• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.63-67
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• 2014

This paper describes a new species of chigger mite (Acari: Trombiculidae), Gahrliepia cangshanensis n. sp., from rodents in southwest China. The specimens were collected from Yunnan red-backed voles, Eothenomys miletus (Thomas, 1914), and a Chinese white-bellied rat, Niviventer confucianus (Milne-Edwards, 1871) in Yunnan Province. The new species is unique mainly in its number of dorsal setae (n=21), and it has the following features: fT (formula of palpotarsus)=4B (B=branched), fp (formula of palpal seta)=B/N/N/N/B (N=naked), a broad tongue-shaped scutum with an almost straight posterior margin, and 17 PPLs (posterior posterolateral seta) with a length of 36-43 ${\mu}m$. This chigger mite may also infect other rodent hosts and may be distributed in other localities.

• The Korean Journal of Soil Zoology
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• v.11 no.1_2
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• pp.16-19
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• 2006

A checklist on 61 species of chigger mites belonging to 12 genera and 2 families from Korean peninsula is suggested with Korean names of each taxon.

• 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.

• The Korean Journal of Zoology
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• v.36 no.3
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• pp.408-415
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• 1993

Studies on seasonal prevalence and geographical distribution of chigger mites were carried out during the period of August 1990-December 1991, and the results are summarized as follows. From total 325 field rodents collected during the study period, 15,679 chiggers were obtained and 12 species of 4 genera were identified. Leptotrombidium pallidum, a vector species of tsutsugamushi disease in Korea was the predominant species and distributed throughout the country except southern part of Korea, whereas L. scutellare, known also as a vector species was distributed mainly in southern part of Korea. The distribution of chigger mites was strongly localized by species, showing different predominant species at each locality during the same season. The predominant species were L. pallidum(92.3%) at Dorai-5ri, Wondang-ub, Neotrombicula kwangneungensis (44.7%) at Sanjung-ri, Pochun-gun, N. tamiyai (55.1%) at Changgok-ri, Paju-gun, L. orientale (55.2%) at Jangsin-ri, Iksan-gun, and L. scutellare (47.6%) at Sinyong-dong, Iri-si. Study on seasonal prevalence of L. pallidum chiggers resulted that they started appearing in September, showed the peak in November, almost disappeared during the period of December-March, reappeared in April-May showing a small peak, and again almost disappeared until September. L. scutellare showed the peak in October, sharply decreased thereafter, and disappeared during the period of January-September.

• Parasites, Hosts and Diseases
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• v.30 no.4
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• pp.341-348
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• 1992

Because no reference on trombiculid mites (Acarina: Trombiculidae) in Cheju Island where tsutsugamushi disease is highly endemic had been available, studies on trombiculid mites in Cheju Island were implemented during the period of August 1991-Apil 1992, and the results obtained are summarized as follows: (1) The species and numbers of the field rodents collected were 143 Apodemus agrarius chejuensis (92.3%), 11 Crocidura lasiura (7. l%) and 1 Micromys minutus (0.6%) From total 12,075 chiggers harvested, 9 species of 4 genera in Trombiculidae were identified. (2) The predominant species through all seasons was 1. setum (43.3%), followed by 1. orientale (27.4%) and 1. scutellare (26.6%). However, in autumn when the most cases of tsutsugamushi disease occur, 1. scutellere was prominently predominant, having 79.8% of the collected chiggers. (3) Among 1,1421. scutellare examined for Rickettsia tsutsugpmushi by means of IFA test, 6 individuals were found positive showing 0.5% of infection rate. This is the first finding that 1. scutellere is the second vector species of tsutsugamushi disease in Korea. (4) Antibody positive rate of A. agrarius chejuensis sera were 31.2% (44/139), and 1 M. minutes serum was also found positive. The seropositive rates by season were not so significantly different. Key words: Tsutsugamushi disease, epidemiology, vector species, Cheju Island, Korea.

• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.141-144
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• 1989

During October-December 1987, chigger mites infested on the striped field mice (Apodemus agrarius cereae) collected at Pochun-gun, Gyeonggi Province and Chinhae city, Kyongnam Province were identified. . 1. Of 171 back-striped mice collected, chigger mites wire found from 58 mice, showing 33.9% of infestation rate. 2. Total 865 chigger mites collected were classified into seven species; Leptotrombidium pallidum (4.3%), L. palpate(23.0%), L. orienpalis(20.2%), L. xetum(19.0%), Neotrombicula tamiyai(32.9%), JV. japonica(0.25%) and Euschongastia koreaensis(0.3%). Though the most dominant species in number was N. tamiyai(32.9% of the total), this species was collected at very limited locality and for a short period. Therefore, most common species in Korea seems to be L. palpale which was found at all localities throughout the whole survey period. L. pallidum which is known as the vector species of tsutsugamushi disease in Korea was collected in a very low number(4.3% of the total chiggers collected). 3. The number of chigger mites infested on a host animal showed great variations from one chigger up to 207 chiggers. The present study has shown that there may be other Leptotrombidium species mite(s) for the vector and host of tsutsugamushi disease in Korea.

• Animal Systematics, Evolution and Diversity
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• v.6 no.1
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• pp.57-70
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• 1990

한국산 털진드기 종을 다룬 모든 문헌을 조사 정리한 결과 총 43종이 보고되었는데, 그중 Salchia brennani ventralis 는 오동정한 것으로 W. comataxila 이었고 Shunsennia gracilis 는 S. hertigi 의 동종이명일 가능성이있으나 문헌상으로는 확인할 수 없었다. Leptotromibidium intermedium 의 경우 문헌상의 근거가 전혀 없어 국내 서식종으로 인정할 수 없었다. 필자가 직접 표본을 조사하여 확인할 수 있었던 종은 모두 17 종이었는데 그 가운데 Leptotromibidium akamushi 는 L.zutum 의 , L.miyajimai 는 L.orientale 의 오동정이었다. 결국 한국산 털진드기류는 모두 2과 , 12속, 39종이 된다. 이 중 2 종은 조류에 , 7종은 박쥐에, 그리고 29종은 설치류에 각각 기생하는 종이고 1종은 조류와 포유류에 공동기생하는 종이다. 현재 한국산 털진드기를 동정하는데 이용할 수 있는 검색표로는 29종을 아룬 Southwick (1968) 의것이 있을 뿐이고, 우리나라와 동물상이 유사하나 일본 종에 대한 검색표도 우리나라 토착종 21종이 들어 있지 않아 도움이 되지 않는다. 뿐만 아니라, 기존 검색표는 다리의 강모식(leg setal formula) 이나 촉수의 강모식( palpal setal formula)등 관찰하기 어려운 형질을 많이 사용하고 있어서 동정에 어려움이 많았다. 이에 필자는 현재까지 한국 종으로 정리된 총 39종에 대한 검색표를 만들었는데, 관찰이 용이하면서도 변이가 적은 형질을 최대한 사용하였고 특히 종 특징을 잘 나타내는 배판(scutum)의 형질을 주로 사용하였다. 실용성이 보다 큰 도식형 검색표( pictorial key)도 함께 만들었는데 원저자들의 도표에서 배판(scutum)을 그대로 전사하여 종 간 비교를 용이하게 하였다.

• 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.55 no.5
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• pp.555-559
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• 2017

Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China ($114-112^{\circ}E$, $34-38^{\circ}N$), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China.