Zika virus (ZIKV) is an ongoing global public health emergency with 74 countries (Sep. 19 2016) and territories reporting evidence of ZIKV transmission since 2015. Total 14 cases of Zika have been reported since January 2016 and all cases have been suspected as infections by mosquito bite on overseas. Vector control strategy of comprehensive national Zika control strategies will be presented on this presentation. To efficiently control Ae. albopictus when Zika inflow into ROK, nine ministers of government held on Zika countermeasure meeting, checked preparatory attitudes and assigned roles of each minster for Zika control. Korea guidelines for Ae. albopictus control were distributed to local governments and related ministers of government and vector control agents in all local government were educated by vector control experts. To block transmission of Zika virus by mosquito bite from overseas travel-associated patients Zika patients in ROK, vector monitoring and control were carried out at surroundings near residences of patients and decreased vector population density.

Vector mosquitoes are related with various diseases on human, such as malaria (Anopheles sinensis (L.), An. sinensis), Japanese encephalitis (Culex tritaeniorhynchus (L.), Cx. tritaeniorhynchus), yellow fever (Aedes albopictus (L.)), dengue hemorrhagic fever (Ae. albopictus) and filariasis (Ae. albopictus), as well as nuisance insect pests (Culex pipiens pallens Foskal, Cx. p. pallens). Continued and repeated use of conventional insecticides such as organophosphorus and carbamates, pyrethroids has often resulted in the widespread development of resistance and has undesirable effects on non-target organisms and environment. Particularly, widespread insecticide resistance has been a major obstacle in the cost-effective integrated vector management program. In theRepublic of Korea (ROK), studies on mass vector mosquito control using insecticides were mainly carried out until 1970’s such as a fuselage-mounted ULV spray system to C-46 aircraft, effectiveness of ground aerosols ULV premiumsumihtion, a helicopter application of ULV Dibrom and residual toxicity of organophosphates in animal shelters for Japanese Encephalitis (JE) and Plasmodium vivax malaria vector mosquito control. Regional insecticide resistance of vector mosquitoes has been annually evaluated since ,early 1980’s, the first detailed study on susceptibility of seven mosquito species to 13 organophosphorus insecticides revealed the DDT and lindane resistance of Cx. tritaeniorhyunchus. Marked annual and regional variations of insecticide resistance have been observed. In comparative resistance, the resistance ratios of various insecticides were compared among each other using two strains of vector mosquitoes that were collected from same locality. An. sinensis from Koyang-si in 1992 and 1981 demonstrated >100 folds and >3000 folds of higher resistance to DDT and to bio-resmethrin. An. sinensis from Paju-si in 2008 demonstrated 30 folds of higher susceptibility to fenthion than those collected in seven years ago. Cx. tritaeniorhynchus from Gwanju in 2010 and in 1992 showed >100 folds of higher resistance to pyrethroids. In comparative regional resistance monitoring, Cx. p. pallens from six localities in the ROK in 2008 and six geospatially-distant field Cx. tritaeniorhynchus strains in 2011 showed marked regional resistance variations. Field populations of Cx. tritaeniorhynchus from agricultural areas demonstrated extremely higher insecticide resistance to pyrethroids than those from non-agricultural areas. Cx. tritaeniorhynchus populations from rice paddies had been under heavy selection pressure due to pyrethroids, which were used for a long time to control agricultural pests in the localities. These results indicate that careful selection and rotational use of these insecticides may results in continued satisfactory control against field populations of vector mosquitoes

The larvicidal activities of 11 Myrtaceae essential oils and their components against Aedes aegypti were tested by the immersion method. We also tested the acute toxicity of 4 active oils and their components against the water flea, Daphnia magna. Further, the aqueous residues of these oils and their components were determined at 2 and 7 days after suspending in water. Among the 11 oils tested, 0.1 mg/mL of Melaleucalinariifolia, M. dissitiflora, M. quinquenervia, and Eucalyptus globulus oils showed strong larvicidal activity against A. aegypti. Among the test compounds, allyl isothiocyanate, γ-terpinene, p-cymene, (+)-limonene, (-)-limonene, γ-terpinene, and (E)-nerolidol showed strong larvicidal activity against A. aegypti. The acute toxicity test revealed M. linariifolia was the most toxic to D. magna. Among test compounds, allyl isothiocyanate was the most toxic to D. magna. Two days after treatment, the residues of M. dissitiflora, M. linariifolia, M. quinquenervia, and E. globulus oils in water were 55.4, 46.6, 32.4, and 14.8%, respectively. Low concentrations of allyl isothiocyanate, γ -terpinene, p-cymene, (-)-limonene, (+)-limonene, and γ-terpinene were detected in the water at 2 days after treatment. Therefore, Myrtaceae essential oils and their components could be developed as control agents against mosquito larvae.