• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.399-405
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• 2016

Poor subsistence farmers who live in a semi-arid area of northern Ethiopia build irrigation systems to overcome water shortages. However, there is a high risk of malaria transmission when increased standing water provides more favorable habitats for mosquito breeding. This is a serious problem because there are many barriers to malaria control measures and health care systems in the area. Using a causal loop diagram and computer simulations, the author attempted to visually illustrate positive and negative feedbacks between mosquito and human populations in the context of Simret, which is a small village located in northern Ethiopia and is generally considered a malaria-free area. The simulation results show that the number of infectious mosquitos increases to 17,215 at its peak, accounting for 3.5% of potentially dangerous mosquitos. At the same time, the number of sick people increases to 574 at its peak, accounting for 15% of local population. The malaria outbreak is controlled largely because of a fixed number of vulnerable people or local population that acts as an intermediate host.

• Korean Journal of Environmental Agriculture
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• v.30 no.1
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• pp.76-81
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• 2011

BACKGROUND: Acorus gramineus is of medicinal plants that exhibit variable biological activities for human health and against insect pests. The extracts of A. gramineus was examined in an attempt to develop a natural repellent against human disease-mediating Culex pipiens. METHODS AND RESULTS: The roots of A. gramineus dried under dark conditions were homogenized and extracted with ethanol. The extracts were subjected to repellent activity assays against C. pipiens in a hand-made acrylamide box with three accessible rooms. Significantly low number of mosquitos was found in the room previously fumigated with the extracts at 50 mg/L on the filter paper, exhibiting less than 20% of mosquitos tested. More than 50% of mosquitos tested was found in the room without the extracts, but less than 30% was found in the room that released mosquitos. GC/MS analysis detected ${\beta}$-asarone as a main component of the extracts. The commercial asarones (${\alpha}$ and ${\beta}$) showed a repellent activity at 50 mg/L on the filter paper similar to the extracts. CONCLUSION(S): A. gramineus has potential for use as a mosquito repellent since ${\beta}$-asarone, a main component of the plant, exhibited a strong repellent activity against C. pipiens.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.189-196
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• 2020

Mosquitos serve as vectors for diseases, causing inconvenience as well as a threat to human life and health. Concern about mosquitos introducing and spreading new diseases has been intensifying. We observed a variety of mosquito habitats based on land cover classification from Korea's Ministry of Environment, and the mosquito species that could appear were classified according to the each habitat type. Finally, we suggested the best control methods for each type of habitat considering habitat characteristics and the ecological traits of mosquitos. Urban areas harbor various habitats for pests, contributing significantly to mosquito habitats. Control must be performed regarding larva and adults because various sources for habitats exist. Public mosquito control programs such as educational training, as well as information brochures can be effective in managing mosquito populations and public health. Agricultural areas show high densities of mosquito larva to lentic zones such as reservoirs, wetlands, paddy fields. So, biological control using natural predators may be effective in controlling mosquito populations. Forests are major habitats for Aedes albopctus, so physical controls should be deployed for residents living nearby, and excessive deforestation should be minimized. Other areas including aquatic ecosystems should be adopted regarding biological control using Bti (Bacillus thuringiensis var. israelensis) and chemical control for eradicating mosquitos. We classified habitats into four types of land cover patterns considering ecological traits and habitat preference, and suggest adequate control methods for each habitat type. Our suggestion can be used to positively contribute toward effective managing mosquito's density and reducing the damage to public health.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.6
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• pp.155-159
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• 2002

This paper describes the development process of mosquito trap with the effect of air cleaning by using the substance-field analysis and evolution pattern of systems in the theory of inventive problem solving (TRIZ). We g(It the concept of the mosquito trap with mosquito attractants instead of mosquito reluctants such as mosquito stick coil and skin medicine with bad and toxic smell. The number of mosquitos traped by one trap near cattle shed per one night in summer, was over 10 thousands with some effects of air cleaning

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.556-559
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• 1997

This paper describes the development process of mosquito trap with the effect of air cleaning by using the substance-field analysis and evolution pattern of systems in the theory of inventive problem solving (TRIZ). By the concept of standard solution about introducing S3 substance, modification of S1 (human) and S2 (mosquito) between first substance SI and second substance S2 with harmful effect, we got the concept of the mosquito trap with mosquito attractants instead of mosquito reluctants such as mosquito stick coil and skin medicine w~th bad and toxic smell. The number of mosquitos traped by one trap near cattle shed per one n~ght in summer, was over 10 thousands with some effects of air cleaning.

