And, yes, even essential oils of Curcuma longa (turmeric) and Zingiber officinale (ginger) plant extracts ‘may also serve as a natural larvicidal agent’.
The question is: do these essential oils really effectively kill mosquitoes before they have a chance to infect you with dengue? The answer to this question is: all of these tests were done in a lab and in large enough quantities every living organism would be killed. This sort of research is hardly relevant and you could get the same effect when you drown the mosquitoes or their larvae in alcohol.
 Kumar et al: Bioefficacy of Mentha piperita essential oil against dengue fever mosquito Aedes aegypti L in Asian Pacific Journal of Tropical Biomedicine - 2011
 Giatripoulos et al: Evaluation of bioefficacy of three Citrus essential oils against the dengue vector Aedes albopictus (Diptera: Culicidae) in correlation to their components enantiomeric distribution in Parasitology Research - 2012
 Kalaivani et al: Biological activity of selected Lamiaceae and Zingiberaceae plant essential oils against the dengue vector Aedes aegypti L. (Diptera: Culicidae) in Parasitology Research - 2012