Ecological and social determinants of Aedes aegypti and Aedes albopictus larval habitat in northeastern India
Author(s): Borah H and Bora DS
Abstract: Dengue, the arboviral threat to public health affecting millions of people globally, is transmitted by the bite of female Aedes aegypti and Aedes albopictus. The factors contributing to Ae. spp. abundance is variable, region-specific, and needs to be identified region-wise for effective vector control programs. In this study, based on dengue fever case statistics from the previous years, we selected two representatives of natural (forest and riverine) and two urbanized (Oil industrial and tea-estates) areas of upper Brahmaputra valley and dengue prone Kamrup district in the lower Brahmaputra valley of Assam for mosquito surveillance through container search. The count of both species was the highest in the urbanized regions having higher container habitats. All the entomological indices, House index, Container index, and Breteau index were higher than the WHO criteria of dengue sensitive areas from pre-monsoon to post-monsoon seasons. The temperature was the most prominent driver having a significant correlation with entomological indices with R2 values ranging from 0.825 to 0.965 in urbanized areas and 0.723 to 0.801in natural areas, followed by rainfall and humidity. Response survey of inhabitants of the study sites revealed the status of awareness and practice regarding the vector habitats. The results indicated that the combined action of urbanization, social factors, and changes in meteorological factors have primarily contributed to the large population size of dengue vectors throughout the year. Adaptive expansion of the Aedes vectors warrants the adoption of necessary precautionary measures to prevent colonization by Ae. aegypti and Ae. albopictus in urbanized areas to prevent Aedes-borne diseases, dengue, chikungunya, and zika.