• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.645-650
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• 2013

A simple, rapid, and high-throughput method for detection and identification of Wuchereria bancrofti, Brugia malayi, Brugia pahangi, and Dirofilaria immitis in mosquito vectors and blood samples was developed using a real-time PCR combined with high-resolution melting (HRM) analysis. Amplicons of the 4 filarial species were generated from 5S rRNA and spliced leader sequences by the real-time PCR and their melting temperatures were determined by the HRM method. Melting of amplicons from W. bancrofti, B. malayi, D. immitis, and B. pahangi peaked at $81.5{\pm}0.2^{\circ}C$, $79.0{\pm}0.3^{\circ}C$, $76.8{\pm}0.1^{\circ}C$, and $79.9{\pm}0.1^{\circ}C$, respectively. This assay is relatively cheap since it does not require synthesis of hybridization probes. Its sensitivity and specificity were 100%. It is a rapid and technically simple approach, and an important tool for population surveys as well as molecular xenomonitoring of parasites in vectors.

• 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 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.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.600-606
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• 2019

The study site was the camping area in the Hwarang Amusement Park in Danwon-gu, Ansan-si. Study activities were conducted three times a week from July 20, 2018, to August 1, 2018. A control site, natural enemy site, and Bti(Bacillus thuringiensis israelensis) site were selected. The analyses included habitat environment and species composition analyses, community analysis, correlation analysis, and similarity analysis. The water quality analysis found no significant difference in water quality over the study period (p>0.05). A total of 4,818 individuals, 38 species, 22 families, and 11 orders were observed during the study period. The natural enemy site observed during the study period had a similar species composition as the control site. The Bti site differed from other sites by the low number of species and individuals present. According to the community analysis, the natural enemy site was a stable community and the Bti site was an unstable community during the study period. Diptera showed negative associations with temperature and water temperature and mosquito larvae showed significant correlations with temperature and water temperature. The similarity analysis showed that the control site and the natural enemy site were 61.11-73.68% and the Bti site showed 30.77-56.00% similarity.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.331-336
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• 2005

Four mosquito repellents, product A (aerosol), product B (liquid), product C (aerosol) and product D (lotion) were tested for their persistent repellency and quantity of DEET remained with the lapse was analyzed. In shirt term test with human (or 8 hours, product A (aerosol), product B (liquid), product C (aerosol) and product D (lotion) appeared over 95% repellency for eight, five, six and six hours. respectively. In long-term tests with shirt piece for 16 days, product A (aerosol) and product C (aerosol) showed 100% repellency for 10 days. In the assay of quantity of DEET remained in shirt pieces with the lapse of time, two products was decreased to the same pattern.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.261-267
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• 2007

Bioassay of mosquito, Culex pipiens molestus, larva was investigated by several environment-friendly insecticides. These insecticides were Novaluron as chitin synthesis inhibitor, Metho-xyfenozide as ecdysone agonist, Pyriproxyfen as juvenile hormone mimic, and Spiromesifen as lipid biosynthesis inhibitor. The 50% lethal concentration $(LC_{50})$ of these insecticides were 0.00039, 0.07193, 0.65006 and 0.04839 ppm, respectively. Novaluron has lower concentration than any other insecticide. To determine the treatment time against larval stages, insecticides were applied to different larval stages of C. pipiens molestus. Mortality ratios of mosquito larva treated with Novaluron were 100.0, 84.5, 71.0 and 48.5% on 2, 4, 7 and 10 days after hatching from eggs, respectively. Otherwise, with the other insecticides, mortality ratios were under 80% with 2 days old larva. When exposure periods were tested to 3 or 4 days old larva against 4 insecticides, at least 3 hours were needed to 100% control effect against Novaluron, and over 12 hours with other insecticides.

