Assessment of Various Colors Combined with Insecticides in Devising Ovitraps as Attracting and Killing Tools for Mosquitoes

Abstract

Dengue virus, transmitted by Aedes aegypti mosquitoes, is the most important emerging viral disease, infecting more than 50 million people annually. Currently used sticky traps are useful tools for monitoring and controlling Ae. aegypti. Therefore, this study was conducted to evaluate the attraction of Ae. aegypti mosquitoes using various colors, materials and insecticides. The laboratory and field assessed the four different colors of ovitraps (blue, green, black and transparent). Among the tested ovitraps, the black ovitraps showed the highest number of eggs (348.8) in the laboratory and maximum eggs (80.0) in field trials. In addition, six different materials (casein, urea, yeast, fish meal, chicken meal and water) were also used to evaluate mosquito’s attraction. In our results, the highest number of eggs were collected with fish meal having 0.5% concentration in both laboratory (195.17) and the field (100.7). In laboratory trials, the Deltamethrin treated ovitraps (treated with Deltamethrin) significantly trapped and killed the highest percent of female Ae. aegypti (91.5%) compared to untreated (not-treated with Deltamethrin) ovitraps (3.3%). In field trials, the lethality was determined by installing 10 lethal ovitraps in one block and 10 untreated ovitraps in another block. The results indicate a significant reduction in eggs collected from the treated block (727 eggs) as compared to the untreated block (1865 eggs). The data also reveal that the ovitrap positive index (50) and egg density index (24.3) were also low in treated areas than in untreated areas, 83.3 and 37.3, respectively. It is concluded that the lethal ovitraps significantly reduced the Ae. aegypti population and thus could be considered an integral part of the integrated vector management (IVM) program.