Built for the village, breached in the city: redesigning malaria vector control for Anopheles stephensi and insecticide resistance

Africa’s vector-control architecture, which has averted most of the malaria cases and deaths since 2000, was built on two assumptions: dominant vectors breed in the countryside, and pyrethroid-treated nets kill them on contact. Both are now failing at the same time. Anopheles stephensi , an efficient vector of urban malaria native to South Asia and the Arabian Peninsula, has spread across the Horn of Africa and into West Africa and is now reported in nine African countries, breeding in water containers of fast-growing cities that have never had an indigenous urban malaria vector. At the same time, pyrethroid resistance is widespread across the established African vectors, eroding the single insecticide class on which standard nets depend. This Perspective argues that vector control must be redesigned rather than merely resupplied. It reviews the evidence for next-generation nets that pair a pyrethroid with a second active ingredient; the role of piperonyl butoxide nets and spatial emanators; the larval source, house modification, and non-chemical options available in urban settings; and the surveillance demands of urban transmission. It traces the convergence of vector and parasite threats highlighted by an Ethiopian outbreak driven by A. stephensi carrying drug- and diagnosis-resistant parasites. Every element of the redesign depends on entomological and resistance surveillance, the capacity most exposed to the contraction in donor financing now underway and least well served by financing instruments built around commodity procurement. The window to redesign before failure happens is open, but it is closing fast.