On Sept. 29, 2022, the World Health Organization announced that it had identified the spread of Anopheles stephensi as a significant threat to malaria control and elimination – particularly in Africa, where the disease hits hardest. A new WHO initiative aims to stop the further spread of this invasive mosquito species in the region.

Originally native to parts of South Asia and the Arabian Peninsula, An. stephensi has been expanding its range over the last decade, with detections reported in Djibouti (2012), Ethiopia and Sudan (2016), Somalia (2019) and Nigeria (2020). Unlike the other main mosquito vectors of malaria in Africa, it thrives in urban settings.

With more than 40% of the population in Africa living in urban environments, the invasion and spread of An. stephensi could pose a significant threat to the control and elimination of malaria in the region. But large-scale surveillance of the vector is still in its infancy, and more research and data are urgently needed.

WHO’s new initiative aims to support an effective regional response to An. stephensi on the African continent through a five-pronged approach:

• increasing collaboration across sectors and border;
• strengthening surveillance to determine the extent of the spread of An. stephensi and its role in transmission;
• improving information exchange on the presence of An. stephensi and on efforts to control it;
• developing guidance for national malaria control programmes on appropriate ways to respond to An. stephensi
• prioritizing research to evaluate the impact of interventions and tools against An. stephensi