Vertical dispersal of Aedes (Stegomyia) spp. in high-rise apartments in Putrajaya, Malaysia

A preliminary study on the vertical dispersal of Aedes populations in high-rise apartments was carried out in Presint 9, Putrajaya, Malaysia. Ovitraps were placed indoors within four blocks of high-rise apartments from the ground floors (0.0 - 3.0 m) until up to the tenth floors (28.1 - 30.0 m). Aedes aegypti was the dominant species found in the ovitraps (87.85%), while Aedes albopictus was found in lower numbers. From total number of larvae collected (650), 40.92% of these larvae were obtained from the fourth block; Block D. The peak density of Aedes sp. was observed at level 6 (16.1 - 18.0 m), while Ae. aegypti was found until the tenth floor (28.1 - 30.0 m). In contrast, Ae. albopictus was found only up to the sixth floor (16.1 - 18.0 m). A poor correlation of the mean number of Aedes larvae collected with the level of high-rise apartments occupied (N=40; ρ=-0.349) was also observed which indicated the possibility of lesser Aedes populations to be found at higher level of high-rise apartments. Therefore, larger scale studies are strongly recommended to examine the vertical dispersal of Aedes mosquitoes.