Indigenous and Botanically Derived Larvicides for Mosquito Vector Control in Nepal: A Review

Ramesh Bahadur Thapa; Prakriti Shrestha

Ramesh Bahadur Thapa Department of Environmental Health and Vector Biology, Gandaki Centre for Public Health Research, Pokhara, Nepal
Prakriti Shrestha Department of Pharmacognosy and Natural Products, Nepal Institute of Pharmaceutical Sciences, Bhaktapur, Nepal

Keywords: Mosquito, Nepal, Dengue, Malaria, Aedes Aegypti, Aedes Albopictus, Anopheles, Larvicide, Medicinal Plants, Botanical Insecticide, Vector Control, Integrated Vector Management

Abstract

Mosquito-borne diseases remain an important public-health challenge in Nepal, particularly because of the country's diverse ecological zones, rapid urbanisation, population movement, climatic variability and changing distribution of mosquito vectors. Dengue has emerged as a major vector-borne disease in Nepal, with Aedes aegypti and Aedes albopictus serving as important vectors. Malaria continues to require surveillance and vector-control measures, particularly in the Terai, foothills and other vulnerable ecological settings, where Anopheles fluviatilis, Anopheles annularis and Anopheles maculatus complex mosquitoes are epidemiologically relevant. Conventional chemical insecticides remain important components of vector control, but prolonged and intensive use may contribute to insecticide resistance and environmental concerns. Consequently, plant-derived products and biological larvicides have attracted increasing attention as complementary approaches to integrated vector management. The original manuscript reviewed numerous botanical extracts against mosquito larvae, including Aedes, Anopheles and Culex species. This review reframes that evidence for the Nepalese context and examines the potential application of botanically derived larvicides against mosquito vectors relevant to Nepal. Particular attention is given to plant-derived essential oils, extracts and phytochemicals, including Azadirachta indica, Zanthoxylum armatum, Cinnamomum species and other botanicals with demonstrated insecticidal or larvicidal properties. Evidence from Nepal has demonstrated mosquito-related insecticidal activity of selected Cinnamomum essential oils, while recent Nepalese research has also investigated biological larval control using native Bacillus thuringiensis. Botanical larvicides may provide an environmentally compatible complementary strategy, but their field effectiveness, standardisation, toxicity to non-target organisms, formulation stability and cost-effectiveness require further evaluation.

DOI: https://doi.org/10.24321/2349.7181.202607

How to cite this article:
Thapa R B, Shrestha P. Indigenous and Botanically Derived Larvicides for Mosquito Vector Control In Nepal: A Review. J Adv Res Med 2026; 13(3): 9-14.

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