Background: Mosquitoes and pigs play important roles in maintaining and increasing the Japanese Encephalitis (JE) virus in nature and which is then transmitted to humans. Thus, surveillance of the JE infection frequency in the pig population may predict the human JE cases. \r\n', u'Objectives: The study aimed to determine IgG antibody against the JE virus in the pig population in Hanam province \r\n', u'Subjects and methods: The study included 1791 pig serum samples collected from 3 districts of Hanam province from Apr 2006 to Mar 2007. GAC-ELISA technique was used to determine the JE virus infection in the swine population.\r\n', u'Results: The average positive rate in pig population was 34.9 % (626/1791); with the highest frequency occurring in the summer (37.7%- 84.0 %), co-incident with the JE season in Northern Vietnam. On the contrary, in winter JE case are rare, frequency of IgG antibody against JE virus in the swine population was low, ranging from 9.2% to 22.0.%. \r\n', u'Conclusions: These results have shown the ecologically close relationship between the amplification of the JE virus in the swine population, vector and JE cases in northern Vietnam. \r\n', u'
Japanese encephalitis ; pig population ; GAC-ELISA.

Thirteen guinea pigs and 23 rabbits were challenged with 300 metacercariae of Clonorchis sinensis each and the recovery of adult worms and egg counts in feces were compared at 11-13 weeks post-infection in guinea pigs and at 7-9 weeks post-infection in rabbits. The recovery rate of adult worm was 23.5 percent in guinea pigs and 20.l-30.5 percent in rabbits. The mean E.P.G. of these animals in above period of infection was 106 in guinea pigs and 121 in rabbits. When one hundredth of E.P.G. was expressed as X and the number of adult worms as Y, the relationships between X and Y were as follows; Y=0.8X+10.8 in guinea pigs and Y=0.7X+6 in rabbits.
parasitology-helminth-trematoda ; Clonorchis sinensis ; guinea pig ; rabbit ; egg

The present study was undertaken to observe the changes of hepatocyte and biliary epithelium in the liver of guinea pigs infected with C. sinensis. Ten guinea pigs infected with 500 metacercariae of C. sinensis each were reared for 11 weeks. After sacrifice, the liver tissues were processed both for conventional light microscopy and for electronmicroscopy. The following results were obtained by light and electronmicroscopic observation of these tissue preparations. The dilatation of bile ducts with chronic inflammatory cell infiltration and fibrosis, and flattening of lining epithelium were observed by light microscopy. Bile duct showed a single low columnar or cuboidal epithelium and subepithelial small round cell infiltration. Papillary proliferation, adenomatous hyperplasia and increase of goblet cells in the subepithelial glands were also noted in some areas of bile ducts. Occasionally, small fibrous nodules in the portal tract replacing bile ducts, surrounded by a heavy infiltrate of small round cells and neutrophils were observed. On light microscopic examination, no cellular damages were seen in the liver cells except mild fatty degeneration. Electronmicroscopic examination of the biliary epithelium revealed increased mucin granules, cytoplasmic projection into lumen, decreased microvilli and obstruction of bile canaliculi. Indistinct and/or irregular appearances of intercellular lateral interdigitation were observed in most of biliary epithelium. On the electronmicrographs of hepatocytes, dilation of endoplasmic reticulum(ER) and destruction of cristae in some mitochondriae were prominent features. Disappearance of cytoplasmic organells and dilatation of bile canaliculi were also monitored. Endothelial cells in the sinusoids were remained intact.
parasitology-helminth-trematoda ; Clonorchis sinensis ; guinea pig ; pathology ; bile duct ; ultrastructure-electronmicroscopy ; fibrosis ; hyperplasia ; goblet cell

