Anopheles stephensi, an invasive malaria vector, was first detected in Djibouti nearly 10 years ago and then was found in Ethiopia, Sudan, and Somalia. Informed policies and vector control decisions require understanding of the distribution, bionomics, insecticide susceptibility, and transmission potential of An. stephensi.
Abt studied these aspects as part of routine entomological monitoring in Ethiopia between 2018 and 2020. Blood-meal analysis revealed a high proportion of blood meals that were taken from goats, and only a small proportion from humans. High levels of insecticide resistance were detected to pyrethroids, carbamates, and organophosphates. Pre-exposure to piperonyl butoxide increased susceptibility to pyrethroids. Larvae were found to be susceptible to temephos.
Further work is needed to understand the role that An. stephensi will have in Plasmodium transmission and malaria case incidence in Ethiopia. While additional data are being collected, national programs can use the available data to formulate and operationalize national strategies against the threat of An. stephensi.