• Journal of Ecology and Environment
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• 제41권3호
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• pp.107-113
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• 2017

Background: As the habitat changes in Korea due to climate change, the emergence of disease-mediated vectors is increasing rapidly. Thus for the surveillance of mosquito- and chigger mite-borne disease, their seasonal prevalence and species composition were investigated at seven locations in Daegu, Gunwi and Sangju. Methods: Mosquitoes were collected twice every month from five collection sites using a black light and BG sentinel traps in Daegu and Gunwi from April through November. Chigger mites were investigated twice per month from wild rodents caught with Sherman live traps in Gunwi and Sangju from April through May and September through November. Results: A total of 2,361 female mosquitoes were collected. Cowshed (626 individuals, Trap index (TI) 44.7) and Kyungpook National University campus (846 individuals, TI 60.4) in Daegu had the highest number of mosquitoes in the black light and BG sentinel trap, respectively. The mosquitoes were collected more by BG sentinel trap than the black light trap. Nine mosquito species were trapped, and the Culex pipiens complex was the most commonly mosquito (1,397 individuals, 59.2%), followed by Anopheles sinensis (554 individuals, 23.5%). Anopheles sinensis (531 individuals, 51.9%) and Culex pipiens complex (1,142 individuals, 85.4%) were the most mosquitoes from black light and BG sentinel trap, respectively. In terms of seasonal prevalence, the highest abundance was in July, with 824 individuals collected. In chigger mites, eighty-one wild rodents of five species that are hosts of chigger mites were collected; among them, 53 and 25 individuals of Apodemus agrarius and Crocidura suaveolens, respectively were trapped. Leptotrombidium pallidum was a dominant species, with 2,467 individuals collected (67.8%). Conclusions: The mosquito was the dominant species in Culex pipiens complex and the highest in July and August. Apodemus agrarius was most abundant in wild rats and Leptotrombidium pallidum was dominant in the collected chigger mites.

• Parasites, Hosts and Diseases
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• 제61권3호
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• pp.272-281
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• 2023

Chigger mites are the vector of scrub typhus. This study estimates the infestation status and ecological characteristics of chiggers on the chestnut white-bellied rat Niviventer fulvescens in Southwest China between 2001 and 2019. Chiggers were identified under the microscope, and infestation indices were calculated. The Preston's log-normal model was used to fit the curve of species abundance distribution. A total of 6,557 chiggers were collected in 136 of 342 N. fulvescens rats, showing high overall infestation indices (prevalence=39.8%, mean abundance=19.2, mean intensity=48.2) and high species diversity (S=100, H'=3.0). Leptotrombidium cangjiangense, Neotrombicula japonica, and Ascoschoengastia sifanga were the three dominant chigger species (constituent ratio=42.9%; 2,736/6,384) and exhibited an aggregated distribution among different rat individuals. We identified 100 chigger species, with 3 of them (Leptotrombidium scutellare, Leptotrombidium wenense, and Leptotrombidium deliense) as the main vectors of scrub typhus in China and nine species as potential vectors of this disease. Disease vector occurrence on N. fulvescens may increase the risk of spreading scrub typhus from rats to humans. Chigger infestation on N. fulvescens varied significantly in different environments. The species abundance distribution showed a log-normal distribution pattern. The estimated number of chigger species on N. fulvescens was 126 species.

• Parasites, Hosts and Diseases
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• 제27권2호
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• pp.141-144
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• 1989

1987년 10월부터 12월에 걸쳐 경기도 포천군 이개 부락과 경상남도 진해시 일개 부락에 서 채집한 등줄쥐(Apedemus agrariuscoreae)의 이개에 기생한 털진드기유를 조사하여 다음과 같은 결과를 얻었다. 채집된 171필의 등줄쥐 중 58필에서 털진드기가 잡혀 기생률은 33.9%이었다. 그 중 한 종만 발견된 숙주가 27필(46.6%)로 가장 많았고, 기생 종수가 많아질수록 감소하였으며 5종이 기생하는 쥐는 2필(3.4%)뿐이었다. 총 865개체의 털진드기 유충을 동정한 결과 Leptotrombidium Pallidum (4.3%), L. palpate(23.0%), L. orientalis(20.2%), L. wetum(19.0%), Neotrombicula tamiyai (32.9%), N. japonica(0.2%) 및 Euschongastia koreaensis(0.3%)의 7종이 확인되었다. 그 중 N. tamiyai가 285개체(32.9%)로 가장 많았으나 이 종은 일개 지역에서 12월에만 집중 채집되었으므로 우리 나라 우점종은 전 조사지역과 기간에 고루 분포되어 있는 것으로 나타난 L. palpale라 추측된다. 쭈쭈가무시병의 매개종인 L. pallidum은 37개체가 채집되어 전체의 4.3%에 불과하였다. 한 숙주에 기생하는 털진드기의 밀도는 1개체로부터 최고 207개체까지 심한 차이를 보였는데 개체마다 한 두 종이 집중 기생하는 경향을 나타내었다.

