• Parasites, Hosts and Diseases
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• v.44 no.4 s.140
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• pp.343-353
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• 2006

Giardia intestinalis infections arise primarily from contaminated food or water Zoonotic transmission is possible, and at least 7 major assemblages including 2 assemblages recovered from humans have been identified. The determination of the genotype of G. intestinalis is useful not only for assessing the correlation of clinical symptoms and genotypes, but also for finding the infection route and its causative agent in epidemiological studies. In this study, methods to identify the genotypes more specifically than the known 2 genotypes recovered from humans have been developed using the intergenic spacer (IGS) region of rDNA. The IGS region contains varying sequences and is thus suitable for comparing isolates once they are classified as the same strain. Genomic DNA was extracted from cysts isolated from the feces of 5 Chinese, 2 Laotians and 2 Koreans infected with G. intestinalis and the trophozoites of WB, K1, and GS strains cultured in the laboratory, respectively. The rDNA containing the IGS region was amplified by PCR and cloned. The nucleotide sequence of the 3' end of IGS region was determined and examined by multiple alignment and phylogenetic analysis. Based on the nucleotide sequence of the IGS region, 13 G. intestinalis isolates were classified to assemblages A and B, and assemblage A was subdivided into A1 and A2. Then, the primers specific to each assemblage were designed, and PCR was peformed using those primers. It detected as little as 10 pg of DNA, and the PCR amplified products with the specific length to each assemblage (A1, 176bp; A2, 261 bp; B, 319 bp) were found. The PCR specific to 3 assemblages of G. intestinalis did not react with other bacteria or protozoans, and it did not react with G. intestinalis isolates obtained from dogs and rats. It was thus confirmed that by applying this PCR method amplifying the IGS region, the detection of G. intestinalis and its genotyping can be determined simultaneously.

• Korean Journal of Veterinary Service
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• v.43 no.1
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• pp.23-29
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• 2020

Hepatitis E Virus (HEV) infection is a worldwide disease and the primary cause of acute viral hepatitis in the world. It can be isolated from many different species including pigs. HEV is a zoonotic pathogen and foodborne disease. The main animal reservoir is domestic pigs. It is usually asymptomatic in pig but it is a public health concern, causing acute hepatitis in humans of varying severity. This study focused on the presence of HEV in pig and pork product. One hundred feces and one hundred fifty serum samples were randomly collected from pigs in slaughterhouses in Gwangju from November in 2018 to February in 2020. In addtion, seventy-five pork products were collected from markets in Gwangju. Feces and pork product samples were examined for the presence of HEV RNA using an reverse-transcription realtime PCR (RT-qPCR) assay. Serum samples were tested for the presence of HEV-specific IgG antibodies using Enzyme-linked immunosorbent assay (ELISA). HEV antigen and antibody positive rates were 3.0% (3/100) and 19.3% (29/150), respectively, in Gwangju and nearby areas such as Jeonnam and Jeonbuk. However, HEV antigen was not detected from any of pork product in this study. In conclusion, the prevalence of HEV should be continuously monitored because HEV was sporadically detected in Gwangju and nearby areas.

• Journal of Veterinary Clinics
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• v.31 no.1
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• pp.6-10
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• 2014

Siberian Roe deer which inhabits Jeju Island is unique native species. Most of all the roe deer infect a lot of ticks, which can affect its population directly and can act as a vector to spread vector-borne diseases. The purposes of this study were to identify the ticks and detect the piroplamsosis on the roe deer in Jeju island. We collected ticks and blood samples in 23 roe deer rescued and treated at the Jeju Wildlife Rescue Center. As a result, we identified the one species of ticks, Haemaphysalis longicornis in roe deer and detected the closely related to Theileria luwenshuni in all blood samples (100%) and 8 pooled ticks (34.8%). These results indicate that there may be a high prevalence particularly of T. luwenshuni infection in Jeju wild roe deer and H. longicornis is a major vector of these diseases. It suggested that Jeju roe deer may act as reservoirs for these zoonotic pathogens.

• Journal of Veterinary Clinics
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• v.27 no.1
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• pp.1-5
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• 2010

Enterocytozoon bieneusi, a microsporidian species, has emerged as an opportunistic pathogen in AIDS patients. This organism has also been identified in a wide range of animals, and the zoonotic potential of human infections is of particular interest. This study revealed that this organism was found with relatively high prevalence in feces of asymptomatic cattle in Korea. Fecal specimens were obtained from a total of 1,720 cattle in a slaughterhouse located in Chungnam province, Daejeon city and Chonbuk province. After removal of fecal debris by sieving and density gradient centrifugation, samples were examined by microscopic examination and then nested polymerase chain reaction (PCR). Microscopic examination with the modified trichrome staining for the fecal specimens revealed 194 (11.28%) positive calves for microsporidia spore. PCR using the specific primer for E. bieneusi revealed 79 (4.59%) positive calves. The infection ratio of microsporidia was higher in March than other season.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.13-19
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• 2012

