No abstract available.
Clonorchis sinensis*

The survival ability of the larve of Clonorchis sinensis in raw fish dish prepared by traditional culinary method in NghiaLac commune, NghiaHung District,NamDinh province and the larve of Paragonomus heterotrimus in grilled crabs processed in KhanhHoa commune, LucYen district, YenBai province was investigated..In this raw fish dish, 93-95% of the microcerca of Clonorchis sinensis and in this grilled crab, 23,3-65% of microcerca had been living
Fishes ; Clonorchis sinensis ; epidemiology

A survey concerning the infestation of clonorchis sinensis in human was conducted in 4 communes of Ninh Binh and Nam Dinh provinces, from each, 100 households with their members of above 6 years old of age were enrolled randomly. Results showed a prevalence of 31.3 – 37.3% in Nam Dinh and 22.5% in Ninh Binh epidemic areas. The prevalence in male subjects was higher than in female (45.5 –47.6% versus 10.9 – 26.1%). The age group of 40-49 years old had had the highest prevalence (51.9%). There, 35.9 – 80.4% of people had consumed raw fish.
Opisthorchis ; Epidemiology ; Clonorchis sinensis

The survival ability of the larvae of Clonorchis sinensis in raw fish dish prepared by traditional culinary method in Nghia Lac commune, Nghia Hung District, Nam Dinh province and the larvae of Paragonimus heterotrimus in grilled crabs processed in Khanh Hoa commune, Luc Yen district, Yen Bai province was investigated. In this raw fish dish, 93-95% of the microcerca of Clonorchis sinensis and in this grilled crab, 23.3-65% of microcerca had been living
Clonorchis sinensis ; Fishes ; Paragonimus

Clonorchis sinensis, the most widespread liver fluke of the parasite localized in liver and biliary tract, threats at least 19 millions of people in the world. The distribution of C. sinensis over almost all China (except the West-Northern area) and Taiwan, Korea, Japan and Northern regions of Vietnam. Since the first record of C. sinensis in Vietnam last century, up to date the disease has been reported from at least 12 provinces of the country. At the certain epidemiological foci, the rate of C. sinensis infection has not decreased but, in inverse, it seems to have tendency to increase. This review follows the worldwide and local literature in the domain to provide a brief summary on the distribution and status of C. sinensis infection and in the world, particularly in Vietnam.
Clonorchis sinensis ; Epidemiology

A region of mitochondrial cytochrome oxidase 1 gene (coxl) for Clonorchis sp samples from the provinces of Thanh Hoa and Nam Dinh, and Opisthorchis sp from human in Phu Yen province, Vietnam was analyzed by PCR. Nucleotide sequence of these coxl fragments was used to compare with Opisthorchis viverrini, strain Khon Ken (Thailand) and Clonorchis sinensis sequences originated from China and Korea. The results revealed that nucleotide sequence of Opisthorchis sp from Vietnam had absolute homology to O. viverrini (Thailand) but different from C. sinensis (from China and Korea). Clonorchis sp from Vietnam was similar with Clonorchis sinensis from China and Korea. Opisthorchis sp isolated in Phu Yen is, thus, molecularly indentified as Opsithorchis viverrini and Clonochis sp in Thanh Hoa and Nam Dinh is Clonorchis sinensis. Two species are different in morphology and molecular level.
Mitochondria ; Clonorchis sinensis

No abstract available.
Clonorchiasis* ; Clonorchis sinensis

4826 stool samples collected from 5 communes were examined by Kato- Katz technique. The infection rate of clonorchis sinensis was 33,9% in average (22,5% to 37,3%). The infection rate in male was higher than in female by 4 times and highest in 40- 49 age group (51,9%). The habit of eating raw fish is very common in this area (55,6%- 80,4%). The adult worms from patients in these study sites were identified as clonorchis sinensis
Clonorchis sinensis ; epidemiology ; Fishes ; Helminths