• The Korean Journal of Zoology
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• v.24 no.3
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• pp.151-161
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• 1981

The field studies on the seasonal population prevalences of the vector mosquito larvae and other aquatic invertebrates were weekly carried out in the rice fields located in front of a village of Kwangtan-samri, Byeogje-myeon, Goyang-gun, Gyeonggido throughout mosquito breeding season (June-September) in 1980, and the results are as follows. The population of C. tritaeniorhynchus larvae increased soon after heavy rainfall, and decreased to some extent during the period of the insecticide application. The seasonal prevalence of A. sinensis was rather stable, not being affected by insecticide pressure at all. The population densities of other aquatic invertebrates in rice fields were seriously suppressed by the pesticide application, and their recovery was not as same as the previous level or not at all: (1) The populations of Odonata and Ephemeroptera nymphs were drastically decreased by the first application of insecticides and never recovered through out season. (2) Coleoptera seemed very susceptible to the insecticide application, as densities were markedly decreased whenever the insecticides were applied. (3) The high density of Hemiptera shown in early June were decreased sharply after the first application of pesticides, and thereasfter, some degree of recovery was shown, but suppressed by successive each application of pesticides. (4) A native species of planaria was exceptionally not influenced by the insecticide pressure, and two peaks of the density were appeared during the heavy rainfall.

• Journal of Wetlands Research
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• v.15 no.1
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• pp.19-24
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• 2013

To assess on the biological control potential with the native fishes, Aphyocypris chinensis, Oryzias sinensis, Misgurnus mizolepis, Pseudorasbora parva, Carassius auratus, Odontobutis interrupta were tested in relation to optimal condition controling mosquitoes in Seosan region. As a result of larvivorous activity for predation rate and temperature difference along kinds of native fishes, predation rate of Aphyocypris chinensis was the highest and predation rate of Misgurnus mizolepis was the lowest under the $23^{\circ}C$. Contrastively, predation rate of Aphyocypris chinensis and Odontobutis interrupta was the highest in least time. Predation rate of Misgurnus mizolepis was the lowest under the all temperature among six species fishes. Aphyocypris chinensis and Pseudorasbora parva in low, Carassius auratus, Misgurnus mizolepis and Odontobutis interrupta in bottom appeared high predation rate along the water depth. And predation rate of Oryzias sinensis was high as 95% at surface. As a result of measuring time taken to predate 50 mosquito larvae by 3 species fishes, two Aphyocypris chinensis took 10minutes, two Oryzias sinensis took 21min., two Misgurnus mizolepis took 45min. But one Aphyocypris chinensis and Misgurnus mizolepis took 8min., one Misgurnus mizolepis and Oryzias sinensis took 17min.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.381-392
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• 2018

The distribution of mosquitoes collected in the Cheongju area from 2016-2018 were compared. The collection sites were established at a residential area, migratory bird sanctuary, and cowshed using black light (BL) and BG sentinel traps. Culex pipiens was the most collected species in the residential area, and Aedes vexans was the most collected species in the migratory bird sanctuary and cowshed in all years. The BG trap collected more individuals than did the BL trap in the residential area and migratory bird sanctuary. In total, 22,679 (10 species) mosquitoes were collected in 2016, and 6,502 (8 species) and 6,803 (9 species) mosquitoes were collected in 2017 and 2018, accounting for 3.49- and 3.33-fold decreases, respectively. The relationship between meteorological conditions and mosquito density, according to various variables, was not significant different. The Chaoyang virus was found in Aedes vexans and Culex pipiens collected at the cowshed in 2016 and 2018, respectively. Based on the results of this study, it is considered that continuous surveillance of mosquitoes should be performed for controlling mosquito populations and mediating diseases spread by this vector.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.336-343
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• 2019

In order to investigate the density of seasonal incidence of mosquitoes, a vector of infectious diseases in Jeju region, this study collected mosquitoes using a Black light trap (BL) and Biogents' Sentinel 2 Mosquito Trap (BG), dividing the region into cattle sheds, habitats for migratory birds, and the downtown area, twice a month for 9 months from March through November 2018. Then, this study conducted identification and classification and checked for the presence of Flavivirus using reverse transcription polymerase chain reaction (RT-PCR). As for the mosquito population, 1,847 mosquitoes (six genera, 12 species) were collected. The places where most mosquitoes were collected were copses near craft workshops in habitats for migratory birds and Jungang-dong in the Seogwipo downtown area. For the population, Culex pipiens pallens was the dominant species (76.9%), followed by Aedes albopictus (8.9%). Most of the population was collected in June, followed by August and October. This study conducted a RT-PCR test with 1,847 collected mosquitoes, which were divided into 50 pools if they had Flavivirus. All turned out to be negative. However, the results of the investigation show the presence of Culex tritaineniorhychus, Aedes albopictus, and Anopheles sinensis and can be used as a basis for the comprehensive prevention management of mosquitoes.