West Nile Virus (WNV) is transmitted by infected mosquitoes. Vector mosquitoes usually acquire these pathogens fromfeeding on an infected host, and transmit the pathogens to a naive host during feeding events. To understand the virustransmission dynamics and to survey WNV throughout country, the present study has been conducted. We collected mosquitoesat urban parks in Seongnam, Wonju, Gunsan, Daegu, and Tongyeong using CDC light trap with Dry ice from April toSeptemper in 2017 (mosquito collecting is on going). Among collected mosquitoes, blood-fed mosquitoes were conductedblood meal identification assay and the other mosquitoes were subjected to virus detection using real-time PCR method.A total of 2,290 mosquitoes representing 6 genera and 15 species were collected. The most dominant species was Culexpipiens complex (42.1%) followed by Aedes albopictus (15.1%), Ae. vexans nipponii (14.6%), Ochlerotatus koreicus (9.8%),Cx. orientalis (6.5%), and Armigeres subalbatus (4.4%). The blood meal source were of mammal (93.3%), and birds (6.7%).So far, no WNV has been detected in any mosquitoes.

West Nile Virus (WNV) is transmitted by infected mosquitoes. Vector mosquitoes usually acquire these pathogens from feeding on an infected host, and transmit the pathogens to a naive host during feeding events. To understand the virus transmission dynamics and to survey WNV throughout country, the present study has been conducted. We collected mosquitoes in Jeju, Busan, Gunsan, and Incheon using CDC light trap and BG Sentinel trap from April to October in 2016. Among collected mosquitoes, blood-fed mosquitoes were conducted blood meal identification assay and the other mosquitoes were subjected to virus detection using real-time PCR method. A total of 29,603 mosquitoes representing 8 genera and 19 species were collected. The most dominant species was Culex pippins complex (35.0%) followed by Cx. bitaeniorhynchus (12.2%), Armigeres subalbatus (11.2%), Aedes albopictus (10.8%), Ae. vexans nipponii (10.3%), and Ochlerotatus dorsalis (8.4%). The blood meal source were of mammal (70.4%), birds (29.0%) and amphibian (0.6%). WNV was not detected in any mosquitoes.

West Nile Fever is one of most serious disease spreading throughout world since 1990. West Nile Virus (WNV) is transmitted by infected mosquitoes. The possibility of overseas inflow of this virus seems to be high in Korea. To know the WNV infection of mosquitoes, we collected mosquitoes in Jeju, Busan, Gunsan, and Incheon using CDC light trap and BG Sentinel trap from April to August in 2016. Collected mosquitoes were conducted virus detection using real-time PCR method. A total of 22,632 mosquitoes representing 9 genera and 18 species were collected. The most dominant species was Culex pippins complex (36%) followed by Aedes vexans (13%), Ae. albopictus (10%) and Ochlerotatus koreicus (10%). WNV was not detected in any mosquitoes until now.

Insecticide resistance and activation of the metabolic detoxification enzymes of female Culex pipiens pallens by the blood meal were assessed using a micro-application bioassay and micro-plate enzyme activity assays. Four group of Cx. pipiens pallens were used, a susceptible non-engorging group at seven days after emerging, SNE7 Cp; a resistant non-engorging group at seven days after emerging, RNE7 Cp; a resistant engorged group at one day after blood feeding and a resistant engorged group at seven days after blood feeding, REG7 Cp. Insecticide resistance of Cx. pipiens pallans was increased by the blood feeding. Based on LC50 values, SNE7 Cp demonstrated >50 fold of higher susceptibility to all tested insecticides when compared with RNE7 Cp. RNE7 Cp showed higher susceptibility to all tested insecticides than REG1 Cp and REG7 Cp with a relative susceptibility LC50 (SRLC50) of 25.8 to 50.0 and 25.0 to 48.8. In micro-plate enzyme assays, the metabolic detoxification enzyme activity of Cx. pipiens pallans adult females was increased by the blood feeding. Activation of non-specific esterases (EST), glutathione-S-transferase (GST) and mixed function oxidase (MFO) in RNE7 were higher than in SNE7 and the all tested enzymes in REG1 and REG7 demonstrated significantly higher enzyme activation than RNE7, except for activation of GST in REG1. Activation of MFO in REG1 and REG7 were 209.4- and 74.6- fold higher than in REG7, respectively. Non-specific esterases (EST) and glutathione-S-transferase exhibited < 10 fold of higher Rr values. These results may be significant in terms of the criteria that are used to evaluate resistance, because blood fed female mosquitoes may show enhanced expression of the resistance phenotype, possibly allowing for earlier detection of insecticide resistance.