Biting rhythm, fecundity and longevity rate ofAedes albopictus(Skuse) females from different urbanized settings in Penang Island, Malaysia under uncontrolled laboratory conditions

Abstract

27Urbanization could potentially modify Aedes albopictus' ecology by changing the 28 dynamics of the species, and increasing the abundance of their breeding sites due to 29 environmental changes, and thus contribute to dengue outbreaks. An efficient control of the 30 vector requires a deeper understanding on the biological components of this vector. Thus, this 31 study was conducted to evaluate the biting rhythm, fecundity and longevity rate of Ae. 32 albopictus in relation to urbanization strata; urban, suburban and rural areas in Penang Island, 33 Malaysia. The experiments were done in comparison to a laboratory strain. Twenty-four hours 34 biting activity of all the mosquito strains showed a clear bimodal biting activity, with morning 35 and evening twilight peaks. A two-way analysis of variance (ANOVA) found that there was 36 statistically no significant interaction (F(69,192) = 1.337, P > 0.05) between the effects of 37 biting time and mosquito strains. Meanwhile, fecundity rates were shown to be statistically 38 significantly different between mosquito strains (F(3,442) = 10.559, P < 0.05) with urban 39 areas having higher mean number of eggs (mean = 107.69, standard error = 3.98) than 40 suburban (mean = 94.48, standard error = 5.18), and rural areas (mean = 72.52, standard error 41 = 3.87). Longevity rates were significantly higher (F(3,441) = 31.259, P < 0.05) for mosquito 42 strains from urban areas compared to the other strains. These findings would provide crucial 43 and relevant fundamental information to the planning of control program in Malaysia, 44 particularly Penang.45 46 47 62 in terms of vector control. 63 64 65 Urbanization primarily results in the physical growth of urban areas, leading to 66 environmental changes. It is a global trend that results from economic development. Malaysia 67 is among the fastest growing developing countries in the East [1], and the unprecedented 68 movement of people into these areas is predicted to aggravate in the future [17]. A lot of 69 problems have arisen as a result of urbanization and Malaysia is no exception. Among the 70 problems that often take center stage in urbanization debates include environmental pollution, 71 4 space, population density and the destruction of natural ecology [20]. The socioeconomic 72 effects of urbanization have been comprehensively studied by socio-ecologists [22, 28, 15]. 73 However, the ecological effects and their impact on vector biology and vector-borne 74 infectious disease transmission remain unclear. 75 Most of the previous studies were concerned mainly on oviposition ecology from 76 larval habitats and abundance of Aedes species in various urbanized settings (13, 20, 29]. 77 However, the biting activity, fecundity and survivorship of individual female Ae. albopictus is 78 unknown in response to urbanization level particularly in Penang Island. In order to 79 determine how environmental changes due to urbanization affect the life history traits of Ae. 80 albopictus in terms of survival and reproductive fitness, thi...