• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.505-513
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• 1995

Seventy wild rats were caught from Seoul city, Kyonggi, Kangwon, Honam, and yongnam provinces. All of them were in same species, Rattus norvegicus, except two R rattus from Kyonggi province. Seventy sera from wild rats were studied by immunofluorescent antibody assay for evidence of infection by spotted fever group rickettsia. The antidody prevalance was 37.14%(26/70) for spotted fever group rickettsia. The sero-prevalence rates for spotted fever group rickettsia antibody was the hightest in Kyonggi province with 55.56%(10/18), yongnam province with 50.00%(10/20), Kangwon province with 25.00%(2/8), Seoul city with 18.75%(3/16), and Honam province with 12.50%(1/8). The sero-positive rates difference between sexes were higher in female with 46.15%(12/26) than in male with 31.81%(14/44) for spotted fever group rickettsia. Twenty six of 68 Rattus norvegicus with antibody for spotted fever group rickettsia were in subadult with 50.00%(6/12), young adult with 38.89%(7/18), middle-aged adult with 35.29%(6/17), and old adult with 33.33%(7/21). No antibody was detected from R rattus.

• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.167-173
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• 2019

Rickettsial infections (Rickettsioses) are the causes of acute fever found in Thailand. It is classified as acute febrile illnesses transmitted by bloodsucking arthropod vectors (tick, flea, and chigger). This research investigated pathogens of scrub typhus in vectors from Bangkaew District, Phatthalung Province. A total of 303 pools of vector samples were ticks (Rhipicephalus sanguineus, R. microplus, and Haemaphysalis sp.), fleas (Ctenocephalides felis orientis, C. f. felis, and C. canis), and chiggers (Leptotrombidium deliense, Aschoschoengastia indica, Blankaartia acuscutellaris and Walchia disparunguis pingue) collected from reservoir hosts (dogs and rodents). The 17 and 56 kDa gene of Rickettsia causing scrub typhus were found in 29% of ticks and 98% of flea. DNA sequence analysis reveeled the detected strains were R. asembonensis and Rickettsia sp. cf1 and 5.The chiggers, 1%, were infected with Rickettsia strain TA763, a pathogen of scrub typhus.

• Korean Journal of Microbiology
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• v.30 no.2
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• pp.124-128
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• 1992

A total of 275 wild hats captured in Korea here examined 011 the possibility that they will harhor and spread the inkctious pathog.cns of Hantaan virus and Rickettsia. They possessed ontihotlies in 3.6'K) blood sera against Hantaan virus by the indirect in~~nunofluoresccnctec hnique and showed relatively high serum titers with a range of 16 to 1014X. whereus 13.7\ulcorner0 of them were positive to Rickettsia. dividing into 3.3% against R. ~.sur,~ugc~rnusllr.Ri.1 k, against R. siht)ric.n tick ~vphus,a nd 4.4% against R. thai tick pphus. respectively. 11 was first confirmed in Korean wild hats that arc infccted with Hantaan virus and Rickettsia agents. and play a role as vector.

• The Journal of Korean Society of Virology
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• v.28 no.1
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• pp.1-9
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• 1998

To study the relation between ectoparasite, Rickettsia and hanntan virus in bats, four order of Athropoda were collected from Rhinolophus ferrumequinum captured in Cheju and Eptesicus serotinus captured in Chungnamin from July 1989 to March 1998. Also antibody of Rickettsia and hanntan virus were detected by immunofluoroscent antibody technique and RT-PCR. The results are as follows. 1. Five species of Acarina were identified from E. serotinus: Leptotrobidium subakamushi of Trombiculidae, Macronyssus coreanus, Steatonyssuss spinosuss and Steatonychus superans of Macronyssidae, Argas vespertilionis of Metastigmata. 2. Ischnopsyllus needhami of Siphonaptera and Cimex of Hemiptera were identified from E. serotinus. 3. Cycteribia uenoi and Brachytarsina kanoi of Diptera were identified from R. ferrumequinum. 4. The positive rate of rickettsial antibodies in E. serotinus were 17.58%, 15.15%, 22.22%, 52.73% against R. tsutsugamushi, R. typhi, R. sibirica and R. thai tick typhus, respectively. The high positive rate of antibody related to the high content of Arthropoda. 5. The Positive rate of hantaan virus IFA antibodies were 3.4% (27 of 802) and hanntan virus infection rate 36.7% (22 of 60) by RT-PCR in bats. According these result, we showed that certain species of Athropoda isolated playa role as vector of Rickettsia in E. serotinus. Also bats playa role as a reservoir of hantaan virus in nature.

• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.161-166
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• 2019

This study was done to characterize distribution of Rickettsia spp. in ticks in the northwestern and southwestern provinces in the Republic of Korea. A total of 2,814 ticks were collected between May and September 2009. After pooling, 284 tick DNA samples were screened for a gene of Rickettsia-specific 17-kDa protein using nested PCR (nPCR), and produced 88 nPCR positive samples. Of these positives, 75% contained 190-kDa outer membrane protein gene (ompA), 50% 120-kDa outer membrane protein gene (ompB), and 64.7% gene D (sca4). The nPCR products of ompA, ompB, and sca4 genes revealed close relatedness to Rickettsia japonica, R. heilongjiangensis, and R. monacensis. Most Rickettsia species were detected in Haemaphysalis longicornis. This tick was found a dominant vector of rickettsiae in the study regions in the Republic of Korea.

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.235-244
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• 1996

We selected the adequate cell line to be used for propagation and plaquing of R. tsutsugamushi in laboratory and identified R. tsutsugamushi serotype cultured in LuMA cells by nested PCR. As in this study, we concluded that. 1. LuMA cell was suitable for the study of the biology of rickettsiae-host cell interaction. 2. The plaque-forming unit (PFU) per ml of R. tsutsugamushi Karp strain propagated in embryonated egg yolk sacs was $10^{8.8}$ and the PFU/ml of Gilliam strain was $10^{7.1}$. 3. The rate and extent of cytopathic changes depended on the PFU titer of R. tsutsugamushi. 4. PCR with nested primer pairs was useful for identification of R. tsutsugamushi serotype cultured in human embryonic lung cells.

• Korean Journal of Veterinary Research
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• v.35 no.4
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• pp.759-767
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• 1995

One hundred twelve domestic dog sera were collected from Kyonggi, Kanngwon, Cholla, and Kyongsang province. All the sera were examined by immunofluorescence antibody test(IFAT) against scrub typhus, murine typhus and spotted fever group rickettsia infection. The antibody prevalence was 5.40%(6/112) against scrub typhus. The sero-prevalence rates of scrub typhus were 16.30%(5/31) in Cholla and 5.90%(1/17)in Kyonggi areas. The prevalence of scrub typhus was higher in older dogs that were 6 years or more. The antibody prevalence was 8.04%(9/112) against murine typhus. The sero-positive rates to murine typhus were 5.88%(1/17) in Kyonggi, 8.33%(2/24) in Kangwon, 9.68%(3/31) in Cholla, and 7.50%(3/40) in Kyongsang areas, respectively. The sero-positive dogs to murine typhus were widely distributed throughout all age groups from 2 months to above 9 years old. The antibody prevalence was 16.96%(19/112) for spotted fever group rickettsial infection. The sero-positive rates of spotted fever group rickettsia were 11.76%(2/17) in Kyonggi, 12.90%(4/31) in Cholla, and 32.50%(13/40) in Kyongsang areas. The sero-positive dogs to spotted fever group rickettsia were observed at all age groups of dog. The sero-positive prevalence between sex showed higher in female than in male except for spotted fever group rickettsia infection.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.52-57
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• 2020

Bacterial symbionts are common across insects, including ants (Hymenoptera: Formicidae). Reproduction-manipulating endosymbionts, such as Wolbachia, Spiroplasma, Rickettsia, and Cardinium, are closely associated with many aspects of host-insect life. In addition, phage WO plays an essential role in the phenotypic effects of Wolbachia. Although endosymbionts are possible biological control agents, there is a lack of knowledge of their rate of infection of ants in Korea. We tested a range of Korean ant species for the presence of Wolbachia, Spiroplasma, Rickettsia, Cardinium, and phage WO by extracting DNA from the ants and using specific primer sets to test the status of infections. In addition, the mitochondrial cytochrome c oxidase I (COI) gene of the host ants was amplified to confirm the molecular identification and phylogenetic relationship between the hosts. We found that infection with Wolbachia (29.6% of species) is relatively common when compared with that of other endosymbionts. Only one species was infected with Spiroplasma. Infection with Rickettsia and Cardinium was not detected in the examined ants. Most Wolbachia in ants were infected with phage WO. Although the phenotypic effects of endosymbionts in ants are still unknown, this first survey of endosymbionts in Korea is the first step toward the use of reproduction-manipulating endosymbionts.

• Parasites, Hosts and Diseases
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• v.29 no.1
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• pp.87-92
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• 1991

In order to determine the vector species of tsutsugamushi disease in Korea chiggers were individually dissected, and internal contents were tested for Rickettsia tsutsugamushi organisms by means of indirect FA test, and each exoskeleton was mounted on slide for identification. Among 4,142 chiggers collected from 48 Apodemus agrarius at nine different localities during the period of July-November, 1989, 990 chiggers of 10 species of Trombiculidae were dissected and tested. Rickettsiae were confirmed in two Leptotrembidium pallidum larvae out of 447 tested, giving 0.4% of the infection rate. The chiggers of the other species tested were found negative.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.352.1-352
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• 1995