Aedes aegypti: Aedes aegypti colony was maintained at insectary (54 cm × 45 cm × 40 cm) at 27˚C ± 2˚C and 80% ± 2% Relative humidity with a photoperiod of 12:10 hours light and dark cycles. The egg strips were obtained from Vector Control Research Center (VCRC), Puducherry to start the colony. The strips were immersed in dechlorinated tap water for hatching. To obtain the larvae of equal developmental stage, eggs were introduced by adding a stimulant such as ascorbic acid (100 mg/L) to water [18]. This started the eclosion process. The emerged larvae were maintained in Petri dishes (10.5 cm diameter) with dechlorinated tap water. Larvae were fed with a diet of yeast and dog biscuits in the ratio of 3:1. The first instar larvae developed into pupae in about 7 - 10 days through four stages. The pupae were separated by using a glass dropper into glass Petri dishes and were kept in mosquito net cages (40 cm × 45 cm × 40 cm) for emergence. The newly emerged mosquitoes were provided with 5% glucose solution soaked in cotton wool, which was placed inside the mosquito net cage for nourishment [19]. After three days of emergence, adults were given a blood meal of pigeon [20]. Glass Petri dishes of 50 mL of tap water lined with filter paper were kept inside the cage for oviposition. The eggs thus obtained were immersed in larval trays containing dechlorinated tap water for hatching.