• 대한임상검사과학회지
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• 제52권4호
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• pp.364-371
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• 2020

질병관리본부에서는 매개체로 인한 전파 확산에 대처하고자 전국 권역별 기후변화 매개체 감시사업을 실시하고 있으며 일환으로 전북 진안지역의 쯔쯔가무시 매개체인 털진드기 분포 조사와 병원체 검사를 위해 채집기와 야생설치류 포획을 실시하였다. 털진드기 종 분류를 위해 9~12월 둘째주까지 매주 1회씩, 총 20개의 채집기를 이용하여 채집한 결과 총 개체수는 8종 611마리가 채집되었다. 종 분류 결과는 둥근혀털진드기(N. tamiyai) 434마리(71.0%)로 가장 많이 분리되었다. 야생설치류 포획으로 털진드기 채집은 66마리의 설치류를 포획해서 털진드기 총 3,050마리 채집되어 chigger index는 46.2로 나타났다. 월별 chigger index는 11월 206.1로 가장 높았다. 병원체 보유여부 검사결과 총 85개의 pools중 5월과 9월에 각각 1개의 pools에서 양성을 확인하였다. 이러한 결과는 쯔쯔가무시증 환자가 빈번히 발생하는 봄과 가을철의 시기와도 일치하였다.

• 대한임상검사과학회지
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• 제48권3호
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• pp.242-246
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• 2016

2013년 4월부터 11월까지 전라남도 곡성군 지역을 대상으로 들쥐를 포획하고 기생하는 털진드기의 분포를 조사하였다. 597개의 trap에서 79마리를 포획하여 포획률은 13.2%였고, 종류별로는 등줄쥐가 92.4%를 차지하여 절대 우점종이었다. 79마리의 들쥐중 68마리에 털진드기가 기생하고 있어 86.0%의 기생률을 보였고, 74.5개체의 chigger index를 보였다. 5,063개체의 채집한 털진드기는 2속 6종으로 동정되었고, 활순털진드기가 3,535개체(69.8%)로 절대적인 우점종이었다. 계절별로 봄철에는 대잎털진드기, 가을철에는 활순털진드기가 높은 밀도로 채집되어 진드기종의 분포가 채집시기에 따라 차이가 있었다.

• Parasites, Hosts and Diseases
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• 제55권5호
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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.

• Parasites, Hosts and Diseases
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• 제58권4호
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• pp.445-450
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• 2020

Trombiculid "chigger" mites (Acari) are ectoparasites that feed blood on rodents and another animals. A crosssectional survey was conducted in 7 ecosystems of southern Vietnam from 2015 to 2016. Chigger mites were identified with morphological characteristics and assayed by polymerase chain reaction for detection of rickettsiaceae. Overall chigger infestation among rodents was 23.38%. The chigger index among infested rodents was 19.37 and a mean abundance of 4.61. A total of 2,770 chigger mites were identified belonging to 6 species, 3 genera, and 1 family, and pooled into 141 pools (10-20 chiggers per pool). Two pools (1.4%) of the chiggers were positive for Orientia tsutsugamushi. Ricketsia spp. was not detected in any pools of chiggers. Further studies are needed including a larger number and diverse hosts, and environmental factors to assess scrub typhus.

• 대한임상검사과학회지
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• 제53권4호
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• pp.317-325
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• 2021

털진드기 발생감시를 위해 논, 밭, 수로, 초지 4지점에 채집기를 설치하여 조사하였다. 전체 채집 개체수는 7종 207마리가 채집되었다. 9월 5째주에 2마리를 시작으로 11월 3째주에 49마리로 가장 많이 채집되었다. 전체 채집 기간 중 지역별로는 초지, 수로, 논, 밭에서 각각 81, 52, 47, 27마리 채집된 털진드기를 표본 제작하여 동정한 결과 광릉털진드기(N. kwangneun) 73마리(35.3%)로 가장 많이 분리되었고, 수염털진드기(L. palpale)가 46마리(22.2%), 둥근혀털진드기(N. tamiyai)가 41마리(19.8%), 작은새방울털진드기(N. asakawai) 27마리(13.0%) 순으로 동정되었다. 야생설치류 44마리를 포획한 결과 등줄쥐(Apodemus agrarius) 35마리(79.5%), 땃쥐류(Crocidura spp.) 5마리(11.4%), 대륙밭쥐(Craseomys regulus) 2마리(4.5%)와 그동안 발견되지 않았던 흰넓적다리붉은쥐(Apodemus peninsulae) 2마리(4.5%)였다. 설치류에서 채집한 털진드기는 총 6,628마리 채집되어 chigger index는 150.6이었다. 시기별 chigger index는 10월에 234.2로 가장 높았고, 11월에 223.3, 4월에 75.6, 5월에 66.2 순으로 나타났다. 털진드기 검체로부터 쯔쯔가무시 병원체 PCR 검사는 모두 음성이었다.