In order to determine the epidemiological patten of the liver fluke, Clonorchis sinensis, the locality where the snail, Parafossarulus manchouricus, is abundant, the infestation rates for the cercarial and metacercarial larvae of digenetic trematodes in the snail and fish hosts, and the prevalence of Clonorchis sinensis among the residents in the vicinity of river Taewha, Kyungnam Province, Korea were studied from March 1979 to September 1980. Four snail habitats were found in the river Taewha. The population density of the snail per square meter of the habits ranged from 10 to 500, with an average of 150. Among the 4 snail habitats, three, Baek-cheon, Sa-yeon and Taewha had snails infected with the cercaria of Clonorchis sinensis, and the proportion of infested snails in the three habitats was very low, the average being 0.59 per thousand. Four species of fresh-water fish, the bullhead, Coreobagrus brevicorpus, the Korean shiner, Gnathopogon atromaculatus, the flat bitterling, Paracheilognathus rhombea, and the striped shiner, Pungtungia herzi among ten species of fish examined harbored the metacercaria of Clonorchis sinensis. The intensity of infestation with the cyst of Clonorchis sinensis in the four species of fish was low. The approximate number of the cysts per gram of flesh was between 3.5 in Paracheilognathus rhombea and 21.5 in Gnathopogon atromaculatus. Seven kinds of laval tremathodes, Clonorchis sinensis, Cyathocotyle orientalis, Echinochasmus species, Exorchis oviformis, Metacercaria hasegawai, Metagonimus yokogawai and Metorchis orientalis were found from ten species of fish examined. In general, the infestation rates for the encysted larvae of digenetic trematodes varied from fish to fish. The infection rate for Clonorchis sinensis among the residents in the vicinity of river Taewha was relatively high, 22.2 percent by the formalin-ether sedimentation technique, and the difference in the rate of infection between males and females found to be siginificant(t>2). Of these, the rate was 12.4 per cent in 483 elementary school children and 17.7 percent in 761 middle and high school students. The results obtained in the present study indicate that endemic foci of Clonorchis sinensis exist in the river Taewha and the prevalence of the liver fluke among the residents is still high.
parasitology-helminth-trematoda ; Clonorchis sinensis ; epidemiology

The present study was undertaken to observe the morphological changes of Clonorchis sinensis obtained from experimentally infected rats treated with praziquantel (Biltricide) which is a new anthelmintic agent with high activity against a broad spectrum of cestode and trematode species. For this study, the rats were infected experimentally with about 50 metacercariae of C. sinensis and were given praziquantel a single dose of 600 mg per kg of body weight at 5 weeks after infection. The Clonorchis worms were isolated from the bile ducts of the rats which were autopsied on the 4th day after treatment. After isolation the parasites were observed their shape and motility in the medium of 37 C physiological saline solution, and then the fine structure of the tegument of C. sinensis was studied by means of light, scanning and transmission electron microscope. The findings of the observation were compared with those of untreated parasites. The results are as follows: All the isolated worms moved actively in the medium of physiological saline solution (37 C). A majority of the parasites obtained from the treated rats showed a large balloon shaped structure on the surface between oral and ventral suckers. But such structure has never seen in the parasites obtained from control rats. By the scanning electron microscopic observation, the regular pattern of the tegumental ridges was significantly changed on the outer surfaces of parasites obtained from the treated rats as compared with those of the control rats. By the transmission electron microscopic observation, the numerous mitochondriae in the syncytial tegumental layer of the treated parasites appeared to be degenerated and formed small vacuoles, and the tegumental ridges were also degenerated and showed somewhat flattened. In the parasites obtained from the treated rats, a different size of vacuoles interspersed in the distal part of the syncytial tegument and also in subepithelial region of the urinary bladder. These vacuoles are fused each other and lead to the disruption of the apical region of syncytial tegument along the basement layer. Finally the basement layer was dislocated. So that the tegumental layer appeared as a large balloon.
parasitology-helminth-trematoda ; Clonorchis sinensis ; chemotherapy