A Preliminary Discussion on the Feasibility of Insecticide Application to Simultaneously Control Larvae and Adult Dengue Vectors

DOI: 10.6524/EB.202506_41(11).0001

Min-Tsung Lin^1*, Ching-Fen Ko^1,2, Jhy-Wen Wu¹

2025 Vol.41 NO.11

Correspondence Author： Min-Tsung Lin^1*

Abstract：

        With limited resources to control dengue outbreaks, some researchers have proposed that simultaneously targeting both immature and adult mosquitoes could effectively and significantly reduce mosquito populations.
In this study, we retrieved 15 relevant articles from the MEDLINE Complete and PubMed databases, focused on the simultaneous control of dengue vector larvae and adults using insecticide spraying. The findings indicate that larvicides such as Bacillus thuringiensis israelensis (Bti) or pyriproxyfen combined with adulticides like pyrethroids, using ultra-low volume machines or thermal foggers applied on space spraying, can effectively kill adult dengue vectors while also causing larval mortality or inhibiting adult emergence. This approach delays the recovery of adult mosquito populations to pre-spraying levels, demonstrating the feasibility of using insecticide spraying for the simultaneous control of both larvae and adult dengue vectors.
        Although resistance to these two larvicides is rare, and their combination with adulticides has not been shown to reduce efficacy against adult mosquitoes, the issue of insecticide resistance in adult dengue vectors remains a significant concern. Therefore, the selection of adulticides is essential to effectively kill adult mosquitoes and delay the development of resistance.
        In Taiwan, Bti and pyriproxyfen products are not registered for use in combination with adulticides or for space spraying. Therefore, whether this spraying method, as practiced abroad, can be adopted locally remains a subject of debate. It is recommended that insecticide manufacturers conduct a thorough evaluation of the feasibility of this vector control technique and collaborate with regulatory authorities overseeing environmental pesticides to update application guidelines. This would enable health and environmental agencies to adopt this vector control strategy under appropriate conditions to effectively eliminate dengue vectors.