• Parasites, Hosts and Diseases
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• 제53권1호
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• pp.135-139
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• 2015

A total of 1,708 small mammals (1,617 rodents and 91 soricomorphs), including Apodemus agrarius (n = 1,400), Microtus fortis (167), Crocidura lasiura (91), Mus musculus (32), Myodes (= Eothenomys) regulus (9), Micromys minutus (6), and Tscherskia (= Cricetulus) triton (3), were live-trapped at US/Republic of Korea (ROK) military training sites near the demilitarized zone (DMZ) of Paju, Pocheon, and Yeoncheon, Gyeonggi Province from December 2004 to December 2009. Small mammals were examined for their intestinal nematodes by necropsy. A total of 1,617 rodents (100%) and 91 (100%) soricomorphs were infected with at least 1 nematode species, including Nippostrongylus brasiliensis, Heligmosomoides polygyrus, Syphacia obvelata, Heterakis spumosa, Protospirura muris, Capillaria spp., Trichuris muris, Rictularia affinis, and an unidentified species. N. brasiliensis was the most common species infecting small mammals (1,060; 62.1%) followed by H. polygyrus (617; 36.1%), S. obvelata (370; 21.7%), H. spumosa (314; 18.4%), P. muris (123; 7.2%), and Capillaria spp. (59; 3.5%). Low infection rates (0.1-0.8%) were observed for T. muris, R. affinis, and an unidentified species. The number of recovered worms was highest for N. brasiliensis (21,623 worms; mean 20.4 worms/infected specimen) followed by S. obvelata (9,235; 25.0 worms), H. polygyrus (4,122; 6.7 worms), and H. spumosa (1,160; 3.7 worms). A. agrarius demonstrated the highest prevalence for N. brasiliensis (70.9%), followed by M. minutus (50.0%), T. triton (33.3%), M. fortis (28.1%), M. musculus (15.6%), C. lasiura (13.2%), and M. regulus (0%). This is the first report of nematode infections in small mammals captured near the DMZ in ROK.

• Parasites, Hosts and Diseases
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• 제30권4호
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• pp.341-348
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• 1992

1991년 8원부터 1992년 4월에 걸쳐, 쭈쭈가무시병 환자 다발생 지역의 하나인 제주도에서 털진드기류에 관한 연구를 실시하여 다음과 같은 결과를 얻었다. (1) 채집된 들쥐 155마리 중 등줄쥐 (Apedemus agrarirsschejuensis) 가 143마리 (92.3%)로 우점종이었고, 땃쥐 (Crocidura laciura) 11마리 (7.1%)와 멧밭쥐 (Micromys minutus) 1마리 (0.6%)였다. 이들 들쥐에 기생한 12,075개체의 털진드기를 동정한 결과 4속 9종이 확인되었다. 그 중, 사 계절을 통한 우점종은 L. zetum(43.3%)이었다. (2) 털진드기 개체군의 계절별 밀도를 비교하면 교. tetu변은 겨 울(46.2%)과 봄(42.9%)에 주로 출현하였고, L. orientale는 겨울(57.7%)에 피크를 보였다. L. scutellare는 가을에 96.0%로 집중적인 발생을 보였고, 가을에 출현하는 모든 털진드기의 79.8%를 차지하여 가을의 우점종으로 쭈쭈가무시병 환자 발생시기와 일치하였다. (3) 총 1,476 개체의 털진드기 유충을 해부하여 그 내용물을 간 접면역형광현미경법으로 관찰한 결과 1,142 개체의 L. scutellare 중 6 마리가 항원 양성으로 확인되어 (감염률 0.5%), 우리 나라에서는 처음으로 L. scutellare도 매 개종임이 밝혀졌다. (4) 채집된 139마리의 등줄쥐 가운데 44마리가 R. tsutsugamushi에 대한 함체 양성으로 나타나 양성률은 31.2%이었다. 사계절을 통한 양성률의 큰 차이는 보이지 않았다.

• 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.

• 환경생물
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• 제21권3호
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• pp.257-261
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• 2003

소형포유류는 생태계의 생체내 중금속축적에 대한 지표종으로 많이 활용되고 있다. 본 연구는 금호강에 서식하는 소형포유류의 생물축적에 대한 연구를 위해 2002년 5월 28일~6월 12일에 걸쳐 포획을 실시하였다. 포획을 위해 셔만트랩과 스냅트랩이 사용되었으며 등줄쥐와 우수리땃쥐 등 2종 총 39마리를 포획하였다. 그 중 동정이 가능한 30마리에 대한 중금속조사를 실시하였으며 개체군 중 16마리(53.3%)가 번식기에 접어든 것으로 나타났다. 중금속 4가지(Cu, Pb, Zn, Cd)에 대하여 분석이 실시되었으며 그 중 등줄쥐의 Zn은 신장(6.83mg $kg^{-1}$)이 간(3.66mg $kg^{-1}$)보다 높은 축적을 나타내었다. 하지만 Cu의 축적은 간이 신장보다 높게 나타났다. 이 지역이 대구시 달서구의 염색공단에서 비교적 거리가 있는 지역임에도 불구하고 Cu, Zn의 축적은 금호강변에 높은 것으로 조사되었다. 본 연구는 우리나라 소형포유류에 대한 최초의 정량적인 연구이며 향후 중금속 오염이 진행되는 산업단지에 본 조사의 연구결과가 기초자료로 활용될 수 있다.