The histochemical study, especially the demonstration of alkaline phosphatase and acid phosphatase was carried out in order to differentiate ascarides of human and pigs. The experimental material were obtained from naturally contaminated men and pigs. As the histochemical staining methods the Gomori's was applied for acid phosphatase and Takeuchi and Takami's for alkaline phosphatase. The results obtained were summerized as follows : In the pig's ascarides, alkaline phosphatase was richly found in the subcuticular tissue, lateral line, median line, strial zone and epithelial cells of the intestine, epithelial cell and basal membrane of the ovary, the same part of the uterus and also in eggs. Acid phosphatase in the pig's ascarides were distributed in the same part as alkaline phosphatase. It, however, was darker brown in the soft tissue of the lateral line, epithelium of excretory canal, median bundle, whole zone of the intestine and intestinal contents. In the human ascarides, the alkaline phosphatase was distributed in the testes and the parts where the acid phosphatase was found in the pig ascarides. The acid phosphatase in the human ascarides was demonstrated in the subcuticular tissue, soft tissue of lateral line, epithelium of excretory cells, strial zone, transparent zone, granular zone and epithelial zone of esophagus and intestine, ovary, ova in the uterus, epithelial cell and basal membrane of the uterus and in testes. In the pig's ascarides, the area of distribution of alkaline phosphatase was restricted, but that of acid phosphatase was wider. In human ascarides, the area of distribution of alkaline phosphatase and acid phosphatase was not significantly different, but in some part showed slight difference. Above mentioned finding suggest that the distribution of phosphatase could be utilized for the differentiation of ascarides of human and pig.
parasitology-helminth-nematode-Ascaris lumbricoides ; Ascaris suum ; histochemistry ; differentiation ; alkaline phosphatase ; acid phosphatase ; animal ; human ; pig

To observe the possibility of human visceral larva migrans due to eating of raw liver of domestic animals, especially of cattle, and also to serve as a good reference for adequate sanitary measures, the investigation survey was carried out from May 1975 to May 1976. From the subjects of a l,048 inhabitants (male 558, female 490) in five localities including two Provinces and three different cities, food habit was studied by questionnaire mannual. Larvae isolated from liver tissues of cattle, and pig were identified. Experimental observation on the chicken and mice infected with Toxocara canis was undertaken to draw a assumption of possibility inducing human visceral larva migrans. The results obtained from the present study are summarized. A part of Korean people has the habit to eat the livers of cattle, fowl, pig and dog raw. Eating rate of raw beef liver was 37.8 percent out of l,048 inhabitants, and its rate was higher markedly in male(57.7 percent) than in female (15. 1 percent), and the highest rate among the group of 31-40 years old. Eating rate of raw liver of fowl was 5.9 percent, pig 5.3 percent, and dog 2.5 percent. Larva recovery rate from beef liver was 11.8 percent out of 195 samples and 72.0 percent of total detected 1arvae were identified as Toxocara(=Neoascaris) vitulorum. From pig liver, larvae of nematoda were found in 6.4 percent out of 109 samples but no larva was detected from 120 fowl livers. Larvae detected from one-half of tissues and organs of infected chicken with about 2,000 Toxocara canis eggs were 8-245 in number, and 85-100 percent of recovered larvae were from their 1iver tissues. Toxocara canis larvae, 45, 31, 42 and 23 in number at 3rd, 14th, 25th and 55th day in one-half of the tissues and organs after infection respectively, were demonstrated from the mice infected with 500 larvae collected from infected chicken liver. Most of the larvae were recovered from the carcass of the mouse. It was approved the larvae isolated from chicken possess infectivity to the mice. Typical eosinophilic granulomatous change was not observed in the liver tissue of the infected chicken at 20th day after infection. As it summarized above, the liver of various domestic animals is the favorite tissue for migration of nematodes larvae. Therefore, the possibility of human visceral larva migrans may be induced due to eating of raw liver of domestic animals.
parasitology-helminth-nematoda ; visceral larva migrans ; Toxocara canis ; liver ; cattle ; fowl ; pig ; dog ; mouse ; chicken ; infectivity

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