Human activity has shaped the genetic diversity of dengue mosquitoes in India

From its roots in Africa, the dengue-spreading mosquito , Aedes aegypti, expanded its range in the 15th century, across the world, aided by the transatlantic slave trade between Africa, America and Europe. And by the late 19th century the insect, with its great environmental adaptability, reached India: in 2024 the country recorded around 2,50,000 dengue cases.

Today, Aedes aegypti, the main vector of chikungunya, yellow fever and Zika too, has spread to almost every environment in India: deserts, tropical forests, urban jungles, and recently, in certain rural areas where they were never found before.

Now for the first time, scientists scoured the country, sampled 126 mosquitoes from 13 regions, to better understand the evolution of this mosquito’s genetic diversity. An understanding of this heterogeneity is vital, said a paper published in Acta Tropica , as genetic diversity also influences the ability of mosquitoes in spreading disease or resisting insecticides.