To determine the status of Korean molluscs infection and relation with climate change of Korean peninsula, references were reviewed. Wild animals serve as intermediate, reservoirs and paratenic hosts to zoonotic parasites of human beings. Trematode are common parasites of molluscs and almost all trematodes infect mollusks as the first host in the life cycle, and most have a complex life cycle involving other hosts. The significance of auxiliary hosts to the ecology of the parasite has not been proper discussion. There is increasing concern as to the impact of climate change on the epidermiology of many parasitic diseases. A total of 21 species for snail transmitted parasites from Korean molluscs has been reviewed. Among them, 15 species was aquatic mollusks and 6 species for marine mollusks. Maximum infections belonged to Semisulcospira livertina had 11 kind of parasite pathogenic organisms, including Paragonimus westermani, Metagonimus yokogawai, Centrocestus armatus, Notocotylus magniovatus, Centrocestus formosanus, incerte cercaria, nipponensis cercaria, Yoshidae cercaria, cristata cercaria, innominatum cercaria and Metagonimus sp. And 11 in Parafossarulus manchouricus including Clonorchis sinensis, Asymphylodora japonica, Cyathocotyle orientalis, Exorchis oviformis, Notocotylus attenuatus, Echinochasmus japonicus, Loxogenes liberum, Cercariae of Loxogenes liberum Type I, Cercariae of Loxogenes liberum Type II, Furcocercus cercariae (Family Sanguincolidae) and Cercaria of Mucobucaris, 10 in Semisulcospira sp. including Paragonimus westermani, Metagonimus yokogawai, Centrocestus armatus, Echinochasmus redioduplicatus, Notocotylus magniovatus, Cercaria incerte, Cercaria nipponensis, Cercaria yoshidae, paludinarum cercaria and Metagonimus sp., 7 in Koreanomelania globus including Pseudexorchis major, Cercaria of parapleurolophocercous type, Metagonimus sp. (A & B), Cercaria nipponensis, Cercaria inserta and Cercaria yoshidae. Also, Tapes philippinarum have 3 pathogenic organisms including Cercariae tapidis, Cercariae furcocercus and Parvatrema sp. In particular, under climatic extremes such as floods and drought, aquatic molluscs may play a more prominent role in parasite transmission in the future.

• Parasites, Hosts and Diseases
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• v.60 no.1
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• pp.65-71
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• 2022

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a zoonotic, tick-borne RNA virus of the genus Bandavirus (Family Phenuiviridae), mainly reported in China, Japan, and the Republic of Korea (Korea). For the purpose of this study, a total of 3,898 adult and nymphal ticks of species Haemaphysalis longicornis (94.2%), Haemaphysalis flava (5.0%), Ixodes nipponensis (0.8%), and 1 specimen of Ixodes ovatus, were collected from the Deogyusan National Park, Korea, between April 2016 and June 2018. A single-step reverse transcriptase-nested PCR was performed, targeting the S segment of the SFTSV RNA. Total infection rate (IR) of SFTSV in individual ticks was found to be 6.0%. Based on developmental stages, IR was 5.3% in adults and 6.0% in nymphs. The S segment sequences obtained from PCR were divided into 17 haplotypes. All haplotypes were phylogenetically clustered into clades B-2 and B-3, with 92.7% sequences in B-2 and 7.3% in B-3. These observations indicate that the Korean SFTSV strains were closer to the Japanese than the Chinese strains. Further epidemiological studies are necessary to better understand the characteristics of the Korean SFTSV and its transmission cycle in the ecosystem.

• Journal of fish pathology
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• v.30 no.2
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• pp.89-96
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• 2017

The majority of freshwater ornamental fish are imported and distributed domestically, causing high risk of exposure to exotic pathogens and drug resistant bacteria in Korea. Aeromonas hydrophila is known as a common species of fresh water bacteria and opportunistic fish pathogen, as well as a species causing zoonotic infection. In this study, we isolated motile aeromonads from various imported freshwater ornamental fish and studied the characters of the isolates. Imported freshwater ornamental fish were purchased on day 1 after the fish were deposited in the aquarium. Bacteria were isolated from the liver, kidney and spleen of fish using 0.5% NaCl containing tryptic soy agar medium. Bacteria were grouped on the basis of their morphological characteristics. The colonies with clear zone on starch-ampicillin agar (SA agar) were tentatively identified as Aeromonas spp. Two hundred and twenty-six strains, about 70% of total isolates were assumed to be Aeromonas spp. Nine isolates were further identified based on the result of the API 20E test and PCR using primers specific for A. hydrophila 16S rRNA gene. The isolates were identified as A. hydrophila and the API 20E test showed differences in trisodium citrate, D-sucrose, D-melibiose, amygdalin and L-arabinose availability between the nine isolates and standard A. hydrophila. The susceptibilities of the isolated bacteria to 10 antibacterial agents were confirmed by the disk diffusion method. Isolated strains were found to be resistant to amoxicillin and ampicillin and sensitive to florfenicol. However, 7 isolates showed multiple drug resistances to erythromycin, oxytetracycline, nalidixic acid etc. Pathogenicity of the isolates was determined by the artificial challenge test on goldfish (Carassius auratus). Three isolates caused 60 ~ 80% mortality in goldfish within 5 days after the initiation of challenge. These results indicate that multiple drug resistant, highly pathogenic and exotic A. hydrophila can spread to domestic aquarium and the preventive treatment of fish before sale is necessary.