• 대한임상검사과학회지
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• 제51권3호
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• pp.344-350
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• 2019

Orientia tsutsugamushi 감시를 위한 털진드기 분포를 제주도 서귀포시 일원에서 조사 하였다. 총 20개의 채집기를 이용하여 논, 밭, 수로, 초지(4개 지점)에서 털진드기 유충을 9~11월까지 매주 1회씩 채집한 결과 개체수는 3종 51마리가 채집되었다. 설치류에 기생하는 털진드기 분포 감시를 2018년 3월부터 11월까지 한달에 한번씩 9개월 동안 논, 수로, 밭, 저수지, 야산(5개 지점)에서 Sherman traps 각 20개씩 100개를 설치해서 채집한 결과 64마리의 들쥐를 포획해서 trap index 0.08 이였다. 포획된 들쥐는 한 종류인 등줄쥐(Apodemus agrarius)로만 확인되었다. 시기별로는 4월에 15마리로 가장 많았고, 포획된 64마리의 야생 설치류에서 털진드기가 436마리 채집되어 chigger index는 6.8이었으며 시기별 chigger index는 11월 46.0로 가장 높았고, 7월에 6.8, 6월에 4.6 순으로 나타났다. 채집기와 포획된 설치류에서 채집한 털진드기 총 487마리에 대한 쯔쯔가무시 보유여부를 확인하기 위해서 PCR을 실시한 결과 모두 음성으로 나타났다.

• Parasites, Hosts and Diseases
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• 제59권5호
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• pp.473-479
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• 2021

A nationwide survey of chigger mites causing scrub typhus and an investigation of epidemiologic factors for chigger mites was conducted at 16 localities in 8 provinces in Korea during autumn 2009, 2012, and 2013. A total of 233 Apodemus agrarius were captured, and all were infested with chigger mites. The chigger index was highest in Chungcheongbuk-do in 2009 (358.3) and 2012 (290.1) and Chungcheongnam-do in 2013 (294.4). The predominant chigger mite species was Leptotrombidium pallidum in the northern and central parts and L. scutellare in the southern and western parts, Korea. L. pallidum was not found in Jellanam-do and Gyeongsangnam-do and the distribution of L. scutellare had been expanded in the northern parts of Korea. The chigger index of L. pallidum was positively correlated with temperature and negatively correlated with humidity. The incidence of scrub typhus is dependent on L. scutellare index. These findings could be helpful to monitor the distribution of chigger mites and to develop a preventive measures for scrub typhus in Korea.

• Parasites, Hosts and Diseases
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• 제59권4호
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• pp.377-392
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• 2021

This paper is to illustrate the infestation and related ecological characteristics of chigger mites on the Asian house rat (Rattus tanezumi). A total of 17,221 chigger mites were collected from 2,761 R. tanezumi rats, and then identified as 131 species and 19 genera in 2 families. Leptotrombidium deliense, the most powerful vector of scrub typhus in China, was the first major dominant species on R. tanezumi. All the dominant mite species were of an aggregated distribution among different individuals of R. tanezumi. The species composition and infestations of chiggers on R. tanezumi varied along different geographical regions, habitats and altitudes. The species-abundance distribution of the chigger mite community was successfully fitted and the theoretical curve equation was ${\hat{S}}(R)={37e^{-(0.28R)}}^2$. The total chigger species on R. tanezumi were estimated to be 199 species or 234 species, and this further suggested that R. tanezumi has a great potential to harbor abundant species of chigger mites. The results of the species-plot relationship indicated that the chig-ger mite community on R. tanezumi in Yunnan was an uneven community with very high heterogeneity. Wide geographi-cal regions with large host samples are recommended in the investigations of chigger mites.

• 한국토양동물학회지
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• 제11권1_2호
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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.

• 대한의생명과학회지
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• 제17권4호
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• pp.367-370
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• 2011

Studies on the relative abundance of potential vectors of scrub typhus was conducted from April to October 2009 at the Jangseong of Jeonnam Province, Korea. Among the total 62 field rodents collected by the Sherman collapsible traps, 56 rodents were $Apodemus$ $agrarius$ (90.3%), 4 were $Crocidura$ $lasiura$ (6.4%) and 2 were $Cricetulus$ $triton$ $nester$ (3.2%). Out of the 62 field rodents, 39 were parasitized by chiggers, showing 62.9% of the infestation rate and 80.0 of the chigger index. Chigger index of $A.$ $agrarius$ and $C.$ $triton$ $nester$ were 79.9, 82.0, respectively. But chigger mite was not collected from $C.$ $lasiura$. From the trapped field rodents, 3,120 chiggers were collected and identified with 6 species of 2 genera. $Leptotrombidium$ $scutellare$, the vector species of tsutsugamushi disease, was the dominant species, showing 2,276 chiggers (72.9%). $L.$ $pallidum$ was the second dominant species showing 346 chiggers (11.0%). The distribution of chigger mites was showed the different dominant species according to seasons. $L.$ $pallidum$ was the predominant chigger collected in April (34.8%), May (77.8%) and Jun (39.3%), whereas $L.$ $scutellare$ was the predominant chigger collected in September (78.78%) and October (76.8%).