Preliminary Investigation of Dengue Vectors in District Dehradun, Uttarakhand.

Preliminary investigation were carried out concerning the occurrence of dengue vectors Aedes aegypti and Aedes albopictus in rural and urban areas of various localities of Distt Dehradun. The distribution of dengue vectors, A. aegypti and A. albopictus vary from place to place. Epidemiological interpretation of various entomological indices like house index, container index, breteau index and pupal index were carried out by WHO norms. A total of 971 houses were searched during house to house larval survey for Aedes breeding in all kinds of temporary and permanent water bodies both indoors and outdoors in rural and urban areas. Of 971 houses breeding of Aedes could be detected in 226 houses, 684 water containers were searched for Aedes breeding, out of which 93 were found positive. The over all house index (HI), Container index (CI), breteau index (BI) and pupal index (PI) were 23.27%, 13.60%, 9.58% and 5.87% respectively. All the indices were found to be higher than normally acceptable limits (WHO, 2003) and Aedes breeding was recorded in all the localities except Mussorie and found to vary from locality to locality. Dengue viruses circulate mainly between human and vector mosquitoes, and the presence of vector is a limiting factor of transmission. Therefore, spatial distribution of dengue vectors is a significant concern in the epidemiology of the disease.