• 한국동물학회지
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• 제2권1호
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• pp.17-28
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• 1959

In Korea ,little attention was paid to chiggers until 1950 so only to reports on four species of chiggers were pulished before Korean War. Since 1950 (beginning of Korean War), a marked progress in the study of chiggers has been made in connection with investigations of Epidemic hemorrhagic fever occurring among the United Nations troops which was suspected as a chigger-borne infectious disease and the first report of tsutsugamushi disease in Korea called natives attention to chiggers as the vector mites of this newly known disease in Korea. This paper is mostly based on specimens of author's collections from 3269 Rodentia Insectivora, 9 Chiroptera, 24 Aves , 35 Amphibia and 3 Reptilia during the time from December 1955 to December 1956 but four species were introduced here from works of others . There are reported here five species of chiggers previously known only out of Korea and a new species also. This new species was collected by author but Lipovsky informed his colleague had collected the same one in Korea and they would publish it as new one in near future. This is the reason of describing the new species without specific name . Of course, this paper is incomplete in view of the geographic distribution, seosonal change and host relation etc, but will serve as a brief summary of the chiggers fauna of Korea up to the present. This species described here are as follows : Gahrliepia brennani var. ventralis Neoschongastia posekanyi Euschongastia kigtajimai Euschongastia miyagawai Euschongastia koreaensis Trombicula nagayoi Trombicula japonica Trombicula pomeranzevi Trombicula mitamurai Trombicula tamiyai Trombicula palpalis Trombicula orientalis Trombicula pallida Trombicula scutellaris Trobmicula miotis Trombicula hiranumai Trombicula sp. Trombicula hiranumai Trombicula sp. Trombicula subintermedius Shunsennia tarsalis . Euschongastia ikaoensis . Trombicula koomori Trombicul subakanushi

• Parasites, Hosts and Diseases
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• 제59권1호
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• pp.1-8
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• 2021

Leptotrombidium scutellare is one of the 6 main vectors of scrub typhus in China. It has been found in more than 15 provinces of China. Especially in Yunnan, it was found to be mainly distributed in some mountainous areas with high altitude, low temperature and low precipitation. Rodents and some other small mammals were the most common hosts of L. scutellare. To date, more than 40 host species of L. scutellare have been recorded with very low host specificity, and the main hosts varied in different geographical regions. L. scutellare had a strong resistance against the cold environment, and the temperature and humidity were 2 important factors affecting its growth and development. Among different individuals of their rodent hosts, L. scutellare mites often showed an aggregated distribution pattern, which reflected the interspecific cooperation of the mites. The chromosome karyotype of L. scutellare was 2n=16 and all the 8 pairs of chromosomes were short rod-shaped with metacentric or sub-metacentric types. The isozyme spectrum supported that L. scutellare, L. deliense and L. rubellum were in the same species group. Based on the natural infection, experimental transmission and epidemiological evidence, L. scutellare has been eventually confirmed as the second major vector of scrub typhus in China, which is second only to L. deliense.

• Tuberculosis and Respiratory Diseases
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• 제61권4호
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• pp.389-393
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• 2006

저자들은 홍반성 구진양 발진으로 발현된 쯔쯔가무시병환자에서 단순 피부질환으로 간과하여 치료의 시기가 지연되고 스테로이드 등의 약물 사용으로 급성 신부전 및 급성 호흡부전으로 진행된 1례를 경험 하였기에 문헌 고찰과 함께 보고하는 바이다.