 days. Three uninfected Misgurnus anguillicaudatus, less than 6.5 cm long were used in for the cercaria1 infection. They were all exposed with 755 cercariae, and examined at 5-day intervals starting from 10 days after infection. All the fihes were infected with metacercariae of E. hortense and a total of 275 was found infected (36.4 per cent). The metacercariae were fed to rats and the adult worms were obtained on 15 days after infection. The infected rats began to deposit the eggs on 11 days after infection. The number of eggs deposited per day per worm (EPD/worm) was 400-500 on 3 weeks after infection and was increased to 1,000-1,500 on 4 to 17 weeks, then decreased to 800 on 2l weeks after infection. A total of 745 stool specimens collected from 576 male and 169 female residents of 8 different villages along South Hangang basin was examined. Out of 745 specimens, the eggs of Echinostoma sp. were found in 2 cases (0.3 per cent). Of 34 house rats one showed egg-positive (2.9 per cent). Total 971 Radix auricularia coreana collected from 7 sampling stations were examined for shedding of cercariae. Three snails (0.3 per cent) shed the cercariae of E. hortense. A total of 119 out of 542 freshwater fishes (22.0 per cent) had the metacercariae of E. hortense. The fishes parasitized with the metacercariae were 4 out of 14 examined species. The infection rate of 4 species were 34.1 per cent (106 out of 311) in Misgurnus anguillicaudatus, 30.4 per cent 7 out of 23) in Misgurnus mizolepis, 4.3 per cent (2 out of 46) in Moroco oxycephalus and 22.2 per cent (4 out of 18) in Odontobutis obscura interrupta. In summarizing the above results, the first intermediate host of E. hortense was found as Radix auricularia coreana in Korea. Also it took about 46 days for the shortest completion of a life cycle of E. hortense in summer; that is, 10 days for miracidial development in eggs, 15 days for cercarial development in the snail, about 10 days for metacercarial development in the second intermediate hosts, 11 days for the maturation as the adults in the definitive hosts. The natural infection rates of E. hortense in the intermediate hosts were relatively high but those in the definitive hosts were low in the middle areas of South Hangang basin.

Two cases of natural human infection by Echinostoma hortense and its second intermediate host in Wonju area

Two cases of human Echinostoma hortense infection and their probable infection source were identified by praziqantel (Distocide) treatment of the patients and by examining two kinds of fresh water fish which were eaten raw by them. The result of the research can be summarized as follows: The patients, each aged 31 and 30, were residing in the same house in Wonju City, Kangwon Province. The first case was hospitalized due to epidemic hemorrhagic fever (E.H. fever) and the second case was healthy but had slight degree of abdominal pain and diarrhea from time to time. In the stool examination, eggs of E. hortense (114.3 x 71.0 micrometer average from the first case and 119.1 x 68.3 micrometer average from the second) were found. By administering single dose of praziquantel (10~15 mg/kg) and purgation with magnesium salt to them, six adults of E. hortense were collected from the diarrheal stools of the second case. By examining 84 Moroco oxycephalus and 20 Carassius carassius which were captured at the place where the two patients had captured and eaten the fresh water fish, the metacercariae of Echinostoma sp. were found from 3 (3.5 percent) M. oxycephalus. After the experimental infection of 3 isolated metacercariae to one albino rat three adults of E. hortense were recovered. By the present study, the two patients revealing the echinostomatid eggs in their stools were proven to be infected with E. hortense and to be the second and third human cases of this fluke infection in Korea. Moroco oxycephalus harboured the metacercariae of E. hortense and appeared to be a new second intermediate host.

