Anopheles stephensi Spreads Across 10 African Countries as Resistance Defies All Current Insecticides
Updated
Updated · The New York Times · Aug 4
Anopheles stephensi Spreads Across 10 African Countries as Resistance Defies All Current Insecticides
2 articles · Updated · The New York Times · Aug 4
Summary
A new genomic analysis of specimens from 10 countries found Anopheles stephensi in Africa carries genetic resistance to every insecticide now used in mosquito-control campaigns.
That resistance helps explain why the invasive malaria-carrying mosquito has spread faster and farther than scientists feared, moving west to Ghana and south through Kenya after first appearing in Djibouti more than a decade ago.
Unlike Africa’s traditional malaria vectors, the species thrives in cities and through dry seasons, raising the risk that malaria could take hold in urban centers where it has not been a major threat.
Lagos and Kinshasa—each home to about 20 million people—are among the megacities now seen as vulnerable, and some public health experts say it is already too late to eliminate or even contain the mosquito.
With standard insecticides failing against this urban mosquito, what new strategies can save Africa's largest cities from unprecedented malaria outbreaks?
If this invasive mosquito bites during the day and resists chemicals, how can 126 million at-risk urban residents protect themselves?
126 Million at Risk: The Anopheles stephensi Invasion and the Urgent Fight Against Urban Malaria in Africa
Overview
The rapid invasion of Anopheles stephensi, an urban-adapted malaria mosquito, has transformed malaria from a rural, seasonal disease into a persistent urban crisis across Africa. After its arrival in Djibouti in 2012, the mosquito spread quickly, thriving in man-made water containers and surviving dry seasons. Its imported genetic resistance from South Asia has rendered traditional insecticide-based tools ineffective, putting an estimated 126 million additional city dwellers at risk. As malaria cases surge in urban centers, new solutions like gene drives and integrated urban planning are being developed, while funding gaps and climate change threaten to undermine progress toward elimination.