Entomological Parameters and Cypermethrin Resistance of Aedes spp. in Yogyakarta City, Indonesia

Aedes is one of the genera of mosquitoes (Diptera: Culicidae) that has a role as a vector in transmitting dengue virus. The number of dengue hemorrhagic fever cases in Yogyakarta city in 2019 has significantly increased from the previous year. Yogyakarta City has been controlling the transmission of Aedes spp. using the cypermethrin insecticide in the fogging activities since four years ago. This research aims to determine the characteristics of Aedes breeding sites, their density, and the pyrethroid cypermethrin resistance status of Aedes spp. in Umbulharjo Sub-district (Giwangan, Warungboto, and Pandeyan Village). The breeding site survey was done by examining various types of containers in 100 houses. Larvae and pupae were taken from positive containers, then being reared in the laboratory. The resistance status of these Aedes adults were tested by using the CDC Bottle Bioassay Test, and biochemical resistance test to determine the monooxygenase enzyme activity. Entomological indicators such as Container Index, House Index, and Breteau Index were calculated to determine the density of Aedes spp. The characteristics of Aedes mosquito breeding sites were containers filled with clean fresh water, open, walls unscrubbed, protected from direct sunlight, no predators, indoor or outdoors, water temperature 26-28 ^° C, and pH 6 – 7.5. The density of mosquitoes was calculated using the entomological indicators which showed three village in Umbulharjo Sub-district were categorized high density of mosquitoes. The CDC Bottle Bioassay Test showed that majority of Aedes spp. were resistant to cypermethrin at 10 µg/ml in the three village of Umbulharjo Sub-district, which was supported by the involvement of monooxygenase enzyme of Aedes spp. samples. From these findings, Umbulharjo Sub-district is classified as an area with high risk of dengue fever transmission, and Aedes mosquitoes from this area were resistant to cypermethrin.