Echinostoma hortense metacercariae naturally encysted in Odontobutis obscura interrupta (a freshwater fish) and experimental infection to rats

The metacercariae of an echinostomatid fluke were detected from a freshwater fish, Odontobutis obscura interrupta caught from the Seom river system, Wonseong-gun, Kangwon-do, and experimenally infected into rats to obtain the adult worms for the species identification. A total of 32 metacercariae was detected from 10 fishes (27.8 percent) out of 36 O. obscura interrupta caught from the river. The average size of metacercariae was 153.4 x 149.0 micrometer. Also, it was uniquely specific that thickened membrane was formed around the metacercarial cyst wall. The rats orally infected with those metacercariae were sacrificed 20 days after infection to get the adult worms. The mean length and width of the adult worms were 0.75 cm and 0.13 cm, respectively. The number of collar spines on circumoral disk was 26 to 28, and the end group spines at lateral sides of the oral sucker were 4 on each side. The echinostomatid flukes observed in this study were all identified as Echinostoma hortense according to the morphologies of the cirrus sac, ovary, vitellaria and testes of the adult worms and the shape of eggs. On the other hand, O. obscura interrupta is one of the fresh-water fish that are preferably eaten raw by the rural inhabitants. Although no human case of E. hortense infection by eating O. obscura interrupta has been experienced yet, the possibility is strongly suggested in this study.

Helminthes infections in the small intestine of stray dogs in Ejungbu City, Kyunggi Do, Kerea

One hundred and two stray dogs in Ejungbu City of Kyunggi-Do, Korea were examined to reveal out the degree of natural helminthic infection of small intestine. Helminthes were collected at autopsy, by scraping the intestinal contents. The collected worms were classified by their morphological characteristics. Out of 102 examined, 72 dogs were infected with any helminthes. The common helminthes were Dipylidium caninum (47 percent), Ancylostoma caninum (26 percent), Toxascaris leonina (16 percent) and Toxocara canis (13 percent). Taenia pisiformis (9 percent), Echinostoma hortense (4 percent), E. cinetorchis (2 percent), Spirometra mansoni (2 percent) were also found. One dog was incidentally found to be infected with Clonorchis sinensis. The prevalence of Toxascaris leonina was relatively high in this study over Toxocara canis, and its significance was discussed. Dogs were firstly described as the reservoir hosts of Echinostoma hortense and E. cinetorchis in Korea.

Evaluation of anthelmintic treatment of Enterobius vermicularis infection in highly endemic population by prolonged observation

To evaluate the efficacy of anthelmintic treatment of Enterobius vermicularis in highly endemic population, total 82 children in two orphanage institutes were divided into 4 groups and treated with placebo, 5 mg/kg of pyrvinium pamoate, 100 mg of mebendazole and 10 mg/kg of pyrantel pamoate respectively. Total 4 anal swabs were taken from each child before treatment and the even distributions of positive rate and consecutive results between groups were considered. Follow-up swabs were taken 8 times up to the 40th day after treatment. After remarkable and significant reduction of positive rates up to 19-27th day after treatment in respective groups, the remarkable egg positive conversions were observed 3-4 weeks after treatment. The positive conversion was the earliest and the most remarkable in pyrantel-treated children and the slowest and the least remarkable in mebendazole-treated cases. Also found was that the figures of negative conversion were different with statistical significance between two categories of cases, consecutively positive and alternately positive cases of pre-treatment swabs. This means that the conventional indices of cure rate in E. vermicularis infection may be variable by the selection of subjected cases. Above results mean that the spectrum of susceptible pinworms according to the developmental stages are different between currently available drugs, and the ability to remove pinworms completely in certain developmental stage are also different between chemotherapeutics. These results suggest the need of interval chemotherapy of Enterobius vermicularis infection in heavily infected cases of in highly endemic population to achieve the complete eradication of whole range of pinworms in intestine.

Relationships between the results of repeated anal swab examinations and worm burden of Enterobius vermicularis