• Parasites, Hosts and Diseases
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• 제50권4호
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• pp.327-331
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• 2012

Monthly surveys were conducted to investigate the occurrence of chigger mites and seroprevalence of scrub typhus among small mammals in Jeollanam-do, the southwestern part of Korea, from November 2006 through October 2007. Fifty-eight small mammals, including 57 Apodemus agrarius (98.3%) and 1 Crocidura lasiura (1.7%), were captured, and a total of 4,675 chigger mites representing 4 genera and 8 species were collected from them. The chigger infestation rate among small mammals was 69.0%. The most predominant species in A. agrarius was Leptotrombidium scutellare (54.0%), followed by Leptotrombidium pallidum (39.4%), Leptotrombidium orientale (4.4%), Leptotrombidium palpale (1.1%), Neotrombicula tamiyai (0.6%), Eushoengastia koreaensis (0.3%), Neotrombicula gardellai (0.3%), and Cheladonta ikaoensis (<0.1%). The chigger index of A. agrarius was the highest in October (740.0), followed by November (242.0), September (134.6), March (98.3), February (38.2), January (35.3), December (34.5), April (30.8), and May (1.7). The average antibody positive rate of scrub typhus in wild rodents was 50.0%. The seropositive rates were high in October (100.0%) and November (83.3%), whereas those in other months were relatively low (28.6-57.1%). The chigger index of L. scutellare rapidly increased in September to form an acuminate peak in October, followed by a gradual decline. These results suggest that the outbreak of scrub typhus in the southwestern part of Korean peninsula is mostly due to L. scutellare.

• Parasites, Hosts and Diseases
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• 제54권3호
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• pp.307-313
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• 2016

Serosurveillance for zoonotic diseases in small mammals and detection of chiggers, the vector of Orientia tsutsugamushi, were conducted from September 2014 to August 2015 in Gwangju Metropolitan Area. Apodemus agrarius was the most commonly collected small mammals (158; 91.8%), followed by Myodes regulus (8; 4.6%), and Crocidura lasiura (6; 3.5%). The highest seroprevalence of small mammals for O. tsutsugamushi (41; 26.3%) was followed by hantaviruses (24; 15.4%), Rickettsia spp. (22; 14.1%), and Leptospira (2; 1.3%). A total of 3,194 chiggers were collected from small mammals, and 1,236 of 3,194 chiggers were identified with 7 species of 3 genera: Leptotrombidium scutellare was the most commonly collected species (585; 47.3%), followed by L. orientale (422; 34.1%), Euchoengastia koreaensis (99; 8.0%), L. palpale (58; 4.7%), L. pallidum (36; 2.9%), Neotrombicula gardellai (28; 2.3%), and L. zetum (8; 0.6%). L. scutellare was the predominant species. Three of 1,236 chigger mites were positive for O. tsutsugamushi by PCR. As a result of phylogenetic analysis, the O. tsutsugamushi strain of chigger mites had sequence homology of 90.1-98.2% with Boryong. This study provides baseline data on the distribution of zoonotic diseases and potential vectors for the development of prevention strategies of vector borne diseases in Gwangju metropolitan area.

• Parasites, Hosts and Diseases
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• 제58권3호
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• pp.301-308
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• 2020

Owing to global climate change, the global resurgence of vector-borne infectious diseases and their potential to inflict widespread casualties among human populations has emerged as a pivotal burden on public health systems. Tsutsugamushi disease (scrub typhus) in the Republic of Korea is steadily increasing and was designated as a legal communicable disease in 1994. The disease is a mite-borne acute febrile disease most commonly contracted from October to December. In this study, we tried to determine the prevalence of tsutsugamushi disease transmitted by chigger mites living on rodents and investigated their target vector diversity, abundance, and distribution to enable the mapping of hotspots for this disease in 2015. A total of 5 species belonging to 4 genera (109 mites): Leptotrombidium scutellare 60.6%, L. pallidum 28.4% Neotrombicula tamiyai 9.2%, Euschoengastia koreaensis/0.9%), and Neoschoengastia asakawa 0.9% were collected using chigger mite collecting traps mimicking human skin odor and sticky chigger traps from April to November 2015. Chigger mites causing tsutsugamushi disease in wild rodents were also collected in Hwaseong for the zoonotic surveillance of the vector. A total of 77 rodents belonging to 3 genera: Apodemus agrarius (93.5%), Crocidura lasiura (5.2%), and Micromys minutus (1.3%) were collected in April, October, and November 2015. The most common mite was L. pallidum (46.9%), followed by L. scutellare (18.6%), and L. orientale (18.0%). However, any of the chigger mite pools collected from rodent hosts was tested positive for Orientia tsutsugamushi, the pathogen of tsutsugamushi disease, in this survey.

• Parasites, Hosts and Diseases
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• 제45권2호
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• pp.157-161
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• 2007

A total of 1,496 rodents and insectivores were live-trapped at Yeoncheon-gun (n = 351), Paju-shi (804), and Pocheon-gun (343), Gyeonggi-do (Province), and examined for intestinal helminths, including Neodiplostomum seoulense, seasonally from December 2004 to September 2005. Six species of rodents, including Apodemus agrarius (1,366), Mus musculus (32), Micronytus fortis (28), Eothenomys regulus (9), Micronys minutus (6), and Cricetulus triton (3), and 1 species of insectivores Crocidura lasiura (54) were collected. A total of 321 adult N. seoulense were collected from 19 (1.4%) A. agrarius. The worm burden ranged from 1 to 101 per A. agrarius (mean; 16.9). No N. seoulense was observed in other rodent or insectivore species examined. The infection rate during autumn (4.5%) was higher than those during spring (0.8%), summer (0.8%), and winter (0.5%). The average number of N. seoulense in infected A. agrarius was the highest in spring (66.0 specimens), followed by autumn (15.2), winter (4.5), and summer (3.3). This study first confirms that A. agrarius is a natural definitive host for N. seoulense, and demonstrates that the infection rates and intensities vary seasonally and geographically.