Urbanization Increases Aedes albopictus Larval Habitats and Accelerates Mosquito Development and Survivorship

Abstract

Introduction Aedes albopictus is a very invasive and aggressive insect vector that causes outbreaks of dengue fever, chikungunya disease, and yellow fever in many countries. Vector ecology and disease epidemiology are strongly affected by environmental changes. Urbanization is a worldwide trend and is one of the most ecologically modifying phenomena. The purpose of this study is to determine how environmental changes due to urbanization affect the ecology of Aedes albopictus.MethodsAquatic habitats and Aedes albopictus larval population surveys were conducted from May to November 2013 in three areas representing rural, suburban, and urban settings in Guangzhou, China. Ae. albopictus adults were collected monthly using BG-Sentinel traps. Ae. albopictus larva and adult life-table experiments were conducted with 20 replicates in each of the three study areas.ResultsThe urban area had the highest and the rural area had the lowest number of aquatic habitats that tested positive for Ae. albopictus larvae. Densities in the larval stages varied among the areas, but the urban area had almost two-fold higher densities in pupae and three-fold higher in adult populations compared with the suburban and rural areas. Larvae developed faster and the adult emergence rate was higher in the urban area than in suburban and rural areas. The survival time of adult mosquitoes was also longer in the urban area than it was in suburban and rural areas. Study regions, surface area, water depth, water clearance, surface type, and canopy coverage were important factors associated with the presence of Ae. albopictus larvae.ConclusionsUrbanization substantially increased the density, larval development rate, and adult survival time of Ae. albopictus, which in turn potentially increased the vector capacity, and therefore, disease transmissibility. Mosquito ecology and its correlation with dengue virus transmission should be compared in different environmental settings.

Determination of Environmental Factors Affecting Dengue Incidence in Sleman District, Yogyakarta, Indonesia

“…Vanwambeke et al (2006) also state that the presence of trees and aquatic lands is an important factor in the incidence of DHF in Thailand. Extensive settlements affect dengue cases in urban areas (Li et al, 2014), but horticulture affects dengue in sub-urban areas (Cheong et al, 2014). The presence of vegetation around the dengue patient dwellings in this study indicates that dengue in Sleman District belongs to the sub-urban type category.…”

Invasiveness ofAedes aegyptiandAedes albopictusand Vectorial Capacity for Chikungunya Virus

“…However, when A. aegypti is absent, this species can be highly productive in urban habitats [20]. A. albopictus has been regarded traditionally as a mammal-feeding generalist [19], but at many locations in its native and invasive ranges, humans account for the preponderance of blood meals identified from engorged specimens collected in nature (Table 2).…”

“…However, in south Florida before A. albopictus arrived, A. aegypti could be found in rural environments. In southern China, outside the range of A. aegypti, A. albopictus is urban dwelling [20]. Therefore, the niche width of these 2 species is not absolute.…”

Surveillance of Aedes mosquitoes in different residential types in central zone of Shah Alam, Selangor

“…Based on the epidemiological analysis, it shows that the pattern of dengue fever cases was already circulating in central zone of Shah Alam and most likely influenced by the environmental condition in relation with the ecology of Aedes mosquitoes surrounded in the study localities. The evolution of the Aedes in human habitat is significantly correlated with the environmental factors of weather variables (relative humidity, temperature, and precipitation) but the researchers ignored the environmental characteristic that serves as the fertile ground for Aedes to breed in [24,27]. Besides that, the land-use pattern in Malaysia plays a role in distribution of dengue incidence.…”