• Journal of Veterinary Science
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• v.24 no.2
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• pp.18.1-18.7
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• 2023

Tibet orbivirus (TIBOV) was identified as a novel orbivirus in 2014. Antibodies against TIBOV were detected in cattle, Asian buffalo, and goats, while all the sequenced TIBOV strains were isolated from mosquitos and Culicoides. The known TIBOV strains have been classified into four putative serotypes. In this study, two TIBOV strains isolated from Culicoides spp. in Shizong County of Yunnan Province, China, were fully sequenced. The phylogenetic analysis of outer capsid protein 2 (VP2) indicated that these two viral strains belong to two novel putative serotypes of TIBOV. The updated putative serotypes may help in an investigation of the distribution and virulence of TIBOV.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.177-183
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• 2018

This study examined the seasonal, regional distribution of mosquito vectors related with disease vectors in the Jeju. From March to November, sample were collected from 11 points in four environmentally different sites in Jeju Island. Samples were collected twice a month using a black-light trap and a BG sentinel trap. Overall, five genera and seven species types of 6,042 female mosquitos were collected. Among the collected mosquitos, 4,159 (68.8%) and 1,348 (24.4%) were Culex pipiens and Aedes albopictus, respectively, making them the dominant species. Additionally, collection using the black light trap produced 72.8 entities per trap in Jungang-dong service center in the center of the city, which was the highest value, while the lowest amount of 1.4 per trap was recovered from the airport. When the BG sentinel trap was used, the largest recovery was observed in the port, where there were 71.7 entities per trap, while the lowest amount of 28.3 entities per trap was recovered at Gealmae Eco Park. The overall number of mosquitoes collected started to increase from May, and reached the largest value of 1,156 (19.1%) in August. Trapped mosquitoes are created 364 pools of up to 50 grains per pool, by season, by environmental, and by species. When the pools were used, no flaviviral infection was observed upon real time RT-PCR.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.509-514
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• 2004

Six new serovarieties of B. thuringiensis carrying specific H-antigen have minor differences in biochemical characteristics and morphological characteristics of crystals, which are commonly resistant against four antibiotics. The B. thuringiensis serovar. coreanensis is nontoxic to silkworm larvae, but it is moderately toxic against the Culex pipiens larvae. The B. thuringiensis serovar. konkukian and leesis are nontoxic against mosquitos larvae, but are toxic against silkworm larvae. The B. thuringiensis serovar. seoulensis, sooncheon, and yosoo are highly toxic to B. mori larvae and moderately toxic to C. pipiens larvae. The six serovarieties harbor different plasmid DNA patterns. A 102-kDa protein is a major crystal protein in the four serovarieties and a 86-kDa protein is in one serovariety.

• Parasites, Hosts and Diseases
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• v.39 no.4
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• pp.293-299
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• 2001

The characteristics of vivax malaria epidemics along the demilitarized Bone (DMZ) in the Republic of Korea has been established by the early surveillance data. To further characterize the epidemic, data of civilian patients microscopically diagnosed with malaria from 1995 through 2000 were analyzed in Yonchon-gun (county) . Malaria incidence was greater in male civilians > 30 years of age (p < 0.05). The annual parasite index was significantly higher in those living in the administrative areas (Myeon) traversed by DMZ than those living in Myons not traversed by DMZ (p < 0.05). Analysis according to the distance (4 to 14 km) from DMZ showed that people living in villages close to DMZ had higher annual parasite indices than those living in villages remote from DMZ (p for trend < 0.05). Civilians living in Myeons with plains and located in northwestern part of the county had higher annual parasite indices than those living in hilly Myeons located in southeastern part of the county (p for trend f 0.05). These findings suggest that the contraction of vivax malaria is related with night-time outdoor activities, and that the distance from DMZ is a risk factor. In this area, the flying distance of infected vector mosquitos can explain the annually repeating occurrence of civilian cases.

• Journal of Preventive Medicine and Public Health
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• v.20 no.1 s.21
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• pp.137-146
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• 1987

The following facts have been identified as a result of epidemiological trend and characteristic of Japanese Encephalitis in Korea for the last 20 years. First: The Epidemiological period which was ten-year and three-year in the past has been disappeared following the start of immunization program at 1970. Second: The Incidence rate was much higher in the south and West areas than northeast area of Korea. City and Province with the highest incidence rate was Chungcheong Nam Province and Cholla Buk Province. Third: Regardless of scope of prevalence, the main season that 90 percent of total incidence occurrs in one month from mid-August through mid-September. Fourth: The number of case by age was that 80 percent of total patients is children aged $3{\sim}15$. Recently there is an increase in the number of patients who are elderly people. Fifth: The study on the ecological conditions of mosquito including wintering and effectiveness of immunization for Japanese Encephalitis and duration on antibody should be done. Sixth: There has been no case of Japanese Encephalitis for the last three years since 1984 mainly due to disinfecting to eradicate mosquitos, immunization for vulnerable group of people aged $3{\sim}15$, individual precaution not to be bitten by mosquito, improvement of environment sanitation. While there has been no case of Japanese Encephalitis during last three years, there is possibility that Japanese Encephalitis becomes prevalent again anytime since its virus has been isolated continuously from the natural reservoirs.