To relate the results of repeatedly undertaken anal swabs to worm burden of Enterobius vermicularis in a highly endemic community, 193 rural schoolchildren, divided into 4 groups, were examined daily by Scotch-tape anal swab method, 1, 2, 3 and 4 times respectively. All of the schoolchildren were treated with pyrantel pamoate 10 mg/kg body weight exactly after the last anal swab in each group disregard the results. And all of the expelled E. vermicularis were collected and counted. It was found that 68.8% of total anal swabs were positive and the collection rate of E. vermicularis was 90.7% with average worm burden, 17.0, in surveyed children. From the analyses of the obtained data, following three inferences were derived. The consecutive postive findings of anal swabs could not reduce the possibilities of detecting light worm burden cases when the anal swabs were undertaken daily up to 4 times. The possibilities of detecting the heavy infection cases were found in consecutively positive categories of anal swab and the presence of negative result(s) of anal swab during the consecutive examinations did denote the reduced possibilities of detection heavy infection. The consecutive negative findings in anal swab have tendenicies reducing the possibilities of detecting heavy worm burden cases. Above results were highly suggestive that the processes of infection loss in E. vermicularis were taken place continuously, allowing daily small allotments of discharge of fully gravid worms in heavy infection cases and massive discharge in a very short period of time is practically rare event.

Histochemical study on trematodes - Distribution of carbonic anhydrase activity

The purpose of the present study is to demonstrate the distribution of carbonic anhydrase pattern in the various termatodes (Fasciola gigantica, Paramphistoma orthocoelium, Paragonimus westermani) by means of Kurada staining method, and to correlate these findings with the histochemical data and harboring location. The results are summarized as follows: In Fasciloa gigantica, carbonic anhydrase activity was positive in the vitelline gland cells and eggs in the uterus. In Paramphistoma orthocoelium, carbonic anhydrase activity was positive in the vitelline gland cells and eggs in the uterus. In Paragonimus westermani, carbonic anhydrase activity was positive in intestinal mucous membrane, vitelline gland cells and eggs.

Parasitological studies of Korean forces in South Vietnam I. Examination of blood films on malaria patients

A parasitological study was performed with 452 malaria patients evacuated from South Vietnam by examinations of their peripheral blood. Results were as follows: The peripheral blood examinations revealed that 52.0% of the examined have parasitemia, of which 95.3% was P. falciparum, one case of P. vivax and the other 10 patients were mixed infected. Neither P. malaria nor P. ovale were found. A total of 1,500 thick and thin blood films was prepared and 707 slides of them (47.1%) showed positive. In P. falciparum, ring forms were found most frequently and the next was gametocytes. Eighty slides (50%) showed mixed together with both ring form and gametocytes. All of the erythrocytic stages were seen in three slides of P. vivax. Weekly periodical examinations showed 233.8 parasite density every 1,000 W.B.C count in average, while occasional at fever attacks 531.7.Size of gametocytes in P. falciparum was 9.31(+/-0.89) by 2.16(+/-0.53) in macrogametocyte and 6.61(+/-0.82) by 2.51(+/-0.35) in microgametocyte. Their sex ratio was 100 : 92. Repeated blood examinations showed increased detection rates. The positive rate of parasitemia was 52.0% in single examination, increasing in succession with repetitions.

The prevalence of intestinal parasitesin ROKA soldiers at Won-Ju area

A survey on the prevalence of intestinal parasites was performed during the period from April to June of 1969, to evaluate the present status of parasitic infections in ROK Army soldiers. Stool specimens of 1,0l2 soldiers were collected from a camp located in Won-Ju area, and examined by the method of formalin-ether sedimentation technique. For protozoan cysts, examined slide was stained with Lugol's iodine solution and for eggs of Enterobius, the Graham's scotch cellulose tape anal swab technique was applied. The results obtained in this survey were as follows: Of the 1,012 soldiers examined, 95.0 percent were found infected by one or more intestinal parasites and 28.7 percent were found positive for protozoan cysts. The positive rates of each parasites were; A. lumbricoides 61.0 percent, T. trichiurus 73.4 percent, hookworm 17.5 percent, T. orientalis 9.5 percent, E. vermicularis 0.1 percent (from stool specimen), C. sinensis 8.8 percent, M. yokogawai 1.1 percent, Taenia sp. 1.0 percent (from stool), H. nana 0.3 percent and E. histolytica 7.4 percent. E. coli 12.6 percent, E. nana 5.9 percent, I. buetchlii 0.7 pecent, G. lamblia 6.1 percent, and C. mesnili 0.8 percent. From the anal swabs, eggs of Enterobius were recovered in 2.6 percent, and eggs of Taenia sp. showed positive rate of 1.5 percent.