Seasonal and Geographical Variation of Dengue Vectors in Narathiwat, South Thailand
Using GIS-based land use map for the urban-rural division (the relative ratio of population density adjusted to relativelyAedes-infested land area), we demonstrated significant independent observations of seasonal and geographical variation ofAedes aegyptiandAedes albopictusvectors between Muang Narathiwat district (urban setting) and neighbor districts (rural setting) of Narathiwat, Southern Thailand, based on binomial distribution ofAedesvectors in water-holding containers (water storage containers, discarded receptacles, miscellaneous containers, and natural containers). The distribution ofAedesvectors was influenced seasonally by breeding outdoors rather than indoors in all 4 containers. Accordingly, both urban and rural settings elicited significantly seasonal (wet versus dry) distributions ofAe. aegyptilarvae observed in water storage containers (P=0.001andP=0.002) and natural containers (P=0.016andP=0.015), whereas, in rural setting, the significant difference was observed in discarded receptacles (P=0.028) and miscellaneous containers (P<0.001). Seasonal distribution ofAe. albopictuslarvae in any containers in urban setting was not remarkably noticed, whereas, in rural setting, the significant difference was observed in water storage containers (P=0.007) and discarded receptacles (P<0.001). Moreover, the distributions of percentages of container index forAedes-infested households in dry season were significantly lower than that in other wet seasons,P=0.034for urban setting andP=0.001for rural setting. Findings suggest that seasonal and geographical variation ofAedesvectors affect the infestation in those containers in human inhabitations and surroundings.